Neuroscience and Behavior

AP Psychology

The Brain

Made up of neurons and glial cells.

Glial cells support neural cells.

Some scientists divide the brain up into three parts. Hindbrain Midbrain Forebrain

Techniques for Studying the Brain

Lesion tissue destruction a brain lesion can be caused naturally

or experimentally Brain tumors also lesion brain tissue

Techniques for Studying the Brain: Less Invasive Ways

Electroencephalogram (EEG) an amplified

recording of the waves of electrical activity that sweep across the brain’s surface

these waves are measured by electrodes placed on the scalp

Less Invasive Ways to Study the Brain

CT (computed tomography) Scan a series of x-ray photographs taken from different

angles and combined by computer into a composite representation of a slice through the body; also called CAT scan

PET (positron emission tomography) Scan a visual display of brain activity that detects where a

radioactive form of glucose goes while the brain performs a given task

MRI (magnetic resonance imaging) a technique that uses magnetic fields and radio

waves to produce computer-generated images that distinguish among different types of soft tissue; allows us to see structures within the brain

Images

Pet Scan of Brain MRI of brain (midsagittal)

CT scan-brain tumor

Brain Structures Brainstem

the oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull

responsible for automatic survival functions

Medulla [muh-DUL-uh] base of the brainstem controls heartbeat and

breathing

The Brainstem Reticular Formation

a nerve network in the brainstem that plays an important role in controlling arousal and the ability to focus attention

Thalamus the brain’s sensory

switchboard, located on top of the brainstem

Receives sensory information in the cortex and transmits replies to the cerebellum and medulla

Parts of the Brain Cerebellum

the “little brain” attached to the rear of the brainstem

it helps coordinate voluntary movement and balance

Limbic System a doughnut-shaped

system of neural structures at the border of the brainstem and cerebral hemispheres

associated with emotions such as fear and aggression and drives such as those for food and sex

includes the hippocampus, amygdala, and hypothalamus.

Amygdala two almond-shaped

neural clusters that are components of the limbic system

Emotional control center Memory

•Hippocampus-involved in memory processing

Brain Structures

Hypothalamus neural structure lying below (hypo) the

thalamus; directs several maintenance activities

Hunger (eating) Thirst (drinking) body temperature Sexual arousal (libido)

helps govern the endocrine system via the pituitary gland

is linked to emotion

Pituitary gland

Hypothalamus

Brain Structures: The Cerebral Cortex

Top layer of our brain. Contains wrinkles called fissures. The fissures increase surface area of our

brain. the body’s ultimate control and

information processing center

The Cerebral Cortex

Divided into eight lobes, four in each hemisphere (frontal, parietal, occipital and temporal).

Any area not dealing with our senses or muscle movements are called association areas.

The Cerebral Cortex Frontal Lobes

involved in speaking and muscle movements and in making plans and judgments

Contains Broca’s area (speech production) Parietal Lobes

include the sensory cortex Occipital Lobes

include the visual areas, which receive visual information from the opposite visual field

Right half of each retina goes to left occipital lobe and vice versa

Temporal Lobes include the auditory areas (process sound) Contains Wernicke’s area (comprehension of

speech/language development)

The Cerebral Cortex

The Cerebral Cortex

Motor Cortex area at the rear of the frontal lobes that

controls voluntary movements Sensory Cortex

area at the front of the parietal lobes that registers and processes body sensations

Aphasia (Disorders) impairment of language, usually caused by left

hemisphere damage either to Broca’s area (impairing speaking) or to Wernicke’s area (impairing understanding)

The Cerebral Cortex

Association Areas More intelligent animals have

increased “uncommitted” or association areas of the cortex

Specialization and Integration

Brain Plasticity

The ability for our brains to form new connections after the neurons are damaged. the brain’s capacity for modification, as evident

in brain reorganization following damage The younger you are, the more plastic your brain

is.

Announcement!

Your test will be Friday & Monday Multiple Choice –Friday Essay-Monday

I will check reading notes Thursday Brain Models/Mobiles will be due

Thursday!

Our Divided Brain

Corpus Callosum large band of

neural fibers connects the

two brain hemispheres

carries messages between the hemispheres

Corpus callosum

Our Divided Brain Images from the left

visual field go to the brain’s right hemisphere

Images from the right visual field go to the brain’s left hemisphere.

Left hemisphere controls the right hand & vice versa

The left hemisphere is dominant for language Broca’s, Wernicke’s,

angular gyrus

Our Divided Brain

Left Hemisphere Controls speech muscles Comprehension/

understanding of speech & writing

Regulation of positive emotions

Memory of words and numbers

Spontaneous speaking and writing

Logic & analytic thought Science and math

Right Hemisphere Regulation of negative

emotions Responses to simple

commands Memory for shapes and

music & creativity Interpreting spatial

relationships & visual images

Recognition of faces

Split Brain

a condition in which the two hemispheres of the brain are isolated by cutting the connecting fibers (mainly those of the corpus callosum) between them Procedure done to treat severe

epileptic seizures

So what happens to a “split brain”?

When a split brain patient is asked what he sees, the left hemisphere sees the ring on the right side of the screen and can verbally say “ring”.

The right hemisphere sees the left side of the screen, but cannot verbalize (say) what is seen (key). However, the patient can pick up the correct object using the left hand.

Genetics Every human cell contains 46 chromosomes (23

pairs). Made up of genes.

Made up of deoxyribonucleic acid- DNA. Made up of nucleotides.

Your DNA (chromosomes) is found in the nucleus of every cell in your body.

Your genotype is the genetic pattern that makes you different from anyone else Ex. Brown eyes- Bb or BB; blue eyes-bb

Your phenotype is your observable characteristics Ex. You have brown eyes, blue eyes, tall, short

Sex chromosomes (23rd pair) XX-female; XY male Father determines sex of child because he can

donate an X or Y.

Twins

Monozygotic twins- identical twins Results from one zygote (fertilized egg)

dividing into two Each new zygote has the same chromosomes

& same genes on each chromosome

Dizygotic twins- fraternal twins Results from two separately fertilized eggs

developing at the same time in utero Resulting twins are no more similar

genetically than any other pair of siblings

Twins and Psychology

Best way to really study genetics because they come from the same zygote.

Bouchard Study .69 Correlational coefficient

for IQ tests of identical twins raised apart.

.88 raised together.