Unit 1 AP Psychology

Biological Bases of Behavior

neurons

a nerve cell - the fundamental unit of the brain and nervous system

multiple sclerosis

a chronic, often disabling disease that impacts the brain (when the immune system mistakenly attacks the myelin sheath)

neural transmission

the process by which neurons communicate with other parts of the body through a chemical message called neurotransmitters

resting potential

the, stable, negatively charged state of a neuron when it is inactive (-70 mV)… the cell is ready but not firing yet

threshold

the amount of stimulus required to trigger a neural impulse

depolarization

the process during the action potential when the cell’s charge turns from negative to positive (since positive ions flood the membrane)

action potential

a brief electrical charge that travels down the axon of a neuron (the actual firing part of the process)

excitatory

a signal that makes the neuron more likely to fire an action potential

inhibitory

a signal that makes the neuron less likely to fire an action potential

dopamine

a neurotransmitter involved in the reward process, motivation, motor control, and executive function

a low or high amount of dopamine is associated with…

schizophrenia and/or Parkinson’s disease

glutamate

a type of neurotransmitter that is the primary exciter of neurons (excitatory), too much can create overstimulation in the brain, leading to seizures and headaches

GABA

a type of neurotransmitter that is the primary inhibitor of neurons (inhibitory), too much can lead to fatigue while too little can lead to tremors, insomnia, seizures, etc (after all it does help you relax)

endorphines

a neurotransmitter that controls pain and is linked to reward (think “morphine” when you see the word), creates runner’s high

substance P

a neurotransmitter involved in transmitting pain messages to the brain

acetylcholine (ACh)

involved in memory and learning (the two go hand in hand), and very randomly, muscle movement

what two diseases are linked to a problem with acetylcholine

1) Alzheimer’s: Linked to the deterioration of neurons that produce ACh

2) Myasthenia Gravis: A disease of severe muscle weakness linked to antibodies that BLOCK ACh receptor sites in the brain

sensory neurons (afferent)

neurons that transmit messages from the body to the brain and spinal cord

motor neurons (efferent)

carry messages from the brain to the body (make you move after thinking)

interneurons

neurons in the brain and spinal cord that communicate with other neurons in the brain and spinal cord (thus the word inter)

reflex arcs

a simple, automatic response to a sensory stimulus that skips sending a message to the brain and is processed in the spinal cord for speed (think knee jerk)

central nervous system

brain + spinal cord

peripheral nervous system

everything besides the brain + spinal cord

somatic

controls voluntary movements of skeletal muscles

autonomic

controls life-essential, unconscious actions like heart rate and breathing

what two systems are within the autonomic part of the nervous system

sympathetic and parasympathetic

sympathetic nervous system

arouses the body and mobilizes energy in stressful situations (fight or flight)

parasympathetic

calms the body down, conserves energy (rest and repair)

endocrine system

system of hormones that cause different responses in the body

epinephrine

a hormone that increases heart rate, blood pressure, etc (adrenaline)

leptin

a hormone secreted by fat cells that tell you you’re full

ghrelin

secreted by an empty stomach, tells the brain you’re hungry (grrr in ghrelin = equal growling stomach)

melatonin

a hormone secreted by the pineal gland that regulates the sleep cycle

oxytocin

the cuddle hormone that helps humans bond

lesioning

the destruction of part of the brain

electroencephalogram

helps scientists examine the brain by looking at electrical brain waves, good for sleep studies

functional MRI (fMRI)

shows areas of the brain AND brain activity, it does so by looking at blood flow

medulla

part of the hindbrain and located at the base of the brainstem, controls heartbeat and breathing

cerebellum

part of the hindbrain, controls sensory input and coordinates movement + balance, looks like a little brain

pons

part of the hindbrain, focuses on facial recognition

reticular formation

a nerve network that travels through the brainstem and the thalamus

thalamus

part of the forebrain, the brain’s sensory control center - directs messages to the sensory receiving areas of the cortex so you can see, touch, hear, etc (doesn’t control smell though)

hypothalamus

directs several life maintenance functions (eating, drinking, body temperature), and has the pituitary gland (the master gland that controls the endocrine system)

amygdala

two lima bean sized neural clusters in the forebrain (specifically the limbic system), governs emotion (particularly anger and fear)

hippocampus

a processing center for long term (explicit memories), but is NOT where long-term memories are ultimately stored, think of it like a librarian

brainstem

focused on the survival of the person and life-sustaining functions (includes medulla, pons, and midbrain), slightly different from the hindbrain because the hindbrain is separate from the midbrain, and also includes the cerebellum

limbic system

a donut shaped system associated with drive and emotions (contains the hypothalamus, amygdala, and hippocampus)

hemispheric organization

the brain is split into two hemispheres that have different purposes and parts

brain lateralization

the idea that the brain’s two hemispheres have different specialties

contralateral control/organization

lateralization "contradicts” or “crosses” over—in other words, one side of the brain controls the opposite side of the body

corpus callosum

the bridge that connects the two hemispheres (basically a large band of neurons that carries messages between the two sides)

split brain patients

patients who exhibit and prove brain lateralization because their corpus callosum has been severed (so the two sides of their brain can no longer communicate)

cerebral cortex

the outer skin of the brain that is divided into four lobes

temporal lobe (the “ears”)

• linguistic processing (the brain’s ability to process language)

