U1a AP Psych In-Class Notes: Biological Structures

Psychology Unit 1A Notes

• Biological School

  • There is a biological explanation for everything in behavior and mental processes (psychology)

  • Tumors can change physical things in the brain and characteristics of the person

STUDY FUNCTIONS

• Acetylcholine (ACH)

  • Produces muscle action & contractions

  • Also involved in memory formation, learning & general intellectual functioning

  • Lack of ACH has been linked to Alzheimer’s disease and paralysis

  • Too much ACH has been linked to violent contractions/spasms

• Dopamine

  • Involved in voluntary muscle movements, attention, learning memory, emotional arousal & rewarding sensations

  • Lack of dopamine has been linked to parkinson’s disease

  • Too much has been linked to addiction, schizophrenia or schizophrenic-like symptoms such as hallucinations and perceptual disorders

• Serotonin

  • Involved in moods, sleep, and wakefulness, eating & aggressive behaviors

  • Lack of serotonin has been linked to depression, anxiety, insomnia, ocd.

• Endorphins

  • Present in opiods and when you exercise

  • Involved in pain control

  • Released during aerobic exercise & liked to positive emotions (i.e. “runners high”) 

  • Not enough endorphins can cause the body to experience pain

  • Too much endorphins may not give adequate warning about pain. You can have a artificial high

    • Many of most addictive drugs deal with endorphins

• Norepinephrine 

  • Used for arousal in the fight/flight response when in danger.

    • Adrenaline is a hormone, norepinephrine is a neurotransmitter; same chemical different jobs 

  • Also involved in stress, arousal, and eating.

  • Lack of Norepinephrine has been linked to depression.

  • Too much Norepinephrine has been linked to anxiety, stress, and nervous tension.

• Gamma-Aminobutyric Acid (GABA)

  • Makes you sleep

  • An inhibitory neurotransmitter

  • Helps balance and offset other excitatory messages.

  • Regulates sleep-wake cycles.

  • Lacking GABA can cause anxiety, seizure, tremors, or insomnia

  • Too much GABA can cause sleeping disorders or some eating disorders

• Glutamate

  • Sensory information \/

  • Enhances transmission  of information to brain

  • Too much Glutamate can cause seizures or migraines because the brain is overstimulated

• Substance P

  • Pain perception and the immune system

  • Too much substance p can cause chronic pain

  • Gives you pain feelings

Drugs

• Psychoactive Drug

  • A chemical substance that alters perceptions and mood (Change consciousness)

• Tolerance 

  • Diminishing effect with regular use of the same dose of a drug, requiring the user to take larger and larger doses before experiencing the drugs effect

  • People use drugs/alcohol to feel normal again

• Withdrawal

  • The discomfort and distress that follow discontinuing the use of an addictive drug

• Physical Dependence

  • Physiological need for a drug

  • Marked by unpleasant withdrawal symptoms

• Psychological dependence 

  • A psychological need to use a drug

  • For example, to relieve negative emotions

How drugs work:

1.  Agonists: Bind to receptor sites and mimic neurotransmitters

2. Antagonists: bind to receptor sites and prevent neurotransmitters from binding

3. Reuptake inhibitors: doesn’t allow the axon terminal to suck up the excess neurotransmitters leftover in the synapse

Types of Psychoactive Drugs

• Depressants: Slowdown the activity of the central nervous system

  • Includes alcohol, barbiturates, opiates

  • Barbiturates (tranquilizers)

    • Drugs that depress the activity of the central nervous system, reducing anxiety but impairing memory and judgment

      • Nembutal, seconal, amytal, valium

    • Prescribed as sleeping pills, reduce respiration, reduce blood pressure, reduce heart rate and reduce REM sleep

  • Opiates

    • Opium and its derivatives (such as morphine and heroin)

    • Opiates depress neural activity temporarily lessening pain and anxiety

  • Analgesic = painkiller/drug that relieves pain

• Stimulants: Excited behavioral and mental activity, Speed up body functions

  • Caffeine, nicotine, amphetamines, cocaine

  • Amphetamines

    • Drugs that stimulate neural activity, casing speeded up body functions and associated energy and mood changes

      • Adderall, Ritalin, Dexedrine

        • Prescribed for ADHD, weight loss, narcolepsy, decongestion

  • Methamphetamines

    • A powerfully addictive drug that stimulates the central nervous system, with speeded-up body functions and associated energy and mood changes; overtime, appears to reduce baseline dopamine levels.

