What is Neuropsychology

Study of brainndashbehavior relations (sometimesreferred to as functional localization)

Functional Lateralization ndash refers to notion thata function may depend on one side(hemisphere) of the brain

Definition of Clinical Neuropsychologist A clinical neuropsychologist is a professional

psychologist who applies principles of assessment and intervention based upon the scientific study of human behavior as it relates to normal and abnormal functioning of the central nervous system The clinical neuropsychologist is a doctoral-level psychology provider of diagnostic and intervention services who has demonstrated competence in the application of such principles for human welfare following

A doctoral degree in psychology from an accredited university training program

An internship or its equivalent in a clinically relevant area of professional psychology

The equivalent of two (fulltime) years of experience and specialized training at least one of which is at the post-doctoral level in the study and practice of clinical neuropsychology and related neurosciences These two years include supervision by a clinical neuropsychologist

A license in his or her state or province to practice psychology andor clinical neuropsychology independently or is employed as a neuropsychologist by an exempt agency

Different types ofNeuropsychologists Subareas

1048698 Experimental neuropsychologists ndash work to understandthe neural bases of cognition by doing studiesndash Experimental neuropsychology = cognitive neuropsychology or cognitive neuroscience

1048698 Clinical neuropsychologists ndash work in health-relatedsettings (eg hospitals clinics) with patientsndash Involved in diagnosisndash Involved in rehabilitation (eg designing programs)ndash May be involved in researchndash Clinical neuropsychology

How do we study brain-behaviorrelations (Techniques)

Invasivendash Lesionndash Inject radioactive tracer

Non-invasivendash Brain-imaging to see what regions are active during specific mental taskndash Record activity of cells to determine what activity makes them respondndash Present information to different hemispheres and see which side does task better or faster

Why study brain-behaviorrelations

1048698 Diagnostic purposes1048698 Rehabilitation purposes1048698 Intellectual curiosity

Methods inNeuropsychology

Method of converging operations

Use a number of different methods andpopulations1048698 Evidence obtained from a set ofexperiments converge on the sameconclusionndash eg fMRI and lesion studies

Research considerations

1048698 What type of participants1048698 How will we gather information about their brains1048698 How will be measure behavior

Research Participants

1048698 (1) Patients with lesions1048698 (2) Healthy Individuals1048698 (3) Animals

(1) Patients with lesions

1048698 Question What functions supported by thisneural site

1048698 Studies need to include patients with lesionsto a specific site and patients with lesions to adifferent site

1048698 lsquoDouble dissociationrsquo - lesions have converseeffects on two distinct cognitive functions

1048698 Allow one to conclude that structuresfunctions are independent

1048698 Question What neural sites areassociated with a particular deficit

ndash eg Memory impairment associated withdamage to

ndash Brenda Milnerrsquos work with temporal lobe epilepsy and memory where hippocampus was found to be important for learning

Problems with lesion method

1048698 Brain damage messy in humans

(1) People vary in their genetic andenvironmental characteristicsbull eg differ in education onset of dementiandash Lesions vary in their extent and originbull Stroke vs tumor vs bullet

(2) Lesion does not allow us to observe directly the function served by the lesioned site

1048698 Only know how brain performs withoutthat particular area

1048698 We can infer the site may be critical but we can not identify all the areas that may be involved

1048698 Site may not be critical in performing a particular function rather may contain axons that connect regions that

must interact for correct performance

ndash Disconnection syndromebull Split brainbull Conduction aphasia

Associated problemsingle cases or groups

1048698 Groups of patients may be so hetergeneous in their behavior that lsquogroup averagersquo is meaningless

ndash Argues for single case approach

1048698 Problem with single case approachndash Is pattern observed representative of people in

generalndash Does not allow one to rule out random error

1048698 Use multiple case approach validating research findings on a series of patients or

1048698 Follow-up findings from single-case withgroup studies

(2) Neurologically intactIndividuals

1048698 These persons provide the control group that allows us to determine thedegree to which performance of brain damaged people is compromised

1048698 Well-designed studies must include appropriate control group

(3) Animal Populations

1048698 Allows for control over ndash Environmental conditionsexperience ndash Size and nature of lesions ndash Genetic differences etc

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

Definition of Clinical Neuropsychologist A clinical neuropsychologist is a professional

psychologist who applies principles of assessment and intervention based upon the scientific study of human behavior as it relates to normal and abnormal functioning of the central nervous system The clinical neuropsychologist is a doctoral-level psychology provider of diagnostic and intervention services who has demonstrated competence in the application of such principles for human welfare following

A doctoral degree in psychology from an accredited university training program

An internship or its equivalent in a clinically relevant area of professional psychology

The equivalent of two (fulltime) years of experience and specialized training at least one of which is at the post-doctoral level in the study and practice of clinical neuropsychology and related neurosciences These two years include supervision by a clinical neuropsychologist

A license in his or her state or province to practice psychology andor clinical neuropsychology independently or is employed as a neuropsychologist by an exempt agency

