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compulsive drug craving and use.

alpha waves

brain wave of awake relaxed person


drugs that increase energy and stimulate neural activity


drugs that reduce anxiety and depress central nervous system activity


Our awareness Of ourselves and our environment

delta waves

the large, slow brain waves associated with deep sleep.


drugs (such as alcohol, barbiturates, and opiates) that reduce neural activity and slow body functions.


a split between different levels of consciousness


a sequence of images, emotions, and thoughts passing through a sleeping person's mind. are notable for their hallucinatory imagery, discontinuities, and incongruities, and for the dreamer's delusional acceptance of the content and later difficulties remembering it.


a synthetic stimulant and mild hallucinogen. Produces euphoria and social intimacy, but with short-term health risks and longer-term harm to serotonin-producing neurons and to mood and cognition.


natural painkiller produced by the brain

Freud's theory

theory that dreaming reflects our erotic drives


false sensory experiences, such as seeing something in the absence of an external visual stimulus.


psychedelic ("mind-manifesting") drugs, such as LSD, that distort perceptions and evoke sensory images in the absence of sensory input.


a social interaction in which one person (the hypnotist) suggests to another (the subject) that certain perceptions, feelings, thoughts, or behaviors will spontaneously occur.


recurring problems in falling or staying asleep.

latent content

deeper meaning of dreams


a powerful hallucinogenic drug; also known as acid (lysergic acid diethylamide).

manifest content

surface meaning of dreams


early name for hypnosis


a powerfully addictive drug that stimulates the central nervous system, with speeded-up body functions and associated energy and mood changes; over time, appears to reduce baseline dopamine levels.


the presumption that mind and body are different aspects of the same thing.


disorder in which sleep attacks occur

night terrors

a sleep disorder characterized by high arousal and an appearance of being terrified; unlike nightmares, night terrors occur during Stage 4 sleep, within two or three hours of falling asleep, and are seldom remembered.


opium and its derivatives, such as morphine and heroin; they depress neural activity, temporarily lessening pain and anxiety.

physical dependence

a physiological need for a drug, marked by unpleasant withdrawal symptoms when the drug is discontinued.

posthypnotic suggestion

a suggestion, made during a hypnosis session, to be carried out after the subject is no longer hypnotized; used by some clinicians to help control undesired symptoms and behaviors.

psychoactive drug

a chemical substance that alters perceptions and mood.

psychological dependence

a psychological need to use a drug such as to relieve negative emotions.


sleep stage associated with dreaming

REM rebound

the tendency for REM sleep to increase following REM sleep deprivation (created by repeated awakenings during REM sleep).

REM sleep

stage of sleep associated with muscular relaxation


neurotransmitter that LSD resembles


periodic, natural, reversible loss of consciousness—as distinct from unconsciousness resulting from a coma, general anesthesia, or hibernation. (Adapted from Dement, 1999.)

sleep apnea

sleep disorder in which breathing stops

sleep spindle

brain-wave activity during Stage 2 sleep

Stages 3 and 4 sleep

stage of sleep associated with delta waves


drugs (such as caffeine, nicotine, and the more powerful amphetamines, cocaine, and Ecstasy) that excite neural activity and speed up body functions.


the major active ingredient in marijuana; triggers a variety of effects, including mild hallucinations.


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.


the discomfort and distress that follow discontinuing the use of an addictive drug.

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