chapter 6

The Workings of the Mind and Body

Nervous system controls your emotions, movement, thinking and behavior

2 parts: central nervous system (CNS)- the

brain and spinal cord peripheral nervous system (PNS)-

consists of smaller branches of nerves that reach other parts of the body

CENTRAL NERVOUS SYSTEM

PERIPHERAL NERVOUS SYSTEM

Long, thin cells of nerve tissue that send messages to and from the brain; they fire on an “all-or-nothing” principle

Parts of a neuron- cell body, dendrites, axon Cell body-nucleus; produces energy to fuel

activity Dendrites-short, thin fibers that receive

impulses Axon- long fiber that carries impulses towards

the dendrites of the next neuron

Will Explain Why We FEEL……

Pain

Strong

Sick

Nervous

Neuron Structure

Neurons do NOT touch each other- the space in between is call the synapse.

Neurons transmits impulses by releasing chemicals- neurotransmitters that excite or inhibit Norepinephrin- involved with memory and

learning (undersupply = depression) Endorphin- inhibits pain Ecetylcholine- movement and memory

(paralysis and Alzheimer’s) Dopamine- involved in learning, emotional

arousal, and movement (oversupply = schizophrenia, undersupply = Parkinson’s)

Its function is motor movement and maybe memory.

To much and you will….

Not enough and you will….

Lack of ACH has been linked to Alzheimer’s disease.

Its function is motor movement and alertness.

Lack of dopamine is associated with Parkinson’s disease.

Overabundance is associated with schizophrenia.

Function deals with pain control.

We become addicted to endorphin causing feelings.

Function deals with mood control.

Lack of serotonin has been linked to depression.

It is an electrochemical process

Electrical inside the neuronChemical outside the neuron (in the synapse in the form of a neurotransmitter).

The firing is call Action Potential.

The idea that either the neuron fires or it does not- no part way firing.

Like a gun

How Neurons Communicate

Sensory NeuronsMotor NeuronsInter Neurons

Take information from the senses to the brain.

Take information from brain to the rest of the body.

Take messages from Sensory Neurons to other parts of the brain or to Motor Neurons.

Divisions of the Nervous System

Somatic nervous system (SNS)- controls voluntary activities- movement of skeletal muscles

Autonomic nervous system (ANS)- controls involuntary activities such as heartbeat and stomach activity Sypathetic N.S.- “fight or flight”

Flight or Fight Response - prepares body for dealing with emergencies or strenuous activity

works to conserve energy and enhance the body’s ability to recover from strenuous activity

A Simple Reflex

A Simplified Neural Network

Neurons that learn to work together as a team.

AccidentsLesionsCAT ScanPET ScanMRIFunctional

MRI

Hindbrain- rear base of skull; most basic processes of life

Cerebellum- helps control posture, balance and voluntary movements

Medulla- breathing, heart rate and reflexes The pons- bridge between spinal cord and

brain; produces chemicals for sleep Midbrain- small part above the pons;

integrates sensory info and relays it upward

RAS- reticular activation system- alerts the rest of brain to incoming signals

Cerebrum consists of 2 hemispheres connected by a band of fibers- corpus callosum

Cerebral cortex is divided into 4 lobes Occipital lobe- processes visual signals Parietal lobe- processes info from senses from all over

the body Temporal lobe- hearing, memory, emotion and

speaking Frontal lobe- organization, planning and creative

thinking Somatosensory cortex- receives info from touch

sensors Motor cortex- controls fine movement

1. Hindbrain2. Midbrain3. Forebrain

-Cerebral Cortex (part or forebrain)

Structures on top of our spinal cord. Controls basic biological structures.

The brain in purple makes up the hindbrain.

Located just above the spinal cord.

Involved in control of

blood pressureheart rateBreathingReflexes

Located just above the medulla.

Connects hindbrain with midbrain and forebrain.

Involved in facial expressions, produces chemicals for sleep

Bottom rear of the brain.

“little brain”Coordinates

fine muscle movements – posture, balance

Coordinates simple movements with sensory information - RAS- reticular activation system- alerts the rest of brain to incoming signals

controls arousal and ability to focus our attention (important!)

