ch. 6 and ch. 7
TRANSCRIPT
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
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T
S
C
A
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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.