Different types ofNeuropsychologists Subareas

1048698 Experimental neuropsychologists ndash work to understandthe neural bases of cognition by doing studiesndash Experimental neuropsychology = cognitive neuropsychology or cognitive neuroscience

1048698 Clinical neuropsychologists ndash work in health-relatedsettings (eg hospitals clinics) with patientsndash Involved in diagnosisndash Involved in rehabilitation (eg designing programs)ndash May be involved in researchndash Clinical neuropsychology

How do we study brain-behaviorrelations (Techniques)

Invasivendash Lesionndash Inject radioactive tracer

Non-invasivendash Brain-imaging to see what regions are active during specific mental taskndash Record activity of cells to determine what activity makes them respondndash Present information to different hemispheres and see which side does task better or faster

Why study brain-behaviorrelations

1048698 Diagnostic purposes1048698 Rehabilitation purposes1048698 Intellectual curiosity

Methods inNeuropsychology

Method of converging operations

Use a number of different methods andpopulations1048698 Evidence obtained from a set ofexperiments converge on the sameconclusionndash eg fMRI and lesion studies

Research considerations

1048698 What type of participants1048698 How will we gather information about their brains1048698 How will be measure behavior

Research Participants

1048698 (1) Patients with lesions1048698 (2) Healthy Individuals1048698 (3) Animals

(1) Patients with lesions

1048698 Question What functions supported by thisneural site

1048698 Studies need to include patients with lesionsto a specific site and patients with lesions to adifferent site

1048698 lsquoDouble dissociationrsquo - lesions have converseeffects on two distinct cognitive functions

1048698 Allow one to conclude that structuresfunctions are independent

1048698 Question What neural sites areassociated with a particular deficit

ndash eg Memory impairment associated withdamage to

ndash Brenda Milnerrsquos work with temporal lobe epilepsy and memory where hippocampus was found to be important for learning

Problems with lesion method

1048698 Brain damage messy in humans

(1) People vary in their genetic andenvironmental characteristicsbull eg differ in education onset of dementiandash Lesions vary in their extent and originbull Stroke vs tumor vs bullet

(2) Lesion does not allow us to observe directly the function served by the lesioned site

1048698 Only know how brain performs withoutthat particular area

1048698 We can infer the site may be critical but we can not identify all the areas that may be involved

1048698 Site may not be critical in performing a particular function rather may contain axons that connect regions that

must interact for correct performance

ndash Disconnection syndromebull Split brainbull Conduction aphasia

Associated problemsingle cases or groups

1048698 Groups of patients may be so hetergeneous in their behavior that lsquogroup averagersquo is meaningless

ndash Argues for single case approach

1048698 Problem with single case approachndash Is pattern observed representative of people in

generalndash Does not allow one to rule out random error

1048698 Use multiple case approach validating research findings on a series of patients or

1048698 Follow-up findings from single-case withgroup studies

(2) Neurologically intactIndividuals

1048698 These persons provide the control group that allows us to determine thedegree to which performance of brain damaged people is compromised

1048698 Well-designed studies must include appropriate control group

(3) Animal Populations

1048698 Allows for control over ndash Environmental conditionsexperience ndash Size and nature of lesions ndash Genetic differences etc

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

A doctoral degree in psychology from an accredited university training program

An internship or its equivalent in a clinically relevant area of professional psychology

The equivalent of two (fulltime) years of experience and specialized training at least one of which is at the post-doctoral level in the study and practice of clinical neuropsychology and related neurosciences These two years include supervision by a clinical neuropsychologist

A license in his or her state or province to practice psychology andor clinical neuropsychology independently or is employed as a neuropsychologist by an exempt agency

Different types ofNeuropsychologists Subareas

1048698 Experimental neuropsychologists ndash work to understandthe neural bases of cognition by doing studiesndash Experimental neuropsychology = cognitive neuropsychology or cognitive neuroscience

1048698 Clinical neuropsychologists ndash work in health-relatedsettings (eg hospitals clinics) with patientsndash Involved in diagnosisndash Involved in rehabilitation (eg designing programs)ndash May be involved in researchndash Clinical neuropsychology

How do we study brain-behaviorrelations (Techniques)

Invasivendash Lesionndash Inject radioactive tracer

Non-invasivendash Brain-imaging to see what regions are active during specific mental taskndash Record activity of cells to determine what activity makes them respondndash Present information to different hemispheres and see which side does task better or faster

Why study brain-behaviorrelations

1048698 Diagnostic purposes1048698 Rehabilitation purposes1048698 Intellectual curiosity

Methods inNeuropsychology

Method of converging operations

Use a number of different methods andpopulations1048698 Evidence obtained from a set ofexperiments converge on the sameconclusionndash eg fMRI and lesion studies

Research considerations

1048698 What type of participants1048698 How will we gather information about their brains1048698 How will be measure behavior

Research Participants

1048698 (1) Patients with lesions1048698 (2) Healthy Individuals1048698 (3) Animals

(1) Patients with lesions

1048698 Question What functions supported by thisneural site

1048698 Studies need to include patients with lesionsto a specific site and patients with lesions to adifferent site

1048698 lsquoDouble dissociationrsquo - lesions have converseeffects on two distinct cognitive functions