If Destroyed

If stimulated

What makes us human.

Largest part of the brain – central core

.

Maybe most important structure in the brain.

Controls and regulates

Body temperatureSexual ArousalHungerThirstEndocrine System

The most powerful structure in the brain.

Switchboard of the brain.

Receives sensory signals from the spinal cord and sends them to other parts of the forebrain.

Every sense except smell.

Made up of densely packed neurons we call “gray matter”

Glial Cells: support brain cells.

Wrinkles are called fissures.

outer layer; ability to learn and store complex and abstract info and to project thinking into the future

The Cerebral Cortex is made up of four Lobes.

Abstract thought and emotional control.

Contains Motor Cortex: sends signals to our body controlling muscle movements.

Contains Broca’s Area: responsible for controlling muscles that produce speech.

Damage to Broca’s Area is called Broca’s Aphasia: unable to make movements to talk.

Motor and Sensory Cortexes

Contain Sensory Cortex: receives incoming touch sensations from rest of the body.

Most of the Parietal Lobes are made up of Association Areas.

Where would this girl feel the most pain from her sunburn?

Any area not associated with receiving sensory information or coordinating muscle movements.

Motor and Sensory Cortexes

Deals with vision.Contains Visual

Cortex: interprets messages from our eyes into images we can understand.

Process sound sensed by our ears.

Interpreted in Auditory Cortex.

NOT LATERALIZED. Contains Wernike's

Area: interprets written and spoken speech.

Wernike's Aphasia: unable to understand language: the syntax and grammar jumbled.

Specialization and Integration in Language

Brain Activity when Hearing, Seeing, and Speaking Words

The Limbic System

Involved in the processing and storage of memories.

Involved in how we process memory.

More involved in volatile emotions like anger.

The emotion of anger has not changed much throughout evolution.

Pituitary Gland

•“master gland”

•Key hormone is the growth hormone.

•Overproduction may result in

gigantism.

•Major growth in hands, feet, and chin.

Divides the 2 hemispheres.

Divided into to hemispheres.

Contralateral control: right controls left and vice versa.

In general,Left Hemisphere:

logic and sequential tasks.

Right Hemisphere: spatial and creative tasks.

The idea that the brain, when damaged, will attempt to find news ways to reroute messages.

Children’s brains are more plastic than adults.

Left hemisphere Controls right side

of body

Verbal Mathematical Analytical logic

Right hemisphere Controls left side

of body

Nonverbal Spatial/visual Holistic Perception,

patterns Creativity/intuition

•19 men and 19 women asked to determine if two nonsense words rhymed.

•All 19 men had left frontal lobe light up

•11 of 19 women had that plus lighting behind right eyebrow

•Left brain (reason) Right brain (feelings)

•Thus women draw on feelings as well as reason when they use words.

University of Pennsylvania

•37 men and 24 women told to think of nothing while linked to a PET machine

•Men-reported being fixated on sex and football

•Women-fixated on stringing words together, such as “How much longer?”, “Why are we doing this?”

Found that the women’s corpus callosum to be 23% larger than men’s. This may be the reason for more hemispheric chit chat. Also may help explain why women have better intuition.

Baby’s Brain

Genetics make up basic wiring of the brain. Experience makes up the majority. “Live” language boosts

vocabulary. The downside to a baby’s brain is that it is very vulnerable to trauma. Stress produces a hormone called cortisol, which acts like an acid on the brain.

Those who dues to epilepsy, have their corpus callosum removed.

The 2 hemispheres communicate through the corpus callosum

Sometimes necessary to disconnect the 2 sides- severe seizures

Split brain people have difficulty verbalizing objects in the left hand

Injuries to the specific areas of the brain cause personality changes, emotional changes, speech and memory issues, etc.

