Sleep Quiz

circadian rhythm

A physiological cycle of about 24 hours that is present in all eukaryotic organisms and that persists even in the absence of external cues.

Narcolepsy

A sleep disorder characterized by uncontrollable sleep attacks. The sufferer may lapse directly into REM sleep, often at inopportune times.

insomnia

Difficulty in falling asleep or staying asleep

sleep stages

Levels of sleep identified by brain-wave patterns and behavioral changes

NREM sleep

Quiet, typically dreamless sleep in which rapid eye movements are absent; divided into four stages; also called quiet sleep.

REM sleep

Rapid eye movement sleep, a recurring sleep stage during which vivid dreams commonly occur. Also known as paradoxical sleep, because the muscles are relaxed (except for minor twitches) but other body systems are active.

K complex

Single but large high-voltage spike of brain activity that characterizes stage 2 NREM sleep.

restoration theory of sleep

The body wears out during the day, and thus, sleep is necessary to put it back into shape.

Dreams

a sequence of images, emotions, and thoughts passing through a sleeping person's mind

night terrors

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

sleep apnea

a sleep disorder characterized by temporary cessations of breathing during sleep and repeated momentary awakenings

Dissociation

a split in consciousness, which allows some thoughts and behaviors to occur simultaneously with others

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

manifest content

according to Freud, the remembered story line of a dream

latent content

according to Freud, the underlying meaning of a dream

sleep deprivation

any significant loss of sleep, resulting in problems in concentration and irritability

Hallucinations

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

consciousness

our awareness of ourselves and our environment

sleep spindles

short bursts of brain waves detected in stage 2 sleep

Hypnosis

state of consciousness in which the person is especially susceptible to suggestion

delta waves

the large, slow brain waves associated with deep sleep

alpha waves

the relatively slow brain waves of a relaxed, awake state

REM rebound

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

adaptive theory of sleep

theory that organisms sleep for the purposes of self-preservation, to keep away from predators that are more active at night

function of dreams

to satisfy our own wishes, to file away memories, to develop and preserve neural pathways, to make sense of neural static, to reflect cognitive development