States of consciousness make up about 5% of the CLEP Psychology exam. Consciousness is your awareness of yourself and your environment, and it runs along a spectrum from full alertness through drowsiness, sleep, and altered states.
Your sleep-wake cycle follows a circadian rhythm, a roughly 24-hour biological clock. Its conductor is the suprachiasmatic nucleus (SCN) in the hypothalamus, which reads incoming light through the eyes. When light dims, the SCN signals the pineal gland to release melatonin, which promotes sleepiness. Bright light at night (screens) suppresses melatonin and shifts the clock later.
Sleep is measured with an EEG. Brain waves change in a predictable order.
| Stage | EEG signature | What happens |
|---|---|---|
| Awake, alert | Beta waves | Full alertness |
| Relaxed, eyes closed | Alpha waves | Drowsy calm |
| NREM-1 | Theta waves | Lightest sleep; hypnic jerks, brief images |
| NREM-2 | Sleep spindles and K-complexes | True sleep; about half the night |
| NREM-3 | Large, slow delta waves | Deep sleep; hardest to wake; sleepwalking and night terrors; dominates the first half of the night |
| REM | Awake-like fast waves, darting eyes | Vivid dreams; major muscles paralyzed (atonia) |
A full sleep cycle lasts about 90 minutes and repeats four or five times. Early cycles are heavy on deep NREM-3; later cycles trade deep sleep for longer REM periods, so the most vivid dreams and most REM occur near morning. REM is called paradoxical sleep because the brain looks awake while the body is paralyzed.
Leading accounts of sleep: restoration (repairing the body and clearing metabolic waste) and memory consolidation (the brain replays and files the day's learning). This is why cutting sleep short before a test backfires.
Two dream theories to contrast: - Freud's wish-fulfillment theory: dreams are disguised unconscious wishes. The manifest content is the remembered storyline; the latent content is the hidden wish. Little modern support, but the manifest/latent terms are tested. - Hobson's activation-synthesis theory: during REM, random neural activity rises from the brainstem, and the higher brain synthesizes it into a story.
| Disorder | Signature |
|---|---|
| Insomnia | Persistent trouble falling or staying asleep (most common) |
| Narcolepsy | Sudden, uncontrollable sleep attacks, sometimes dropping straight into REM/atonia |
| Sleep apnea | Repeatedly stopping breathing, briefly waking to gasp, all night |
| Night terrors | High-arousal terror during NREM-3, early in the night, with no recall (mostly children) |
| Somnambulism (sleepwalking) | Also an NREM-3 event, early in the night; hard to wake, no memory |
Note the contrast: a nightmare is a frightening dream during REM, later in the night, and is remembered; a night terror is a deep-sleep arousal that is not.
Hypnosis is a state of heightened suggestibility and focused attention. It can reduce pain and influence behavior, but it does not grant special powers or reliably recover accurate memories.
A psychoactive drug alters perception, mood, or consciousness by changing neurotransmitter activity.
| Category | Effect | Examples |
|---|---|---|
| Depressants | Slow the central nervous system | Alcohol, barbiturates |
| Stimulants | Speed up the nervous system | Caffeine, nicotine, cocaine, amphetamines |
| Hallucinogens | Distort perception; sensory images without sensory input | LSD, marijuana |
| Opioids | Depress activity, act on the endorphin system, relieve pain | Heroin, morphine |
Alcohol is a depressant; the early "lively" feeling is disinhibition, not stimulation. Three concepts govern drug use: tolerance (needing more for the same effect), withdrawal (the unpleasant state on stopping), and dependence/addiction (compulsive use despite harm).
Q1 — B (light detected through the eyes). - Correct: The SCN sets the circadian clock using light input, then triggers melatonin release when light dims. - A) Blood glucose, C) muscle fatigue, D) adrenaline, and E) body temperature alone are not the SCN's input signal. - Fix rule: The body clock runs on light — the SCN reads it through the eyes.
Q2 — E (NREM-3). - Correct: Large, slow delta waves with deep grogginess define NREM-3 deep sleep. - A) REM shows awake-like fast waves. B) Alpha is a relaxed waking state. C) NREM-1 shows theta waves. D) NREM-2 shows spindles and K-complexes. - Fix rule: Delta waves + hardest to wake = deep NREM-3.