Testing the Divided Brain

Decreasing Left-handers

Phineas Gage- railroad foreman had temping iron puncture his skull; changed his personality- more aggressive

Lesions- experiments with animals; destroying temporal lobe in rhesus monkeys gave them violent tendencies

Broca’s area- left side of cortex was damaged in his patient- could not produce speech

Electroencephalograph (EEG)- machine used to record electrical activity of the brain

Computerized axial tomography (CAT)- uses x-ray beams (radiation) to study the brain to pinpoint injuries and brain deterioration

Positron emission tomography (PET)- uses radioactive solution to see which brain areas are activated while performing tasks

Magnetic resonance imaging (MRI)- passes non-harmful radio frequencies through the brain to study structure and activity

FMRI- functional MRI uses blood oxygen level

A system of glands that secrete hormones.Similar to nervous system, except hormones work a lot slower than neurotransmitters.

Neurotransmitters

Hormones

The Major Endocrine Glands

Sends chemical messages (hormones) to and from the brain

Hormones- chemical substances - carry messages through the body in blood;

-growth of muscles and bones, metabolic processes, energy, moods, and drives

Neurotransmitters - Send rapid and specific messages

Hormones - Send slow, widespread communication

Nature v. nurtureFlower analogy- genes establish

what you could be and environment defines the final product

Studies done on identical twins raised apart help to show how much of our personality is from genetics and from environment

Consciousness- a state of awareness Sleep Cycles

Stage 1- pulse slows, irregular brain wave activity; drifting; approx. 10 minutes

Stage 2- high amplitude, low frequency wavesStage 3- after 30 minutes; large amplitude

delta wavesStage 4- deepest sleep; large delta waves75% of sleep time is spent in stages 1-4REM sleep- rapid eye movement; high level

of brain activity with deep relaxation of muscles and dreams; lasts 15-45 minutes; run through cycles every 90 minutes

Circadian rhythm- biological clock genetically programmed to regulate physiological responses within 24 hours

How much sleep do you need? Newborns- 16 hrs Teens- 10-11 hrs College age- 8 hrs 70 year olds- 5 hours

Lucid dreaming- you are aware that you are dreaming; day dreaming

Insomnia Sleep apnea

Narcolepsy

Nightmares

Night terrors

Sleep-walking

Failure to get enough sleep

Person has trouble breathing while asleep; affects 1 in 100 Americans

Sudden falling asleep or feeling sleepy during the day

Unpleasant dreams during REM sleep; vivid dreams

Sleep disruptions during stage 4 involving screaming, panic or confusion; no memory of night terror

Walking or carrying out behaviors while sleeping; no memory of doing so

Causes- anxiety, depression, alcohol or drug abuse

Causes- enlarged tonsils, infections of throat/middle ear, obesity

Causes- stress, fatigue, sedative medicines, genetics

Hypnosis- altered consciousness due to narrowed focus; people are highly suggestible to changes in behavior and thought

Franz Anton Mesmer- 1st hypnotistNeodissociation theory- “hidden

observer” part of the personality watches and reports what happens to the hypnotized person

Posthypnotic suggestion- a suggestion made during hypnosis that influences behavior afterward; helpful with unwanted behaviors such as smoking and over eating

Hypnotic analgesia- hypnosis used to reduce pain

Biofeedback- learning to control bodily states with the help of monitoring machines; control brainwaves, heart rate, blood pressure, skin temperature; feedback makes learning possible

Meditation- focusing attention to clear one’s mind and produce relaxation

Transcendental meditation- mental repetition of a mantra; eyes closed 15-20 minutes a day

Mindful meditation- Buddhist tradition; focus on present movement

Breath meditation- concentration on inhaling and exhaling

Meditation has been found to help lower blood pressure, heart rate and respiration rate

How drugs work- Carried by the blood, work like

neurotransmitters at the end of nerve cells to send their own messages

Psychoactive drugs- interact with nervous system and alter consciousness, mood, perception & behavior (caffeine, alcohol, marijuana, LSD)

Marijuana- most often used illegal drug THC- active ingredient Effects vary from person to person-

intensifies sensory experiences, distorts perception of time, intensifies unpleasant feelings, impairs learning, disrupts memory formation

Psychologically addicting Causes lung damage

Hallucinations- perceptions that have no direct external cause

Hallucinogens/psychedelics- drugs that often produce hallucinations; create a loss of contact with reality (LSD)

