drugs (such as alcohol, barbiturates, and opiates) that reduce neural activity and slow body functions.
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.
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.
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.
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.
a physiological need for a drug, marked by unpleasant withdrawal symptoms when the drug is discontinued.
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.
the tendency for REM sleep to increase following REM sleep deprivation (created by repeated awakenings during REM sleep).
periodic, natural, reversible loss of consciousness—as distinct from unconsciousness resulting from a coma, general anesthesia, or hibernation. (Adapted from Dement, 1999.)
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.