1048698 Allow one to conclude that structuresfunctions are independent

1048698 Question What neural sites areassociated with a particular deficit

ndash eg Memory impairment associated withdamage to

ndash Brenda Milnerrsquos work with temporal lobe epilepsy and memory where hippocampus was found to be important for learning

Problems with lesion method

1048698 Brain damage messy in humans

(1) People vary in their genetic andenvironmental characteristicsbull eg differ in education onset of dementiandash Lesions vary in their extent and originbull Stroke vs tumor vs bullet

(2) Lesion does not allow us to observe directly the function served by the lesioned site

1048698 Only know how brain performs withoutthat particular area

1048698 We can infer the site may be critical but we can not identify all the areas that may be involved

1048698 Site may not be critical in performing a particular function rather may contain axons that connect regions that

must interact for correct performance

ndash Disconnection syndromebull Split brainbull Conduction aphasia

Associated problemsingle cases or groups

1048698 Groups of patients may be so hetergeneous in their behavior that lsquogroup averagersquo is meaningless

ndash Argues for single case approach

1048698 Problem with single case approachndash Is pattern observed representative of people in

generalndash Does not allow one to rule out random error

1048698 Use multiple case approach validating research findings on a series of patients or

1048698 Follow-up findings from single-case withgroup studies

(2) Neurologically intactIndividuals

1048698 These persons provide the control group that allows us to determine thedegree to which performance of brain damaged people is compromised

1048698 Well-designed studies must include appropriate control group

(3) Animal Populations

1048698 Allows for control over ndash Environmental conditionsexperience ndash Size and nature of lesions ndash Genetic differences etc

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

Different types ofNeuropsychologists Subareas

1048698 Experimental neuropsychologists ndash work to understandthe neural bases of cognition by doing studiesndash Experimental neuropsychology = cognitive neuropsychology or cognitive neuroscience

1048698 Clinical neuropsychologists ndash work in health-relatedsettings (eg hospitals clinics) with patientsndash Involved in diagnosisndash Involved in rehabilitation (eg designing programs)ndash May be involved in researchndash Clinical neuropsychology

How do we study brain-behaviorrelations (Techniques)

Invasivendash Lesionndash Inject radioactive tracer

Non-invasivendash Brain-imaging to see what regions are active during specific mental taskndash Record activity of cells to determine what activity makes them respondndash Present information to different hemispheres and see which side does task better or faster

Why study brain-behaviorrelations

1048698 Diagnostic purposes1048698 Rehabilitation purposes1048698 Intellectual curiosity

Methods inNeuropsychology

Method of converging operations

Use a number of different methods andpopulations1048698 Evidence obtained from a set ofexperiments converge on the sameconclusionndash eg fMRI and lesion studies

Research considerations

1048698 What type of participants1048698 How will we gather information about their brains1048698 How will be measure behavior

Research Participants

1048698 (1) Patients with lesions1048698 (2) Healthy Individuals1048698 (3) Animals

(1) Patients with lesions

1048698 Question What functions supported by thisneural site

1048698 Studies need to include patients with lesionsto a specific site and patients with lesions to adifferent site

1048698 lsquoDouble dissociationrsquo - lesions have converseeffects on two distinct cognitive functions

1048698 Allow one to conclude that structuresfunctions are independent

1048698 Question What neural sites areassociated with a particular deficit

ndash eg Memory impairment associated withdamage to

ndash Brenda Milnerrsquos work with temporal lobe epilepsy and memory where hippocampus was found to be important for learning

Problems with lesion method

1048698 Brain damage messy in humans

(1) People vary in their genetic andenvironmental characteristicsbull eg differ in education onset of dementiandash Lesions vary in their extent and originbull Stroke vs tumor vs bullet

(2) Lesion does not allow us to observe directly the function served by the lesioned site

1048698 Only know how brain performs withoutthat particular area

1048698 We can infer the site may be critical but we can not identify all the areas that may be involved

1048698 Site may not be critical in performing a particular function rather may contain axons that connect regions that

must interact for correct performance

ndash Disconnection syndromebull Split brainbull Conduction aphasia

Associated problemsingle cases or groups

1048698 Groups of patients may be so hetergeneous in their behavior that lsquogroup averagersquo is meaningless

ndash Argues for single case approach

1048698 Problem with single case approachndash Is pattern observed representative of people in

generalndash Does not allow one to rule out random error

1048698 Use multiple case approach validating research findings on a series of patients or

1048698 Follow-up findings from single-case withgroup studies

(2) Neurologically intactIndividuals

1048698 These persons provide the control group that allows us to determine thedegree to which performance of brain damaged people is compromised

1048698 Well-designed studies must include appropriate control group

(3) Animal Populations

1048698 Allows for control over ndash Environmental conditionsexperience ndash Size and nature of lesions ndash Genetic differences etc

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

How do we study brain-behaviorrelations (Techniques)