Q3 — A (awake-like brain, paralyzed body). - Correct: The paradox is an active, awake-looking brain paired with a paralyzed body. - B) Slowest waves describe NREM-3. C) REM dreams are the most remembered, not the least. D) REM recurs and lengthens across the night. E) REM sleepers are not the easiest to wake. - Fix rule: "Paradox" = awake-like brain in a paralyzed body.
Q4 — A (REM, concentrated in later cycles). - Correct: REM lengthens across the night and dominates the final cycles, so cutting sleep short costs mostly REM. - B) NREM-3 dominates the FIRST half, so it is largely preserved. C) Alpha is a waking state, not lost sleep. D) Spindles mark NREM-2, spread through the night. E) Circadian rhythm is a clock, not a sleep amount. - Fix rule: REM piles up in the last cycles — short sleep robs REM first.
Q5 — A (story woven from random neural activity). - Correct: Activation-synthesis says the higher brain synthesizes a story from random brainstem activation during REM. - B) is Freud's theory. C) and D) misstate the theory, which ties dreams to brain activity. E) is a problem-solving view, not activation-synthesis. - Fix rule: Activation-synthesis = the brain makes a story out of random neural noise (Hobson).
Q6 — C (manifest; latent). - Correct: The remembered storyline is the manifest content; the hidden wish a Freudian seeks is the latent content. - A) reverses the two. B) and D) are sleep-stage terms, not dream-content terms. E) primary/secondary refers to reinforcers, not dreams. - Fix rule: Manifest = the Movie you remember; latent = the lurking hidden wish.
Q7 — B (sleep apnea). - Correct: Repeatedly stopping breathing and gasping awake all night is the defining pattern of sleep apnea. - A) Narcolepsy is sudden sleep attacks. C) Insomnia is trouble falling or staying asleep without breathing stoppages. D) Night terrors are early-night arousals. E) Somnambulism is sleepwalking. - Fix rule: Stops breathing + gasps awake repeatedly = sleep apnea.
Q8 — B (narcolepsy). - Correct: Sudden, uncontrollable sleep attacks with muscle collapse (dropping into REM/atonia) are narcolepsy. - A) Sleep apnea involves breathing stoppages, not sudden collapse into sleep. C) Insomnia is difficulty sleeping. D) Night terrors occur during deep sleep at night. E) Sleepwalking is movement during NREM-3. - Fix rule: Sudden daytime sleep attack + muscle collapse = narcolepsy.
Q9 — E (slows central nervous system activity). - Correct: Depressants like alcohol slow CNS activity, producing slowed reactions and impaired coordination. - A) describes stimulants. B) describes hallucinogens. C) describes opioids. D) is the opposite of a depressant's effect. - Fix rule: Alcohol slows the CNS; the "lively" phase is disinhibition, not stimulation.
Q10 — D (flawed; heroin is an opioid). - Correct: LSD and marijuana are hallucinogens, but heroin is an opioid, so the grouping is wrong. - A) They do not all distort perception. B) Only opioids act on endorphin receptors. C) Hallucinogens are not depressants. E) None of these three primarily increase alertness (that is stimulants). - Fix rule: Heroin belongs with the opioids, not the hallucinogens.
Q11 — D (tolerance and withdrawal). - Correct: Needing larger doses for the same effect is tolerance; the aches, sweating, and craving on stopping are withdrawal. - A) reverses the order and mislabels the stopping symptoms. B), C), and E) name unrelated sleep, learning, or drug-onset concepts. - Fix rule: Dose creeps up = tolerance; bad symptoms on quitting = withdrawal.
Q12 — C (flawed; alcohol is a depressant, effect is disinhibition). - Correct: Alcohol is a depressant; the louder, more sociable behavior reflects lowered inhibitions, not stimulation. - A) Alcohol slows, not speeds, the nervous system. B) Stimulants are defined by CNS speed-up, not sociability. D) Alcohol is not a hallucinogen. E) The early feeling is not a true stimulant heart-rate effect. - Fix rule: Feeling lively after drinking = disinhibition; alcohol is still a depressant.
Q1 — B (light detected through the eyes). - Correct: The SCN sets the circadian clock using light input, then triggers melatonin release when light dims. - A) Blood glucose, C) muscle fatigue, D) adrenaline, and E) body temperature alone are not the SCN's input signal. - Fix rule: The body clock runs on light — the SCN reads it through the eyes.
