AP Psychology Unit 1 (Part 2)

Circadian Rhythm

The body’s biological clock; operates on a 24-hour cycle; regulates cycles of alertness and sleepiness

Ultradian Rhythm

90-minute sleep cycles; regulate sleep stages, oscillating between NREM and REM sleep; in consecutive cycles, N1 and N3 sleep shorten, while N2 and REM sleep lengthen.

Pre-NREM-1 Stage

Awake but relaxed; high frequency alpha waves

NREM Stage 1

characterized by theta brain waves; sensations from the environment filter into mental images/dreams; hypnagogic sensations—sensations of falling or floating and jerking awake

NREM Stage 2

Characterized by sleep spindles—rapid bursts of rhythmic brain wave activity; can be awakened w/o much difficulty, but clearly asleep

NREM Stage 3

Characterized by delta brain waves; deepest level of NREM sleep—lowest level of consciousness; tissue and cellular repair, strengthens immune system, growth hormone released; night terrors, sleepwalking, and sleeptalking occur in this stage

REM Sleep

Brain waves become rapid and saw-toothed; breathing heart rate, brain activity all increase, but body is paralyzed; characterized by rapid eye movement; most vivid dreams occur in REM; aids memory consolidation and learning

Suprachiasmatic Nucleus (SCN)

Pair of cell clusters in the hypothalamus that regulate circadian rhythm; adjusts melatonin production in response to light

Melatonin

A hormone that helps with the timing of the circadian rhythm; helps humans fall asleep and stay asleep

Insomnia

Sleep disorder characterized by difficulty falling and staying asleep; causes fatigue and increased risk of depression, obesity, hypertension, etc.

Narcolepsy

Sleep disorder characterized by sudden sleep attacks; fall directly into REM sleep; disrupts daily activities

Sleep Apnea

Sleep disorder characterized by stopped breathing during sleep; disrupts sleep and causes sleep deprivation; leads fatigue and increased risk of depression and obesity

Psychoactive Drug

A chemical substance that alters the brain, causing changes in perceptions and moods

Tolerance

When the brain and body adapt to offset the effects of a substance; requires a higher dose to feel the same effect

Withdrawal

Physical and psychological symptoms that occur after stopping intake of a drug

Physical: pain, headaches, nausea, vomiting, etc.

Psychological: guilt, depression, anxiety, desire to escape reality/lower self-awarness

Addiction

Physical and/or psychological dependence on a substance, causing disruptions of normal life activities

Stimulants

Drugs that excite neural activity and speed up body functions; heart rate, respiration, and body temp increase (similar to fight or flight response)

Depressants

Drugs that reduce neural activity and slow body functions; heart rate, respiration, and body temp decreases (similar to rest and digest response)

Hallucinogens

Psychedelic (“mind-manifesting”) drugs that distort perceptions and evoke sensory images in the absence of sensory input

Ecstasy (MDMA)

Stimulant and mild hallucinogen; causes serotonin transporters to pump serotonin into synapse, causing excess serotonin

Desirable effects: high energy, emotional elevation, connectedness with others

Negative effects: dehydration, permanently depressed mood (damage to serotonin-producing neurons), impaired cognitive and immune system functioning

Methamphetamine

Stimulant; causes dopamine transporters to pump dopamine into synapse, causing excess dopamine

Desirable effects: increased alertness and energy, euphoria

Negative effects: irritability, insomnia, hypertension, seizures

Cocaine

Stimulant; blocks reuptake, causing excess dopamine in the synapse

Desirable effects: rush of euphoria, increased energy and alertness

Negative effects: heightened reaction and aggression, cardiovascular stress, fidgeting, depressive crash

Alcohol

Depressant; increases the inhibitory effects of GABA and binds to glutamate receptors, preventing glutamate from binding

Desirable effects: rush of euphoria, disinhibition, relaxation, reduced self-consciousness

Negative effects: impaired decision making and motor function, slowed reactions, organ damage, impairs memory

Barbiturates

Depressants/tranquilizers; enhance the effects of GABA

Desirable effects: induce sleep, reduce anxiety

Negative effects: impairs memory and judgement

Opioids (e.g. Heroin)

Depressant; binds to opiate receptors, shutting down the release of inhibitory neurotransmitters and causing a flood of dopamine

Desirable effects: rush of euphoria, pain relief, stress relief

Negative effects: sedation, loss of natural endorphin production

Marijuana

Hallucinogen and mild depressant; binds to cannabinoid receptors, turning off the release of inhibitory neurotransmitters, causing a flood of dopamine

Desirable effects: disinhibition, relaxation, enhanced sensation, mild hallucinations

Negative effects: impaired learning and memory, impaired motor coordination and reaction time

LSD

Hallucinogen; mimics serotonin and binds to serotonin receptors; can be inhibitory or excitatory

Desirable effects: hallucinations

Negative effects: near-death experiences, panic