Invasivendash Lesionndash Inject radioactive tracer

Non-invasivendash Brain-imaging to see what regions are active during specific mental taskndash Record activity of cells to determine what activity makes them respondndash Present information to different hemispheres and see which side does task better or faster

Why study brain-behaviorrelations

1048698 Diagnostic purposes1048698 Rehabilitation purposes1048698 Intellectual curiosity

Methods inNeuropsychology

Method of converging operations

Use a number of different methods andpopulations1048698 Evidence obtained from a set ofexperiments converge on the sameconclusionndash eg fMRI and lesion studies

Research considerations

1048698 What type of participants1048698 How will we gather information about their brains1048698 How will be measure behavior

Research Participants

1048698 (1) Patients with lesions1048698 (2) Healthy Individuals1048698 (3) Animals

(1) Patients with lesions

1048698 Question What functions supported by thisneural site

1048698 Studies need to include patients with lesionsto a specific site and patients with lesions to adifferent site

1048698 lsquoDouble dissociationrsquo - lesions have converseeffects on two distinct cognitive functions

1048698 Allow one to conclude that structuresfunctions are independent

1048698 Question What neural sites areassociated with a particular deficit

ndash eg Memory impairment associated withdamage to

ndash Brenda Milnerrsquos work with temporal lobe epilepsy and memory where hippocampus was found to be important for learning

Problems with lesion method

1048698 Brain damage messy in humans

(1) People vary in their genetic andenvironmental characteristicsbull eg differ in education onset of dementiandash Lesions vary in their extent and originbull Stroke vs tumor vs bullet

(2) Lesion does not allow us to observe directly the function served by the lesioned site

1048698 Only know how brain performs withoutthat particular area

1048698 We can infer the site may be critical but we can not identify all the areas that may be involved

1048698 Site may not be critical in performing a particular function rather may contain axons that connect regions that

must interact for correct performance

ndash Disconnection syndromebull Split brainbull Conduction aphasia

Associated problemsingle cases or groups

1048698 Groups of patients may be so hetergeneous in their behavior that lsquogroup averagersquo is meaningless

ndash Argues for single case approach

1048698 Problem with single case approachndash Is pattern observed representative of people in

generalndash Does not allow one to rule out random error

1048698 Use multiple case approach validating research findings on a series of patients or

1048698 Follow-up findings from single-case withgroup studies

(2) Neurologically intactIndividuals

1048698 These persons provide the control group that allows us to determine thedegree to which performance of brain damaged people is compromised

1048698 Well-designed studies must include appropriate control group

(3) Animal Populations

1048698 Allows for control over ndash Environmental conditionsexperience ndash Size and nature of lesions ndash Genetic differences etc

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

Why study brain-behaviorrelations

1048698 Diagnostic purposes1048698 Rehabilitation purposes1048698 Intellectual curiosity

Methods inNeuropsychology

Method of converging operations

Use a number of different methods andpopulations1048698 Evidence obtained from a set ofexperiments converge on the sameconclusionndash eg fMRI and lesion studies

Research considerations

1048698 What type of participants1048698 How will we gather information about their brains1048698 How will be measure behavior

Research Participants

1048698 (1) Patients with lesions1048698 (2) Healthy Individuals1048698 (3) Animals

(1) Patients with lesions

1048698 Question What functions supported by thisneural site

1048698 Studies need to include patients with lesionsto a specific site and patients with lesions to adifferent site

1048698 lsquoDouble dissociationrsquo - lesions have converseeffects on two distinct cognitive functions

1048698 Allow one to conclude that structuresfunctions are independent

1048698 Question What neural sites areassociated with a particular deficit

ndash eg Memory impairment associated withdamage to

ndash Brenda Milnerrsquos work with temporal lobe epilepsy and memory where hippocampus was found to be important for learning

Problems with lesion method

1048698 Brain damage messy in humans

(1) People vary in their genetic andenvironmental characteristicsbull eg differ in education onset of dementiandash Lesions vary in their extent and originbull Stroke vs tumor vs bullet

(2) Lesion does not allow us to observe directly the function served by the lesioned site

1048698 Only know how brain performs withoutthat particular area

1048698 We can infer the site may be critical but we can not identify all the areas that may be involved

1048698 Site may not be critical in performing a particular function rather may contain axons that connect regions that

must interact for correct performance

ndash Disconnection syndromebull Split brainbull Conduction aphasia

Associated problemsingle cases or groups

1048698 Groups of patients may be so hetergeneous in their behavior that lsquogroup averagersquo is meaningless

ndash Argues for single case approach

1048698 Problem with single case approachndash Is pattern observed representative of people in

generalndash Does not allow one to rule out random error

1048698 Use multiple case approach validating research findings on a series of patients or

1048698 Follow-up findings from single-case withgroup studies

(2) Neurologically intactIndividuals

1048698 These persons provide the control group that allows us to determine thedegree to which performance of brain damaged people is compromised

1048698 Well-designed studies must include appropriate control group

(3) Animal Populations

1048698 Allows for control over ndash Environmental conditionsexperience ndash Size and nature of lesions ndash Genetic differences etc

