Consciousness- our awareness of ourselves and our environment
Biological rhythms- periodic physiological fluctuations
Circadian rhythm- the biological clock; regular bodily rhythms (ex. temperature and
wakefulness) that occur on a 24-hour cycle
REM sleep- rapid eye movement sleep, a recurring sleep stage during which vivid dreams
Also known as paradoxical sleep, because the muscles are relaxed
(except for minor twitches) but other body systems are active.
Alpha waves- the relatively slow brain waves of a relaxed, awake state
Sleep- periodic, natural, reversible loss of consciousness- as distinct from
unconsciousness resulting from a coma, general anesthesia, or hibernation
Hallucinations- false sensory experiences, such as seeing something in the absence of an
external visual stimulus
Delta waves- the large, slow brain waves associated with deep sleep
Insomnia- recurring problems in falling or staying asleep
Narcolepsy- a sleep disorder characterized by uncontrollable sleep attacks.
may lapse directly into REM sleep, often in inopportune times.
Sleep apnea- a sleep disorder characterized by temporary cessations of breathing during
sleep and repeated momentary awakenings.
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
Dream- a sequence of images, emotions, and thoughts passing through a sleeping
Dreams are notable for their hallucinatory imagery, discontinuities, and
incongruities, and for the dreamer’s delusional acceptance of the content and later
difficulties remembering it.
Manifest content- according to Freud, the remembered story line of a dream (as distinct
from its latent, or hidden, content).
Latent content- according to Freud, the underlying meaning of a dream (as distinct from
its manifest content).
Freud believed that a dream’s latent content functions as a safety
REM rebound- the tendency for REM sleep to increase following REM sleep deprivation
(created by repeated awakenings during REM sleep).
Hypnosis- a social interaction in which one person (the hypnotist) suggests to another
(the subject) that certain perceptions, feelings, thoughts, or behaviors will spontaneously
Posthypnotic suggestion- a suggestions, 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
Dissociation- a split in consciousness, which allows some thoughts and behaviors to
occur simultaneously with others
Psychoactive drug- a chemical substance that alters perceptions and mood