bio bio bio bio bio

when the missed roll it in, you were sin

evolutionary psychology

the study of how natural selection influences behavior

heredity (nature)

how genes affect behavior

environment (nurture)

how everything nongenetic influences behavior (school, upbringing, etc.)

twin / adoption studies

showed how identical twins have higher likelihood of developing the same disease (genetics), but they show differences if raised in different situations (environment)

central nervous system

brain and spinal cord

peripheral nervous system

the rest of the nervous system apart from CNS; relays info to the CNS

somatic nervous system

involved with voluntary movement; has sensory and motor neurons

autonomic nervous system

involved in involuntary organs (heart, lungs)

sympathetic nervous system

fight-or-flight; typically activates everything except for digestion

parasympathetic nervous system

rest and digest; typically inhibits everything except for digestion

neuron

basic cell of the nervous system

dendrites

part of the neuron that receives incoming neurotransmitters

axon

part of neuron that the action potential travels down

myelin sheath

covers axon to speed up AP transmission and protect the axon

synapse

the gap between neurons

sensory neurons

afferent; arrive at the brain; receives sense signals from the environment

motor neurons

efferent; exits the brain; sends signals to move

interneurons

neurons in the CNS that transmit messages between the other two and are responsible for the reflex arc

reflex arc

important stimuli that skips brain and routes through spinal cord for immediate reactions (get hand off of hot iron)

glia/glial cells

“glue” cells; provide the myelin for myelin sheaths; clean up waste around neurons; provide nutrients

action potential (AP)

neuron receives stimulus, causes inside of cell to become more positively charged than the outside; ions move across membrane; sends electrical charge down the axon; via depolarization

soma

cell body

nucleus

in cell body, controlling cell function and regulation

terminal sac

holds neurotransmitters in the terminal axon

nodes of ranvier

gaps in myelin sheath where axon is exposed to the cell

resting potential

unequal distribution of ions, where more sodium is outside the cell and more potassium is inside the cell, maintains a stable, negative charge of -70mv across the cell membrane when not actively transmitting signals

depolarization

the inside of the neuron becomes less negative compared to the outside because of an influx of + ions (sodium) through the membrane’s ion channels. the change in elec charge causes the firing of an AP

threshold (of depolarization)

level of stimulation required to trigger an AP in the neuron. minimum needed to produce a response

all-or-nothing principle

neuron will fire at full strength when it reaches its threshold; response will not increase in intensity or speed if the stimulus is stronger; below threshold means no AP at all

refractory period

brief period following AP; neuron can’t generate another AP, needs to rest and reset first. neuron’s sodium channels are temporarily deactivated and the cell membranes return to resting state

neurotransmitters

chemical messengers sent and received by neurons across synaptic gap; allows for nervous system communication

excitatory neurotransmitters

increases likelihood of firing an AP in receiving neuron; binds to receptor sites, prompting an AP

inhibitory neurotransmitters

decreases likelihood of firing an AP

GABA

major inhibitory NT; undersupply linked to seizures, tremors, and insomnia

glutamate

major excitatory NT involved in memory; oversupply overstimulates the brain, causing migraines and seizures

dopamine

both ex and in NT; influences movement, learning, attention, and emotion; short-term reward and fine movement; associated with addiction (found in hypothalamus); oversupply linked to schizophrenia; undersupply linked to tremors and decreased mobility (parkinson’s)

serotonin

long-term moods, emotion, sleep, hunger, arousal, found in amygdala; undersupply associated with depression (some drugs that raise serotonin levels are used to treat depression)

acetylcholine (ACH)

muscle action, learning, memory, in hippocampus; ACh-producing neurons deteriorate with Alzheimer’s disease

norepinephrine

controls alertness and arousal within the sympathetic nervous system; undersupply can depress mood/is linked to depression

endorphins

influences perception of pain or pleasure/decreases pain; oversupply via opioids can suppress body’s natural endorphin supply

substance p

pain regulation/perception and immune response; abnormal oversupply can lead to chronic pain, inflammation

agonist

drugs that mimic neurotransmitters

antagonist

drugs that block neurotransmitters

reuptake

process where unused neurotransmitters are taken back up into the sending neuron (antidepressants block reuptake [reuptake inhibition] to treat depression)

psychoactive drugs

chemical substances that alter brain; causes changes in perceptions and moods by stimulating, inhibiting, or mimicking neurotransmitter activity

depressants

reduce neural activity, slow body functions (alcohol, opioids, barbiturates [tranquilizers])

opioids

opium and its derivatives; depress neural activity, temp lessening of pain and anxiety

barbiturates

depress CNS activity; reduce anxiety but impair memory and judgement

stimulants

excite neural activity, speed up body functions (caffeine, cocaine, nicotine, methamphetamines, ecstasy)

hallucinogens

psychedelic drugs; distort perceptions, evoke sensory images w/o sensory input; hallucinations and altered perceptions (marijuana, LSD/acid, ecstasy)

opioids

opium and its derivatives; depress neural activity; pain and anxiety relief by mimicking endorphins (agonist) (heroin, morphine, fentanyl)

tolerance

needing more of a drug to experience the desired effects

addiction

need to have the drug to avoid withdrawal symptoms

withdrawal

unpleasant mental or physical reactions when attempting to suddenly end drug use

multiple sclerosis

destruction of myelin sheath; disrupts APs, causing impaired mobility, paralysis, and pain