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

Methods inNeuropsychology

Method of converging operations

Use a number of different methods andpopulations1048698 Evidence obtained from a set ofexperiments converge on the sameconclusionndash eg fMRI and lesion studies

Research considerations

1048698 What type of participants1048698 How will we gather information about their brains1048698 How will be measure behavior

Research Participants

1048698 (1) Patients with lesions1048698 (2) Healthy Individuals1048698 (3) Animals

(1) Patients with lesions

1048698 Question What functions supported by thisneural site

1048698 Studies need to include patients with lesionsto a specific site and patients with lesions to adifferent site

1048698 lsquoDouble dissociationrsquo - lesions have converseeffects on two distinct cognitive functions

1048698 Allow one to conclude that structuresfunctions are independent

1048698 Question What neural sites areassociated with a particular deficit

ndash eg Memory impairment associated withdamage to

ndash Brenda Milnerrsquos work with temporal lobe epilepsy and memory where hippocampus was found to be important for learning

Problems with lesion method

1048698 Brain damage messy in humans

(1) People vary in their genetic andenvironmental characteristicsbull eg differ in education onset of dementiandash Lesions vary in their extent and originbull Stroke vs tumor vs bullet

(2) Lesion does not allow us to observe directly the function served by the lesioned site

1048698 Only know how brain performs withoutthat particular area

1048698 We can infer the site may be critical but we can not identify all the areas that may be involved

1048698 Site may not be critical in performing a particular function rather may contain axons that connect regions that

must interact for correct performance

ndash Disconnection syndromebull Split brainbull Conduction aphasia

Associated problemsingle cases or groups

1048698 Groups of patients may be so hetergeneous in their behavior that lsquogroup averagersquo is meaningless

ndash Argues for single case approach

1048698 Problem with single case approachndash Is pattern observed representative of people in

generalndash Does not allow one to rule out random error

1048698 Use multiple case approach validating research findings on a series of patients or

1048698 Follow-up findings from single-case withgroup studies

(2) Neurologically intactIndividuals

1048698 These persons provide the control group that allows us to determine thedegree to which performance of brain damaged people is compromised

1048698 Well-designed studies must include appropriate control group

(3) Animal Populations

1048698 Allows for control over ndash Environmental conditionsexperience ndash Size and nature of lesions ndash Genetic differences etc

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

Method of converging operations

Use a number of different methods andpopulations1048698 Evidence obtained from a set ofexperiments converge on the sameconclusionndash eg fMRI and lesion studies

Research considerations

1048698 What type of participants1048698 How will we gather information about their brains1048698 How will be measure behavior

Research Participants

1048698 (1) Patients with lesions1048698 (2) Healthy Individuals1048698 (3) Animals

(1) Patients with lesions

1048698 Question What functions supported by thisneural site

1048698 Studies need to include patients with lesionsto a specific site and patients with lesions to adifferent site

1048698 lsquoDouble dissociationrsquo - lesions have converseeffects on two distinct cognitive functions

1048698 Allow one to conclude that structuresfunctions are independent

1048698 Question What neural sites areassociated with a particular deficit

ndash eg Memory impairment associated withdamage to

ndash Brenda Milnerrsquos work with temporal lobe epilepsy and memory where hippocampus was found to be important for learning

Problems with lesion method

1048698 Brain damage messy in humans

(1) People vary in their genetic andenvironmental characteristicsbull eg differ in education onset of dementiandash Lesions vary in their extent and originbull Stroke vs tumor vs bullet

(2) Lesion does not allow us to observe directly the function served by the lesioned site

1048698 Only know how brain performs withoutthat particular area

1048698 We can infer the site may be critical but we can not identify all the areas that may be involved

1048698 Site may not be critical in performing a particular function rather may contain axons that connect regions that

must interact for correct performance

ndash Disconnection syndromebull Split brainbull Conduction aphasia

Associated problemsingle cases or groups

1048698 Groups of patients may be so hetergeneous in their behavior that lsquogroup averagersquo is meaningless

ndash Argues for single case approach

1048698 Problem with single case approachndash Is pattern observed representative of people in

generalndash Does not allow one to rule out random error

1048698 Use multiple case approach validating research findings on a series of patients or

1048698 Follow-up findings from single-case withgroup studies

(2) Neurologically intactIndividuals

1048698 These persons provide the control group that allows us to determine thedegree to which performance of brain damaged people is compromised

1048698 Well-designed studies must include appropriate control group

(3) Animal Populations

1048698 Allows for control over ndash Environmental conditionsexperience ndash Size and nature of lesions ndash Genetic differences etc

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

Research considerations

1048698 What type of participants1048698 How will we gather information about their brains1048698 How will be measure behavior

Research Participants

1048698 (1) Patients with lesions1048698 (2) Healthy Individuals1048698 (3) Animals

(1) Patients with lesions

1048698 Question What functions supported by thisneural site

1048698 Studies need to include patients with lesionsto a specific site and patients with lesions to adifferent site

1048698 lsquoDouble dissociationrsquo - lesions have converseeffects on two distinct cognitive functions