• Wernicke’s Area: located in the left temporal lobe, involved in language comprehension

wernicke’s aphasia

when Wernicke’s Area is damaged, people speak fluent words that make no sense (word salad) and can’t comprehend the words of others

occipital lobes (the “eyes”)

located at the back of the head, includes areas that receive and process visual information

the parietal lobes (the “navigator”)

located on top of the temporal lobe near the rear of the brain

Includes:

• somatosensory cortex: area that registers and processes body touch and movement sensations

phantom limb syndrome

a condition where someone experiences pain or sensations in a limb that is no longer there (usually caused by mistakenly interpreted neural impulses by the somatosensory cortex)

frontal lobes (the “Executive”)

the front of the cerebral cortex that participates in conducting planning, muscle movements, and speech

prefrontal cortex

located in the very front of the frontal lobe, is the executive function of the brain and manages things like decision making, planning, impulse control, and personality

motor cortex

located at the rear of the frontal lobe, an area that controls voluntary movements

Broca’s Area

located in the frontal lobe and directs the muscle movements required to create coherent speech

Broca’s Aphasia

damage to the Broca’s Area that allows you to understand words but not be able to speak them

association areas

areas in the cerebral cortex not associated with primary motor or sensory understanding but rather higher mental functions like thinking, remembering, and speaking

priming

an implicit memory effect where seeing one stimulus influences you to respond more efficiently to another (for example, seeing the color yellow might make it faster for you to recognize the word banana)

consciousness

our subjective awareness of ourselves, others, and our environment

includes various states such as alertness, sleep, and altered states influenced by drugs and hypnosis

blindsight

a neurological condition where people with visual impairment can respond to stimuli in their “blind field”, despite not actively seeing that stimuli

reuptake

the process by which neurotransmitters are reabsorbed by their sending neuron

this recycles the chemicals and regulates signals

agonists

Direct: resemble neurotransmitters and bind to receptor sites in their place

Indirect: block the reuptake of neurotransmitters, skyrocketing their levels and increasing their effects

antagonists

molecules/chemicals that completely block the receptor sites of the dendrite, making it so neurotransmitters aren’t effective

psychoactive drugs

chemical substances that alter your psyche - your emotions, moods, perceptions, or consciousness by acting on your nervous system

tolerance

the diminishing of the effect of a drug taken in the same doses, requiring the user to take larger and larger amounts

withdrawal

the discomfort/distress that follows discontinuing a drug or behavior

what are the four major drug classifications

depressants, stimulants, opiates, hallucinogens

depressant

a drug that reduces neural activity and slows body functions

what is the classification of alcohol

depressant - lowers inhibitions, slows neural processing, and disrupts memory formation by repressing REM sleep

stimulants

drugs that excite neural activity and speed up body functions

the world’s most widely consumed psychoactive substance

caffeine

what classification is caffeine

stimulant - it increases alertness by blocking a neurotransmitter that makes you sleepy (adenosine)

what classification is cocaine

stimulant - powerful stimulant that blocks the reuptake of dopamine, norepinephrine and serotonin, spiking levels of alertness and euphoria

hallucinogens

drugs that evoke sensory images and distort perceptions in the absence of sensory input (hallucinations)

LSD

a powerful synthetic drug that causes a “trip” and evokes a sense of euphoria or panic

closely resembles a prototype of serotonin

what is the classification of marijuana

hallucinogen - marijuana is often classified as a mild one, it amplifies sensitivity to colors, sounds, and tastes

however it also has some depressant-like effects (like relaxation)

what is the classification of ecstasy

considered both a stimulant and mild hallucinogen - major impact is causing the release of serotonin and blocking its reuptake

opiates (narcotics)

mimic the body’s painkillers and suppress neural activity

what is the mechanism of opiates

agonists: they flood the brain and mimic endorphins, causing the brain to stop producing natural ones, which leads to agonizing withdrawal

what classification is heroin

opiate

circadian rhythm

the biological clock - regulates bodily rhythms like temperature and wakefulness on a 24-hour schedule

sleep onset

the period when we are falling asleep (in between wakefulness and sleep), periods of being drowsy while awake

alpha waves

the waves our brains produce when we are drowsy yet awake

NREM 1

the transition from wakefulness to sleep, characterized by theta waves (high frequency, low amplitude waves)

NREM 2

the stage of sleep where you spend the most time

characterized by theta waves and sleep spindles (short bursts of rapid brain waves)

NREM 3

deep sleep or slow wave sleep, characterized by slow, large “delta” waves

this stage of sleep is difficult to wake from and is when the body repairs itself

NREM 4

also a stage of deep sleep characterized by delta waves (slow waves = slow, low frequency)

what is a way to encourage an increase in NREM 3 and 4

exercise

what happens after NREM stage 3 and 4?

we start to reverse and go through stages NREM 2 and 1

REM sleep (paradoxical sleep)

the stage of sleep characterized by a paralyzed body (though sometimes with slightly twitching muscles) and rapid eye movement, also the stage where dreams are most likely to occur

known as paradoxical sleep because our brain waves appear as active and intense as when we are awake

REM rebound

what you experience after being deprived or REM sleep, longer periods of REM sleep than normal the next day after being deprived

how long does a stage of sleep last

90 to 120 minutes

insomnia

a sleep disorder that creates persistent problems of getting to sleep or staying asleep