    • Crystal-like powdered substance, rock-like solid chunks

    • Short rush/flash usually creates long binges

  • Caffeine 

    • Reduces drowsiness, improves problem-solving ability, induces anxiety, causes tremors, elevated moods, improved memory, increase in attention

    • Withdrawal symptoms include fatigue and headaches

  • Nicotine

    • Elevated moods, improved memory, increase in attention 

    • Major risk for cancer and heart disease

    • Strong psychological and physical withdrawal symptoms

  • Cocaine

    • Causes self-confidence, euphoria, optimism

    • Short high increases short term tolerance

    • Crack (cocaine, ammonia, water, baking soda) is fast-acting potent, solid

    • High potential for physical and psychological dependence

  • Ecstasy (MDMA = methylenedioxymethamphetamine)

    • Hallucinogenic amphetamine

    • Visual hallucinations, hyperactivity, fatigue, poor concentration

    • Long term effect include permanent brain damage and panic disorder

• Hallucinogens (Psychedelics): Psychedelic (mind-manifesting) drugs that distort perceptions and evoke sensory images in the absence of sensory input

  • LSD, psilocybin, marijuana

  • LSD (Acid)

    • Lysergic acid diethylamide

    • Most powerful hallucinogenic drug

    • Short term memory loss, paranoia, flashback, panic attacks

    • Low potential for physical or psychological dependence

  • THC 

    • The major active ingredient in marijuana 

    • Triggers a variety of effects, including mild hallucinations, euphoria, relaxation, time distortion, short term memory loss moderate potential for psychological dependence

Reflexes: a simple automatic, inborn response to a sensory stimulus

• Normally, sensory (Afferent) neurons take info up through spine to the brain

• Some reactions occur when sensory neurons reach just the spinal cord. The spinal cord sends the reflex signal back.

• Survival adaptation

• Reflexes come from the spine not brain

The Nervous System

• Central Nervous System

  • Brain and spinal cord

  • CNS

• Peripheral nervous system

  • All nerves that are not encased in bone

  • Everything but the brain and spinal cord

  • Is divided into two categories… somatic and autonomic

    • Somatic nervous system

      • Controls voluntary muscle movement

      • Uses motor (efferent) Neurons

    • Autonomic nervous system

      • Controls automatic functions of the body

      • Divided into two categories… the sympathetic and parasympathetic

      • Parasympathetic Nervous system: Automatically slows the body down after a stressful event. Heart rate and breathing slow down, pupil constrict and digestion speeds up. Calms you down

      • Sympathetic nervous system: flight or flight response, adrenaline is secreted, automatically accelerates heart rate, breathing, dilated pupils, slows down digestion

Endocrine System

• System of glands that secrete hormones

• Controlled by the hypothalamus

• Ovaries and testes

• Adrenal gland

• The body’s “slow” chemical communication system

• A set of glands that secrete hormones into the bloodstream

• Hormones

  • Chemical messengers, mostly those manufactured by the endocrine glands that are produced in one tissue and affect another

  • Work the same as neurotransmitters

• Pituitary gland

  • Under the influence of the hypothalamus, the 1) pituitary regulates growth and 2) controls other endocrine glands, “Master Gland” small bean shaped unit, located in the base of the brain

SKIP OVER SOME COME BACK

The Cerebrum: The largest and most complex part of the human brain. It includes the brain areas that are responsible for the most complex mental activities: learning, remembering, thinking & consciousness itself.

Cerebral Cortex:

• Top layer of our brain

• Contains wrinkles called fissures

• The fissures increase surface area of our brain

• Laid out it would be about the size of a large pizza -- folded like marie kondo

• Motor cortex

  • Motor cortex = voluntary movement (frontal lobe)

  • Area at the rear of the frontal lobes that controls voluntary movements

• Sensory Cortex

  • Sense of touch 

  • At the front of the parietal lobes that registers and processes body sensations

    • Located at top of ead

    • Made up of association areas

Hemispheres:

• Divided into a left and right hemisphere

• Contralateral controlled-left controls right side of body and vice versa

• Brain lateralization (processed on opposite sides of the brain)

• Left brain controls language

Split-Brain Patients

• Corpus Callosum attaches the two hemispheres of cerebral cortex

• When removed you have a split-brain patient

• Certain types of people with epilepsy were treated by cutting the cerebral cortex in the past (not practiced anymore)

• Left brain talks while right brain goes along with it

Areas of the Cerebral Cortex:

• Divided into eight lobes, four in each hemisphere (frontal, parietal, occipital, and temporal (near temples) -- two of each of the four, one for each hemisphere)

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

Association Areas: More intelligent animals have increased “uncommitted” or association areas of the cortex. (Differences in intelligence between rats, cats, chimpanzees, and animals)

Frontal lobe:

• Deals with decision making, problem solving, reasoning, planning, personality, and language

• Contains Motor Cortex

  • Area at the rear of the frontal lobes that controls voluntary movements

• Contains Broca’s Area

  • Controls the muscles in our mouth involved in speech

  • Broca's Speaks Wernicke Listens

  • Aphasia is when you can’t communicate due to neurological damage, loss of ability to understand or express speech 

• At the front of the parietal lobes that registers and processes body sensations

• Temporal Lobes

  • Process sound sensed by ears

  • Not laterized

  • Contains wernicke's area

    • responsible for interpreting written or spoken speech

    • Wernicke aphasia 

      • Unable to understand language

Occipital lobes:

• In the back of our head

• Takes care of visual input

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

Specialization and integration

Genetics (review genetics slide & after -- not below)

• Darwin (theory of evolution, went to galapagos and studied animals)

• Natural Selection (Darwin’s survival of the fittest)

• Nature vs Nurture

• Behavior Genetics

• Evolutionary Psychology

• Female chromosomes (xx) and male chromosomes (xy)