1048698 Allow one to conclude that structuresfunctions are independent

1048698 Question What neural sites areassociated with a particular deficit

ndash eg Memory impairment associated withdamage to

ndash Brenda Milnerrsquos work with temporal lobe epilepsy and memory where hippocampus was found to be important for learning

Problems with lesion method

1048698 Brain damage messy in humans

(1) People vary in their genetic andenvironmental characteristicsbull eg differ in education onset of dementiandash Lesions vary in their extent and originbull Stroke vs tumor vs bullet

(2) Lesion does not allow us to observe directly the function served by the lesioned site

1048698 Only know how brain performs withoutthat particular area

1048698 We can infer the site may be critical but we can not identify all the areas that may be involved

1048698 Site may not be critical in performing a particular function rather may contain axons that connect regions that

must interact for correct performance

ndash Disconnection syndromebull Split brainbull Conduction aphasia

Associated problemsingle cases or groups

1048698 Groups of patients may be so hetergeneous in their behavior that lsquogroup averagersquo is meaningless

ndash Argues for single case approach

1048698 Problem with single case approachndash Is pattern observed representative of people in

generalndash Does not allow one to rule out random error

1048698 Use multiple case approach validating research findings on a series of patients or

1048698 Follow-up findings from single-case withgroup studies

(2) Neurologically intactIndividuals

1048698 These persons provide the control group that allows us to determine thedegree to which performance of brain damaged people is compromised

1048698 Well-designed studies must include appropriate control group

(3) Animal Populations

1048698 Allows for control over ndash Environmental conditionsexperience ndash Size and nature of lesions ndash Genetic differences etc

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

Research Participants

1048698 (1) Patients with lesions1048698 (2) Healthy Individuals1048698 (3) Animals

(1) Patients with lesions

1048698 Question What functions supported by thisneural site

1048698 Studies need to include patients with lesionsto a specific site and patients with lesions to adifferent site

1048698 lsquoDouble dissociationrsquo - lesions have converseeffects on two distinct cognitive functions

1048698 Allow one to conclude that structuresfunctions are independent

1048698 Question What neural sites areassociated with a particular deficit

ndash eg Memory impairment associated withdamage to

ndash Brenda Milnerrsquos work with temporal lobe epilepsy and memory where hippocampus was found to be important for learning

Problems with lesion method

1048698 Brain damage messy in humans

(1) People vary in their genetic andenvironmental characteristicsbull eg differ in education onset of dementiandash Lesions vary in their extent and originbull Stroke vs tumor vs bullet

(2) Lesion does not allow us to observe directly the function served by the lesioned site

1048698 Only know how brain performs withoutthat particular area

1048698 We can infer the site may be critical but we can not identify all the areas that may be involved

1048698 Site may not be critical in performing a particular function rather may contain axons that connect regions that

must interact for correct performance

ndash Disconnection syndromebull Split brainbull Conduction aphasia

Associated problemsingle cases or groups

1048698 Groups of patients may be so hetergeneous in their behavior that lsquogroup averagersquo is meaningless

ndash Argues for single case approach

1048698 Problem with single case approachndash Is pattern observed representative of people in

generalndash Does not allow one to rule out random error

1048698 Use multiple case approach validating research findings on a series of patients or

1048698 Follow-up findings from single-case withgroup studies

(2) Neurologically intactIndividuals

1048698 These persons provide the control group that allows us to determine thedegree to which performance of brain damaged people is compromised

1048698 Well-designed studies must include appropriate control group

(3) Animal Populations

1048698 Allows for control over ndash Environmental conditionsexperience ndash Size and nature of lesions ndash Genetic differences etc

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

(1) Patients with lesions

1048698 Question What functions supported by thisneural site

1048698 Studies need to include patients with lesionsto a specific site and patients with lesions to adifferent site

1048698 lsquoDouble dissociationrsquo - lesions have converseeffects on two distinct cognitive functions

1048698 Allow one to conclude that structuresfunctions are independent

1048698 Question What neural sites areassociated with a particular deficit

ndash eg Memory impairment associated withdamage to

ndash Brenda Milnerrsquos work with temporal lobe epilepsy and memory where hippocampus was found to be important for learning

Problems with lesion method

1048698 Brain damage messy in humans

(1) People vary in their genetic andenvironmental characteristicsbull eg differ in education onset of dementiandash Lesions vary in their extent and originbull Stroke vs tumor vs bullet

(2) Lesion does not allow us to observe directly the function served by the lesioned site

1048698 Only know how brain performs withoutthat particular area

1048698 We can infer the site may be critical but we can not identify all the areas that may be involved

1048698 Site may not be critical in performing a particular function rather may contain axons that connect regions that

must interact for correct performance

ndash Disconnection syndromebull Split brainbull Conduction aphasia

Associated problemsingle cases or groups

1048698 Groups of patients may be so hetergeneous in their behavior that lsquogroup averagersquo is meaningless

ndash Argues for single case approach

1048698 Problem with single case approachndash Is pattern observed representative of people in

generalndash Does not allow one to rule out random error

1048698 Use multiple case approach validating research findings on a series of patients or

1048698 Follow-up findings from single-case withgroup studies

(2) Neurologically intactIndividuals

1048698 These persons provide the control group that allows us to determine thedegree to which performance of brain damaged people is compromised