myasthenia gravis

blocked acetylcholine; disrupts APs, causing poor motor control and paralysis

blindsight

lesions to primary visual cortex let people “see” (catch a ball) despite being blind; evidence of association areas

prosopagnosia

face blindness caused by damage to occipital and/or temporal lobe

broca’s aphasia

damage to broca’s area; stuttered speech; intelligence is intact and understanding is present, but finding the words is difficult

wernicke’s aphasia

damage to wernicke’s area; jumbled speech; easy speech, but the meanings are odd (dont align with prompts)

phantom limb pain

pain from a limb that is no longer there (amputated); caused by brain plasticity

epilepsy

seizures related to too much glutamate (excitatory) and/or too little GABA (inhibitory). so, too much excitement/too little calming means seizures

alzheimer’s

destruction of acetylcholine in the hippocampus, causing memory loss

electroencephalogram (EEG)

shows broad brain activity (nonspecific) by observing brain’s electrical output with electrodes

functional magnetic resonance imaging (fMRI)

shows brain activity in specific regions by measuring oxygen via blood flow; shows brain function and structure

lesion

brain tissue destruction; may be natural from disease or trauma, may be from surgery, may be experimental by destroying with electrodes

hindbrain

medulla, pons, cerebellum; essential survival functions (breathing, sleeping, wakefulness, coordination, balance)

midbrain

atop brainstem; connects hindbrain with forebrain, controls some motor movement, transmits auditory and visual info

forebrain

cerebral cortex, thalamus, hypothalamus; complex cognitive activities, sensory and associative functions, voluntary motor activities

cerebellum

the “little brain”; processes sensory input, coordinates movement output and balance, enables nonverbal learning and memory. movement, balance, coordination, procedural memory

brainstem

central core of brain, beginning where the spinal cord swells as it enters the skull; responsible for automatic survival functions

medulla

base of the brainstem; controls heartbeat and breathing

reticular activating system

governs the reticular formation; controls alertness, arousal, sleep, eye movement

reticular formation

nerve network that travels through brainstem into the thalamus; filters info, significant in controlling arousal

basal ganglia

deep brain structures involved in motor movement

limbic system

neural system located mostly in the forebrain, below central hemispheres. includes amygdala, hypothalamus, hippocampus, thalamus, and pituitary gland; associated with emotions and drives

amygdala

two lima-bean-sized neural clusters in limbic system; linked to emotions and fear

hypothalamus

lies below thalamus; directs maintenance activities like eating, drinking, and body temperature; helps govern endocrine system and is linked to emotion and reward/pleasure

hippocampus

helps process explicit (conscious) memories (episodic and semantic memory; memory of events and facts) for storage

thalamus

forebrain’s sensory control center, on top of brainstem; directs messages to sensory receiving areas in cortex; transmits replies to cerebellum and medulla. relay center for all but smell

cerebrum

two cerebral hemispheres forming 85% of brain’s weight; enables perceiving, thinking, speaking

cerebral cortex

covers cerebrum; intricate, interconnected neural cells covering cerebrum; ultimate control and info-processing center

pituitary gland

comms w/ endocrine system and hypothalamus; releases hormones; master endocrine gland

frontal lobes

part of cerebral cortex just behind forehead; linguistic processing, muscle movements, higher-order thinking, executive functioning (making plans, judgements), personality, language

parietal lobes

part of cerebral cortex at top of head toward rear; receives sensory input for touch and body position

occipital lobes

part of cerebral cortex at back of head; includes areas that receive visual field info

temporal lobes

part of cerebral cortex above ears; auditory areas (each receives info primarily from opposite ear), enables language processing, hearing, face recognition

motor cortex

cerebral cortex area at rear of frontal lobes; controls voluntary skeletal movements; map of motor receptors

somatosensory cortex

cerebral cortex area at front of parietal lobes; registers, processes body touch and movement sensations; map of touch receptors

prefrontal cortex

front part of frontal lobes; enables judgement, planning, social interactions, processing of new memories; executive function

association areas

cerebral cortex areas that are not involved in primary motor or sensory functions; instead, involved in higher mental functions; learning, remembering, thinking, speaking. receives and integrates info from multiple areas and lobes

corpus callosum

large band of neural fibers connecting the two brain hemispheres and carrying messages between them. sometimes severed in those with severe seizures → split-brain patients

(neuro) plasticity

brain’s ability to reorganize, adapt throughout life in response to experiences, learning, and environmental changes. the brain can rewire to recover old/create new functions

aphasia

damaged speech from damage to left hemisphere association areas

broca’s area

left hemisphere frontal lobe; speech production, language processing, grammar formation, speech muscle coordination

broca’s aphasia

inability to produce fluent speech (broca → broken speech)

wernicke’s area

left hemisphere temporal lobe; language comprehension, understanding spoken and written language, interpreting words + sentences

wernicke’s aphasia

cant comprehend written or spoken language (wernicke’s → what?)

split-brain experiments

images shown to the R eye are processed in the L hemisphere - the patient can say what they saw (L hemisphere language). images shown to L eye are processed in R hemisphere - patient cannot say what they saw (could point with left hand)

endocrine system

body’s “slow” chemical communication system; set of glands and fat tissue that secrete hormones into the bloodstream throughout the body