AP Psych Unit 1

nature

genes, heredity

nurture

environment, culture, parents, peers

behavioral genetics

study of the relative power and limits of genetic and environmental influences on behavior; studies the interplay of nature and nurture

heredity

transmission of genes from parents to offspring

genome

complete set of genetic material that blueprints cell design and function

genetic predisposition

an increased chance or likelihood of developing a particular disease based on the presence of genetic variants and/or a family history suggestive of an increased risk of the disease

evolutionary psychology

the study of the ways in which the mind is shaped by pressures to survive and reproduce

natural selection

concept that traits which enable survival and reproduction will be passed to succeeding generations

eugenics

study of how to arrange reproduction within a human population to increases the occurrence of heritable characteristics regarded as desirable; term coined by Francis Galton in the 1800s; influenced by Darwin and his theory of natural selection

selective breeding

encouraging higher reproductive rates of people with “superior” traits and reducing rates in those with “inferior” traits

twin studies

allow scientists to isolate nature and nurture influences; identical twins are much more similar in all areas than fraternal twins (in terms of intelligence, predisposition to behaviors, temperament)

identical vs fraternal twins

monozygotic, one egg split, same sex only VS. dizygotic, two eggs at the same time, same or opposite sex

adoption studies

comparing adopted child/adoptive parent or adopted child/biological parent to assess genetic and environmental influences on behavior

heritability

the extent to which genetic individual differences contribute to individual differences in an observed behavior (focuses on nature); as environments become more similar, heritability increases & as environments become more diverse, heritability decreases

prenatal nurture

mother’s placenta gives the fetus nourishment, as well as can transfer toxic agents that can affect development and growth

epigenetics

the study of environmental influences on gene expression that occur without a DNA change (how heredity and environment work together)

experience & brain development

experience reflects on brain size and complexity (Rosenzweig rat experiment); babies who are handled (especially premature babies) develop faster than non-handled babies; evidence is found in prenatal units - mothers hold premature babies to speed development and growth; use it or lose it – stimulation is essential for brain development & maintenance! "Our genes dictate overall brain architecture, but experience directs the details."

psychology

the scientific study of behavior and mental processes

the nervous system

the body’s electrochemical communication network of neural cells

Central Nervous System (CNS)

the brain and spinal cord; centrally located in the body; communication highway between the rest of the brain and the brain; made of interneurons

Peripheral Nervous System (PNS)

the nerves that connect the CNS to the rest of the body; outside of (peripheral) to the brain and spinal cord; nerves made of sensory and motor neurons

nerves

neural cables/bundles that connect the CNS to muscles, glands, and sense organs (ex: optic nerve connecting the eye to the brain; eye=sense organ, optic nerve=PNS, brain=CNS)

sensory neurons (feel)

in the PNS; carry incoming information from the senses to the CNS

interneurons (interpret)

in the CNS; internally communicate between sensory inputs and motor outputs

motor neuron (move)

in the PNS; carry outgoing information from the CNS to muscles and glands

spinal cord

the “highway” between the brain and the PNS; however, sometimes the body can sense stimuli and react without the message reaching the brain first

reflex

an involuntary response to a stimulus that happens without conscious thought; reflex pathway = 1 sensory neuron + 1 communication interneuron + 1 motor neuron; (ex: withdrawal reflex, knee-jerk reflex)

somatic nervous system

controls the body’s skeletal muscles for voluntary movements (ex: running, dancing, using ASL, etc)

autonomic nervous system

controls the glands and the involuntary muscles of internal organs (ex: heartbeat, digestion, breathing, sweating, etc)

sympathetic

one way of the autonomic nervous system; arouses the body memory aid: when someone is in crisis, we feel sympathy for them and are alerted to action; “fight or flight”

parasympathetic

another way of the autonomic nervous system; calms the body; memory aid: parasympathetic - paralyzing; “rest & digest”

neuron

nerve cell; building block of the nervous system; found all over the body-brain, legs, eyes; anywhere there are nerves

dendrite

the branchy extensions of a neuron that receive chemical messages

soma

cell body: contains all the components of a typical animal cell (nucleus, ribosomes, mitochondria, etc)

axon

the extension of a neuron through which electrical messages pass; like the “backbone” of a neuron- if severed, the neuron cannot function and may die

Myelin Sheath

layer of fatty tissue that insulates the axon for protection and to speed up neural impulses (the “message”)

glial cells

cells that provide nutrition, protection and stick to one another to bind neurons together

Multiple Sclerosis (MS)

a chronic autoimmune disease that affects the central nervous system (brain and spinal cord); causes breakdown of the protective covering of nerves

axon termials

branches at the end of an axon that send messages to the dendrites of another neuron; the end of these branches contain vesicles which house molecules called neurotransmitters

action potential

a brief electrical charge that travels down the axon; a neuron fires an impulse when it receives a signal from chemicals sent by another neuron

threshold

the level of stimulation required to trigger an action potential; the dendrites receive messages to make the neuron electrically fire or not, depending on the type of chemical received; the chemical stimulation must cross the threshold for an action potential to occur