1048698 Well-designed studies must include appropriate control group

(3) Animal Populations

1048698 Allows for control over ndash Environmental conditionsexperience ndash Size and nature of lesions ndash Genetic differences etc

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

1048698 Question What neural sites areassociated with a particular deficit

ndash eg Memory impairment associated withdamage to

ndash Brenda Milnerrsquos work with temporal lobe epilepsy and memory where hippocampus was found to be important for learning

Problems with lesion method

1048698 Brain damage messy in humans

(1) People vary in their genetic andenvironmental characteristicsbull eg differ in education onset of dementiandash Lesions vary in their extent and originbull Stroke vs tumor vs bullet

(2) Lesion does not allow us to observe directly the function served by the lesioned site

1048698 Only know how brain performs withoutthat particular area

1048698 We can infer the site may be critical but we can not identify all the areas that may be involved

1048698 Site may not be critical in performing a particular function rather may contain axons that connect regions that

must interact for correct performance

ndash Disconnection syndromebull Split brainbull Conduction aphasia

Associated problemsingle cases or groups

1048698 Groups of patients may be so hetergeneous in their behavior that lsquogroup averagersquo is meaningless

ndash Argues for single case approach

1048698 Problem with single case approachndash Is pattern observed representative of people in

generalndash Does not allow one to rule out random error

1048698 Use multiple case approach validating research findings on a series of patients or

1048698 Follow-up findings from single-case withgroup studies

(2) Neurologically intactIndividuals

1048698 These persons provide the control group that allows us to determine thedegree to which performance of brain damaged people is compromised

1048698 Well-designed studies must include appropriate control group

(3) Animal Populations

1048698 Allows for control over ndash Environmental conditionsexperience ndash Size and nature of lesions ndash Genetic differences etc

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

Problems with lesion method

1048698 Brain damage messy in humans

(1) People vary in their genetic andenvironmental characteristicsbull eg differ in education onset of dementiandash Lesions vary in their extent and originbull Stroke vs tumor vs bullet

(2) Lesion does not allow us to observe directly the function served by the lesioned site

1048698 Only know how brain performs withoutthat particular area

1048698 We can infer the site may be critical but we can not identify all the areas that may be involved

1048698 Site may not be critical in performing a particular function rather may contain axons that connect regions that

must interact for correct performance

ndash Disconnection syndromebull Split brainbull Conduction aphasia

Associated problemsingle cases or groups

1048698 Groups of patients may be so hetergeneous in their behavior that lsquogroup averagersquo is meaningless

ndash Argues for single case approach

1048698 Problem with single case approachndash Is pattern observed representative of people in

generalndash Does not allow one to rule out random error

1048698 Use multiple case approach validating research findings on a series of patients or

1048698 Follow-up findings from single-case withgroup studies

(2) Neurologically intactIndividuals

1048698 These persons provide the control group that allows us to determine thedegree to which performance of brain damaged people is compromised

1048698 Well-designed studies must include appropriate control group

(3) Animal Populations

1048698 Allows for control over ndash Environmental conditionsexperience ndash Size and nature of lesions ndash Genetic differences etc

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

1048698 Only know how brain performs withoutthat particular area

1048698 We can infer the site may be critical but we can not identify all the areas that may be involved

1048698 Site may not be critical in performing a particular function rather may contain axons that connect regions that

must interact for correct performance

ndash Disconnection syndromebull Split brainbull Conduction aphasia

Associated problemsingle cases or groups

1048698 Groups of patients may be so hetergeneous in their behavior that lsquogroup averagersquo is meaningless

ndash Argues for single case approach

1048698 Problem with single case approachndash Is pattern observed representative of people in

generalndash Does not allow one to rule out random error

1048698 Use multiple case approach validating research findings on a series of patients or

1048698 Follow-up findings from single-case withgroup studies

(2) Neurologically intactIndividuals

1048698 These persons provide the control group that allows us to determine thedegree to which performance of brain damaged people is compromised

1048698 Well-designed studies must include appropriate control group

(3) Animal Populations

1048698 Allows for control over ndash Environmental conditionsexperience ndash Size and nature of lesions ndash Genetic differences etc

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

Associated problemsingle cases or groups

1048698 Groups of patients may be so hetergeneous in their behavior that lsquogroup averagersquo is meaningless

ndash Argues for single case approach

1048698 Problem with single case approachndash Is pattern observed representative of people in

generalndash Does not allow one to rule out random error

1048698 Use multiple case approach validating research findings on a series of patients or

1048698 Follow-up findings from single-case withgroup studies

(2) Neurologically intactIndividuals

1048698 These persons provide the control group that allows us to determine thedegree to which performance of brain damaged people is compromised

1048698 Well-designed studies must include appropriate control group

(3) Animal Populations

1048698 Allows for control over ndash Environmental conditionsexperience ndash Size and nature of lesions ndash Genetic differences etc