Opiates/narcotics (opium, morphine, heroin); they produce analgesia- pain reduction, euphoria and constipation; leads to physical addiction; overdose results in loss of control of breathing

Alcohol- most widely used/abused drug; depressant that inhibits brain’s normal functions

Drug category examples effects Negative effects

stimulants Nicotine, caffeine, amphetamines, crystal meth

Increases alertness and energy, excitation, euphoria, confidence

Anxiety, restlessness, irritability, sleeplessness, aggressiveness, feelings of panic

depressants alcohol Relaxation Relieves inhibitions; impairs memory and judgment

tranquilizers Valium, Xanax, barbiturates

Relieves anxiety, relaxes muscles, induces sleep

Impaired coordination, depression, lethargy, drowsiness

opiates/narcotics Morphine, heroin, opium, codeine, vicodin

Euphoria, less sensitivity to pain,

Lethargy, nausea, impaired coordination, unpleasant withdrawal effects

hallucinogens LSD, mescaline Euphoria, changed perception, insightful moments

Nausea, paranoia, panic, jumbled thoughts

Why do people abuse drugs?

What are the dangers?

How can we treat drug abuse?

How can we prevent drug use?

Stimulus- any aspect of or change in the environment to which an organism responds

Sensation- what occurs when a stimulus activates a receptor

Perception- the organization of sensory information into meaningful experiences

Psychophysics- the study of the relationship between stimuli and sensory experiences

Absolute threshold- the weakest amount of a stimulus required to produce a sensation

Difference threshold- smallest change in a physical stimulus that can be detected between two stimuli

Just Noticeable Difference (JND)- smallest increase or decrease in the intensity of a stimulus that a person is able to detect

Weber’s Law- the larger or stronger a stimulus, the larger the change required for a person to notice

Signal-detection theory- humans can choose what stimuli to attend to and block out surrounding stimuli

Sensory adaptation- we respond to and adapt to changes in our environment

The Stroop Effect-

7 senses- vision, hearing, taste, smell, touch, vestibular (balance) & kinesthetic (movement & body position)

Objects look the color of light they reflect; they absorb all other light colors

Blind spot- where optic nerve exits the eyeColor deficient- when cones don’t function

properlyBinocular vision- combining images from

each eye into a single imageRetinal disparity- the differences between

the images which is essential to depth perception

Near sightedness and far sightedness

Loudness- determined by amplitude (height of wave)

Decibel- measure of loudness (sound pressure energy)

Pitch- depends on frequency Deafness- 2 types

Conduction-problems with outer or middle ear when physical motion is hindered; can be helped with hearing aids

Sensorineural- damage to cochlea, hair cells, or neurons

Regulated by vestibular system in the inner ear (fluid)

3 semicircular canalsStimuli for responses- spinning,

falling, tilting head

Gaseous molecules must come into contact with smell receptors in nose

Olfactory nerve carries impulses from nose to the brain

Liquid chemicals stimulate taste bud receptors

4 senses Sour Salty Bitter Sweet

Flavor is a combination of taste, smell and tactile sensations

Receptors responsible for info about pressure, warmth, cold & pain

2 kinds of pain Sharp and localized Dull and generalized

Gate control theory of pain- can lessen pain by shifting attention away from pain impulses or by sending competing signals

Sense of movement and body position

Receptors in muscles, tendons, and joints

It coordinates movement

Gestalt- organizing bits & pieces of information into meaningful wholes Proximity Similarity

Closure Continuity

simplicity

Figure-ground perception- ability to discriminate between a figure and its background

Perceptual inference- filling in gaps in what our senses tell us

Subliminal messages- brief auditory or visual messages presented below the absolute threshold

Motion parallax- the apparent movement of stationary objects relative to one another that occurs when the observer changes position

Constancy- tendency to perceive objects in the same way regardless of changing angle, distance, or lighting

Illusions- perceptions that misrepresent physical stimuli

Extra sensory perception (ESP)- ability to gain information by some means other than ordinary senses