CH. 6 AND CH. 7Body and BehaviorAltered States of Consciousness

THE NERVOUS SYSTEM

• Controls emotions, thinking, movements, and behavior

• Two Parts• Central Nervous System (CNS)- brain and spinal cord

• Peripheral Nervous System (PNS)- smaller nerves that reach other parts of the body

• All parts are protected by sheathing and vertebrae (injury could lead to paralysis)

Nervous System

Central Nervous System

Brain

Spinal Cord

Peripheral Nervous System

Autonomic

Sympathetic

Para-sympathetic

Somatic

NEUROTRANSMITTERS

Neurotransmitter Function Problems Associated

with an Excess or a

Deficit

Acetylcholine Motor Movement Lack of acetylcholine

is associated with

Alzheimer’s disease

Dopamine Motor Movement and

Alertness

Lack of dopamine is

associated with

Parkinson’s disease, an

overabundance is

associated with

schizophrenia

Endorphins Pain control Involved in addictions

Serotonin Mood control Lack of serotonin is

associated with

clinical depression

NEUROTRANSMITTERS

• Norepinephrine- involved with memory and learning

• Endorphins- inhibit pain- “inside morphine”

• Too much or too little is linked to certain diseases• Undersupply of acetylcholine (memory and

movement)- Alzheimer's • Oversupply of dopamine (learning, emotional

arousal)- Schizophrenia• Undersupply of dopamine- Parkinson’s disease• Undersupply of norepinephrine and serotonin-

depression

NEURON ACTIVITY

• Intensity of activity in each neuron depends on how many other neurons are acting on it

• Each individual neuron is either

ON or OFF depending on

whether most of the neurons

acting on it are either exciting

or inhibiting

Stub toe

Sensory neurons in

toe activated

Messages sent to spine

through afferent nerves

Message goes up

spinal cord on

more afferent nerves

Enters brain

stem to sensory cortex

OUCH

Motor cortex sends

messages down spinal cord

(efferent)

Hop up and

down

THE LOBES OF THE BRAIN

• The cerebrum is two hemispheres connected by a band of fibers called the corpus collosum

• Divided into lobes• Occipital- visual

• Parietal- senses from all over the body

• Temporal- hearing, memory, speaking

• Frontal- organization, planning

LEFT AND RIGHT HEMISPHERES

• Properties of the two sides have been simplified

• Complement and help each other

• Each side is connected to one half of the body in a criss-cross pattern

• Left side- speech, math, logic, understanding

• Right side- visual, spatial ability (puzzles), creativity, music

SPLIT BRAIN OPERATIONS

• When people are prone to grand mal seizures, separating the brain hemispheres will make them more severe

• Side effects: seem normal

• … but, if a man whose brain has been split holds a ball in his right hand, he will be able to say it is a ball, but in his left hand, he will not be able to say what it is. Information cannot cross to the speech center in the left hemisphere

STUDYING THE BRAIN

• Recording:

• Inserting electrodes (wires) into the brain- record activity

• EEG- can record activity of large portions of the brain

• Rhythmic pattern that depends on whether a person is awake, drowsy, or asleep

STUDYING THE BRAIN

• Stimulation- causing neurons to fire

• Use during brain surgery to find the malfunctioning part

• By applying an electric current

to the temporal lobe, can

trigger memory sequences

• One woman believed that a

radio was being played in

the operating room

** Pain relief without drugs

STUDYING THE BRAIN

• Lesions- cutting or destroying part of an animal’s brain

• Difference in behaviors

• Removing part of the temporal lobe of monkeys made them less fearful and violent- aggression

• Far more complex than people thought at first

STUDYING THE BRAIN

• Accidents- Phineas Gage

• Railroad foreman who had a 13 pound, three foot long iron bar go through his skull (1848)

• Survived, but suffered personality changes-was short tempered and said inappropriate things

• In 1994, realized that damage had been done to the frontal cortex, which censors

thoughts and ideas

CT Scans: An x-ray of the brain.

A CT scan is essentially a computerized assembly of several x-ray images taken from a series of different angles. With a CT, the resolution is much better than conventional x-rays, and the detail that can be seen is much greater.

**Can pinpoint brain injuries and

deterioration

PET measures the emission of positrons from the brain after a small amount of radioactive isotopes, or tracers, have been injected into the blood stream. A common example is a glucose-relative with embedded fluor-18. With this molecule, the activity of different regions of the brain can be measured. The result is a three-dimentional map with the brain activity

represented by colors.