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

1048698 Use multiple case approach validating research findings on a series of patients or

1048698 Follow-up findings from single-case withgroup studies

(2) Neurologically intactIndividuals

1048698 These persons provide the control group that allows us to determine thedegree to which performance of brain damaged people is compromised

1048698 Well-designed studies must include appropriate control group

(3) Animal Populations

1048698 Allows for control over ndash Environmental conditionsexperience ndash Size and nature of lesions ndash Genetic differences etc

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

(2) Neurologically intactIndividuals

1048698 These persons provide the control group that allows us to determine thedegree to which performance of brain damaged people is compromised

1048698 Well-designed studies must include appropriate control group

(3) Animal Populations

1048698 Allows for control over ndash Environmental conditionsexperience ndash Size and nature of lesions ndash Genetic differences etc

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

(3) Animal Populations

1048698 Allows for control over ndash Environmental conditionsexperience ndash Size and nature of lesions ndash Genetic differences etc

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

Gathering Information aboutthe BrainTechniques 1048698 CT Scans ndash Uses series of X-ray beams through head Images developed on sensitive film Shows anatomical image

of brain density ndash CSF lt brain tissue lt blood lt bone ndash Darker lt helliphelliphelliphelliphelliphelliphelliphellipgt Lighter

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

1048698 Advantage ndash Can be used with most people

1048698 Disadvantage ndash Uses radiation ndash Dye may cause allergic reaction ndash Results do not have a high spatial

resolution ndash Structure of brain only

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

MRI

1048698 Anatomical image of substances such as water or fat - give picture of tissue density

1048698 Relies on passing an external radio frequencypulse to disrupt the magnetic fields of nucleiand distort the behaviors of atoms

1048698 When atoms fall back in line they re-emit theradio-frequency signal which is detected by areceiver coil

1048698 The frequency of this signal reflects thenumber of elements in the nucleus and theeffect of the surrounding material

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

Advantages

1048698 Does not require X-rays or radioactive

material 1048698 Safe painless non-invasive 1048698 Result is high resolution

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

Disadvantages

1048698 Expensive 1048698 Cannot be used in patients with metallic

devices like clips pacemakers or

possibly orthopedic pins 1048698 Cannot be used with claustraphobic

patients 1048698 Assesses structure only

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

Functional MRI

1048698 In fMRI MR signal measures functional

characteristics of brain 1048698 Detects changes in blood flow to

particular areas of the brain 1048698 Provides both an anatomical and

functional view of the brain

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

Advantages

1048698 Noninvasive - radiation needed 1048698 Multiple scans can be done on an

individual so can examine changes over time (eg learning)

ndash Provides a good measure of brain activity over seconds

1048698 Provides a good spatial resolution

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

Disadvantages

Cannot localize processes in time better

than 1 second

ndash fMRI does not image neural activity but rather response of vascular system to oxygen demand and this can lag functional activation as well as extend beyond period when activation occurred

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

PET

Also provides a functional image of brain activity

1048698 Radioactive substance (eg glucose)

introduced into blood 1048698 Radioactive molecule becomes stable by

releasing positron collides with electron annihilate each other -producing energy - PET detects this energy

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

1048698 PET detects how much of the brain fuel

(oxygen glucose) is being used by different regions

1048698 Areas that are metabolically active emit

lots of energy those that are less active

emit less energy

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

1048698 Advantages Good at examining functioning of a variety of

neurotransmitters

1048698 DisadvantagesInvolves radiationProvides image of brain activity averaged over very long time periods (eg minutes whereas cognitive decisions occur in msec)

Typically data on task is averaged across many people

Not very good at determining location of function in a given person (does not provide high spatialresolution)

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

EEG

1048698 Electrical activity of the brain 1048698 Provides information about general

state of person (eg awake) 1048698 Good at detecting various clinical

disorders

ndash eg sleep seizures

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

1048698 Provides accurate measures of activity

on a millisecond basis 1048698 But poor at localizing activity 1048698 Does not provide information about

subcortical structures

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

Event Related Potentials(ERP) 1048698 Recording of brainrsquos activity that are linked to

the occurrence of an event (stimulus) 1048698 Provides information linked to processes

such as memory and attention 1048698 Examine components of the waveform

recorded on the scalp such as

ndash P300 - S must respond to target stimulus (lsquobrsquo not lsquodrsquo blank sound) - appears to measure attention updating of memory

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

NeuropsychologicalAssessment 1048698 Allows one to separate cognitive functions

(eg STM vs LTM) 1048698 Profile patient strengths and weaknesses

ndash diagnosis 1048698 Provide a baseline to evaluate change

ndash eg remediation improvement decline

1048698 Make statements about prognosis

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

1048698 Fixed batteries

(eg Haltead-Reitan Luria-Nebraska) 1048698 Flexible battery 1048698 Generally measure IQ (Wechsler tests) 1048698 Also measure executive function

attention memory language spatial

ability motor sensory function emotional function

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR

1048698 Need good normative data 1048698 Pre-morbid Estimation

eg NART WTAR