Q2 — E (NREM-3). - Correct: Large, slow delta waves with deep grogginess define NREM-3 deep sleep. - A) REM shows awake-like fast waves. B) Alpha is a relaxed waking state. C) NREM-1 shows theta waves. D) NREM-2 shows spindles and K-complexes. - Fix rule: Delta waves + hardest to wake = deep NREM-3.
Q3 — A (awake-like brain, paralyzed body). - Correct: The paradox is an active, awake-looking brain paired with a paralyzed body. - B) Slowest waves describe NREM-3. C) REM dreams are the most remembered, not the least. D) REM recurs and lengthens across the night. E) REM sleepers are not the easiest to wake. - Fix rule: "Paradox" = awake-like brain in a paralyzed body.
Q4 — A (REM, concentrated in later cycles). - Correct: REM lengthens across the night and dominates the final cycles, so cutting sleep short costs mostly REM. - B) NREM-3 dominates the FIRST half, so it is largely preserved. C) Alpha is a waking state, not lost sleep. D) Spindles mark NREM-2, spread through the night. E) Circadian rhythm is a clock, not a sleep amount. - Fix rule: REM piles up in the last cycles — short sleep robs REM first.
Q5 — A (story woven from random neural activity). - Correct: Activation-synthesis says the higher brain synthesizes a story from random brainstem activation during REM. - B) is Freud's theory. C) and D) misstate the theory, which ties dreams to brain activity. E) is a problem-solving view, not activation-synthesis. - Fix rule: Activation-synthesis = the brain makes a story out of random neural noise (Hobson).
Q6 — C (manifest; latent). - Correct: The remembered storyline is the manifest content; the hidden wish a Freudian seeks is the latent content. - A) reverses the two. B) and D) are sleep-stage terms, not dream-content terms. E) primary/secondary refers to reinforcers, not dreams. - Fix rule: Manifest = the Movie you remember; latent = the lurking hidden wish.
Q7 — B (sleep apnea). - Correct: Repeatedly stopping breathing and gasping awake all night is the defining pattern of sleep apnea. - A) Narcolepsy is sudden sleep attacks. C) Insomnia is trouble falling or staying asleep without breathing stoppages. D) Night terrors are early-night arousals. E) Somnambulism is sleepwalking. - Fix rule: Stops breathing + gasps awake repeatedly = sleep apnea.
Q8 — B (narcolepsy). - Correct: Sudden, uncontrollable sleep attacks with muscle collapse (dropping into REM/atonia) are narcolepsy. - A) Sleep apnea involves breathing stoppages, not sudden collapse into sleep. C) Insomnia is difficulty sleeping. D) Night terrors occur during deep sleep at night. E) Sleepwalking is movement during NREM-3. - Fix rule: Sudden daytime sleep attack + muscle collapse = narcolepsy.
Q9 — E (slows central nervous system activity). - Correct: Depressants like alcohol slow CNS activity, producing slowed reactions and impaired coordination. - A) describes stimulants. B) describes hallucinogens. C) describes opioids. D) is the opposite of a depressant's effect. - Fix rule: Alcohol slows the CNS; the "lively" phase is disinhibition, not stimulation.
Q10 — D (flawed; heroin is an opioid). - Correct: LSD and marijuana are hallucinogens, but heroin is an opioid, so the grouping is wrong. - A) They do not all distort perception. B) Only opioids act on endorphin receptors. C) Hallucinogens are not depressants. E) None of these three primarily increase alertness (that is stimulants). - Fix rule: Heroin belongs with the opioids, not the hallucinogens.
Q11 — D (tolerance and withdrawal). - Correct: Needing larger doses for the same effect is tolerance; the aches, sweating, and craving on stopping are withdrawal. - A) reverses the order and mislabels the stopping symptoms. B), C), and E) name unrelated sleep, learning, or drug-onset concepts. - Fix rule: Dose creeps up = tolerance; bad symptoms on quitting = withdrawal.
Q12 — C (flawed; alcohol is a depressant, effect is disinhibition). - Correct: Alcohol is a depressant; the louder, more sociable behavior reflects lowered inhibitions, not stimulation. - A) Alcohol slows, not speeds, the nervous system. B) Stimulants are defined by CNS speed-up, not sociability. D) Alcohol is not a hallucinogen. E) The early feeling is not a true stimulant heart-rate effect. - Fix rule: Feeling lively after drinking = disinhibition; alcohol is still a depressant.