“all-or-nothing” principle

a neuron either fires or doesn’t fire; not a halfway thing

resting potential

the electrical charge of a neuron at rest

action potential process

1) resting potential (Neuron is at rest; Inside is negative, outside is positive)
2) threshold is reached (a stimulus makes the neuron less negative; if it hits -55mV, the neuron fires)
3) depolarization (sodium (Na⁺) rushes in; inside becomes positive)
4) repolarization (potassium (K⁺) flows out; inside becomes negative again)
5) hyperpolarization (too much K⁺ leaves; neuron becomes extra negative for a short time)
6) refractory period (neuron resets using the sodium-potassium pump; it cannot fire again until it's back to normal)

synapse

the junction between neurons (aka: synaptic gap, synaptic cleft); less than a millionth of an inch wide

neurotransmitters

chemical messengers that travel across the synapse between neurons

step 1: action potential reaches the axon terminals
step 2: vesicles in axon terminals release neurotransmitters (chemicals)
step 3: neurotransmitters travel across the synapse
step 4: neurotransmitters bind/connect to specific receptor sites on the next neuron’s dendrites

“lock-and-key” relationship

between a neurotransmitter and its receptor site on a dendrite

acetylcholine (ACh)

a neurotransmitter functioning muscles, learning/memory, attention (ex: too little is linked to Alzheimer’s disease and myasthenia gravis)

dopamine

a neurotransmitter functioning pleasure/reward, mood, emotion, attention (ex: too little is linked to Parkinson’s disease & too much is linked to schizophrenia, drug addiction)

serotonin

a neurotransmitter functioning mood regulation, hunger, sleep (ex: too little causes depression and mood disorders & too much causes hallucinations)

norepinephrine (aka: noradrenaline)

a neurotransmitter functioning arousal, alertness (especially in fight or flight response) (ex: too little causes depression)

endorphins (endogenous morphine)

a neurotransmitter functioning pain control, stress reduction, positive emotions (ex: too little causes hypersensitivity to pain & too much causes hyposensitivity to pain)

substance p

a neurotransmitter functioning pain perception and signaling (ex: too much causes chronic pain)

GABA (gamma-aminobu tyric acid)

a neurotransmitters functioning sleep regulation/wake cycles and inhibitory properties (calms neural activity) (ex: too little causes sleep disorders, eating disorders & too much caused epilepsy, Huntington’s disease & alcohol increases GABA activity - slowed brain activity)

glutamate

a neurotransmitter functioning long-term memory, learning, excitatory properties (stimulates neural activity) (ex: too much causes migraines, seizures & alcohol decreases glutamate activity - block new memories “blackout drunk”)

agonist

a chemical that acts like a neurotransmitter and boosts its effect (ex: black widow venom mimics ACh → causes muscle spasms; marijuana mimics cannabinoids → causes relaxation)

antagonist

a chemical that blocks a neurotransmitter and stops it from working (ex: botulinum toxin blocks ACh → causes paralysis; alcohol blocks glutamate → slows brain activity, can cause blackouts)

reuptake

the process where the sending neuron takes back leftover neurotransmitters from the synapse; reuptake inhibitors stop this from happening → keeps more neurotransmitters in the synapse longer; SSRIs (like Prozac) block serotonin reuptake → used to treat depression

neuron communication

inside a neuron: electrical (action potential)

between neurons: chemical (neurotransmitters)

endocrine system

the body’s “slow” chemical communication system made of glands that secrete hormones into the bloodstream

hormone

chemical messengers manufactured by glands; travel slowly in the bloodstream; when hormones impact the brain, they trigger interest in sex, food, aggression, “fight or flight”, etc

gland

an organ in the body that secretes a substance for use somewhere else in the body

pituitary gland

located in the limbic system of the brain, this is the “master” gland – it secretes many hormones that stimulate other glands to function; secretes human growth hormone (important during childhood and puberty) among other hormones; acts as a liaison between the brain and endocrine system; controlled by the hypothalamus (acromegaly - caused by a tumor on the pituitary gland)

adrenaline

the “fight or flight” hormone - activates your sympathetic nervous system in times of physical or mental stress; triggers responses such as increased heart rate, decreased digestion, elevated blood sugar

leptin

the “starvation” hormone – signals the hypothalamus that the body has enough fat stored to function normally; when leptin levels are high, appetite is inhibited (and vice versa when low)

ghrelin

the “hunger” hormone – stimulates your body’s appetite; secreted in an empty stomach to initiate eating behavior

melatonin

the “sleep” hormone; secreted by pineal gland in response to circadian rhythms and environmental cues; also regulates puberty and ovarian cycles

oxytocin

the “companionship” hormone – affects social behaviors and parental drives (love & bonding)

psychoactive drug

a chemical substance that alters behaviors and mental processes; work in the synapse between neurons in the brain by stimulating, inhibiting, or mimicking neurotransmitters; effects also influenced by expectations