P

E

T

S

C

A

N

S

MRI is a noninvasive imaging technique that does not use x-

rays. The process involves passing a strong magnetic field through

the head. The magnetic field used is 30,000 + times that of the earth's

magnetic field. It's effect on the body, however, is harmless and

temporary. The MRI scanner can detect radiation from certain

molecules, which are present in different concentrations in different

tissues.

Tumor

HEREDITY AND ENVIRONMENT

• Heredity- the genetic transmission of characteristics from parents to offspring

• Genes- the basic units of heredity, can interact with environment to cause behavior

• Nature vs. Nurture

• Galton- success runs in families

• Watson- “give me a dozen healthy infants and I’ll guarantee to take any one at random and train him to be any specialist I might select”

Sleep is:a state of altered consciousness, characterized by certain patterns of brain activity and inactivity.

vital to mental health.

restorative – it allows the brain to recover from exhaustion and stress while the body conserves energy.

Stages of SleepPrior to sleep, the body temperature decreases, pulse rate drops, and breathing becomes slow and even.

Stage I – pulse becomes even slower, muscles relax, breathing becomes uneven and brain waves become irregular.

Stage II – brain waves will shift in amplitude and frequency, eyes roll from side to side.

Stage III – deeper sleep, large amplitude delta waves sweep across the brain every second.

Stage IV – deepest sleep and difficult to awaken a sleeper in this stage, muscles are even more relaxed, eyes move rapidly (REM), pulse rate and breathing is irregular, levels of adrenal and sexual hormones rise.

* cycle repeats about every 90 minutes

**at no point does the brain become totally inactive

Sleep DisordersInsomnia

Sleep Apnea

Narcolepsy

Nightmares and Night Tremors

Sleepwalking and Sleep Talking

Dreams are the mental activity that takes place during sleep.

Because the amounts of time spent in REM sleep increase during the night, the last dream is likely to be the longest and the one people remember when they wake up.

A large percentage of the emotions experienced in dreams are negative or unpleasant – anxiety, anger, sadness, etc…

Some dreams are negative enough to be considered nightmares.

**end of notes**

Hypnosis is a form of altered consciousness in which people become highly suggestible to changes in behavior and thought.

Participants are NOT put to sleep – it is a form of trance.

Hypnosis has uses in medical and therapeutic settings.

Memory can be aided or enhanced

Pain can be eliminated or reduced

Problems can be revealed and insight gained

Biofeedback is a technique in which a person learns to control physiological processes with the help of feedback.

Can control processes such as heart rate, blood pressure, skin temperature, and sweat-gland activity

Meditation is when a person focuses his or her attention on an image or thought to clear the mind and produce relaxation.

3 typesTranscendental : involves the mental repetition of a mantra

Mindfulness : focuses on the present moment (a Buddhist tradition)

Breath : concentration on respiration – inhaling and exhaling

Psychoactive DrugsInteract with the central nervous system to alter a person’s mood, perception, and behavior.

Range from stimulants (like caffeine in coffee/cola) to depressants (like alcohol) to hallucinogens (like marijuana and LSD).

Enter the blood stream and are taken up in target tissues in various parts of the body

MarijuanaEffects differ from person to person and can be pleasant or unpleasant.

Studies suggest that it is more damaging to the lungs than cigarette use.

Disrupts memory formation, making it difficult to carry out mental and physical tasks.

HallucinogensMain effect is the production of hallucinations.

Also called psychedelics because they create a loss of contact with reality.

The most potent hallucinogen is LSD.

OpiatesUsually called narcotics

Includes opium, morphine, and heroin

Produce analgesia (pain reduction) and euphoria.

AlcoholIs the most widely used and abused mind-altering substance in the U.S.

Effects depend on the amount, frequency, and body weight of the drinker.

Effects are slurred speech, blurred vision, impaired judgment and memory.

Drug Abuse and TreatmentDrug abusers are people who regularly use illegal drugs or excessively use legal drugs.

Risks of abuse are danger of death or injury, damage to health, legal consequences, destructive behavior, and loss of control.

Treatment requires the individual to 1) admit they have a problem

2) enter a treatment program or get therapy

3) join a support group to help reduce the possibility of a relapse.