addiction

craving for a chemical substance despite its adverse effects

substance use disorder

continued substance craving and use despite significant life disruption and/or physical risk

tolerance

the diminishing effect with regular use of the same dose of a drug requiring the user to take larger and larger doses before experiencing the drug‘s effect

withdrawal

the discomfort and distress that follows discontinuing the use of an addictive substance (aches, nausea, distress)

depressants

psychoactive drugs that reduce/depress neural activity and slow bodily functions

alcohol

a depressant; immediate/acute - slowed motor and cognitive functions, less inhibition, impaired judgement, memory loss; chronic - tolerance, liver and brain damage; GABA agonist (calms brain activity/ “passing out”) & glutamate antagonist (calms memory center of brain/ “blacking out”)

heroin (opioids/morphine are essentially identical)

a depressant; immediate/acute “rush” of euphoria, drowsiness, slowed neural functioning and breathing; chronic - tolerance, brain damage; dopamine cannot return to sending neuron → excess dopamine in synapse → reuptake inhibitor for dopamine

stimulants

psychoactive drugs that stimulate/excite neural activity and speedbup bodily functions

caffeine

a stimulant; immediate/acute - alertness, restlessness, irritability, dehydration, headaches; chronic - tolerance, high blood pressure, ulcers, insomnia, infertility, anxiety; adenosine antagonist → more alertness

cocaine

immediate/acute - “rush” of euphoria, loss of appetite, aggressive behavior, hyperstimulation; chronic - tolerance, heart/blood vessel damage, nasal cavity damage, tooth decay; dopamine cannot return to sending neuron → excess dopamine in synapse → reuptake inhibitor for dopamine

hallucinogens

psychoactuve drugs that distort perception and create hallucinations (perception of sensory experience without sensory input)

marijuana (also a depressant)

immediate/acute - relaxation, euphoria, loss of short-term memory, paranoia, hallucinations, lowered reaction time, sexual dysfunction; chronic - hindered brain development if used heavily in adolescence (memory, learning, impulse control); THC = cannabinoid agonist → dopamine floods synapse (cannabinoid turn off release of neurotransmitter that blocks dopamine activity → more dopamine)

the brain

brain size doesn’t equal intelligence; brain structure and complexity = intelligence

older brain structures

perform unconscious simple tasks necessary for survival (breathing, coordinating movement, heartbeat); brainstem, thalamus, cerebellum

brainstem

responsible for automatic survival functions (breathing, heartbeat); oldest part and central core of the brain; begins where the spinal cord swells as it enters the skull

medulla (part of brainstem)

performs vital autonomic functions (breathing, heart rate, blood pressure)

reticular activating system (part of brainstem)

circuit of neurons that coordinate sleep and wakefulness

thalamus

the brain’s sensory switchboard, located on top of the brainstem; all sensory input (except smell) is directed to the thalamus first; it discerns what type of sensory input is present and then directs it to the appropriate area in the brain

contralateral hemispheric organization

each hemisphere of the thalamus and cerebrum controls/represents the opposite side of the body; takes in stimuli from the opposite side of the body

cerebellum

the “little brain” attached at the rear of the brainstem; processes sensory input, coordinates movement output and balance; an injured cerebellum would cause difficulty walking and keeping balance → jerky movements

the limbic system

group of brain structures responsible for emotions, memories, and smell (consists if hippocampus, amygdala, hypothalamus)

hippocampus

processes/stores memories; amnesia can rsult from injury to the hippocampus

amygdala

two lima bean-sized structures above the hippocampus that influence fear and aggression; size is positively correlated with aggression across species; emotional problems result from which part of the amygdala is stimulated/damaged (too much aggression, no fear, no emotions, etc)

hypothalamus

‘below’ the thalamus; directs “maintenance” (homeostasis) activates and controls the pituitary gland; the “four F’s” → fight/flight/feed/fornication (mate); body temperature; interprets emotions and tells the pituitary gland which glands need to secrete hormones; reward/pleasure center - many dopamine producing neurons

cerebral cortex (outer “gray matter” layer)/ cerebrum

the layer of interconnected neural cells that covers the cerebral hemispheres; responsible for all higher level functions; fissures represent complexity - 80% of the brain is cortex (had to develop confined inside the skull); like the bark on a tree - a thin surface that covers the brain hemisphere

lobes of the brain

geographical subdivisions if the cerebral cortex separated by prominent fissures (folds) in the brain; consists of frontal, parietal, occupital, temporal

frontal lobe

behind the forehead; involved in speaking, muscle movements, making plans/judgments, and “personality”

parietal lobe

at the top rear of the head; recieves sensory input for touch and body position

occipital lobe

at the back of the head; includes the visual cortices, which receive visual information from the opposite visual field

temporal lobe

roughly above the ears (near the “temples”); includes auditory cortices, which receive auditory information primarily from the opposite ear

cortices of the brain

areas of the cerebral cortex responsible for specific purposes (motor, sensory, visual, auditiry)