Learn: Psychology and Sleep: Key Concepts and Theories

Psychology

1st version: the description and explanation of states of consciousness 2nd version: the science of behavior

Cognition

mental processes

Consciousness

our subjective awareness of ourselves and our environment

States of consciousness

normal waking awareness and various altered states

Cognitive neuroscience

the interdisciplinary study of the brain activity linked with cognition

Dual processing

the principle that information is often simultaneously processed on separate conscious and unconscious tracks.

Blindsight

a condition in which a person can respond to a visual stimulus without consciously experiencing it.

visual perception track

enables us "to think about the world" — to recognize things and to plan future actions.

visual action track

guides our moment-to-moment movements.

Parallel processing

processing multiple aspects of a stimulus or problem simultaneously.

Sequential processing

processing one aspect of a stimulus or problem at a time; generally used to process new information or to solve difficult problems.

Sleep

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

Circadian rhythm

our biological clock; regular bodily rhythms (for example, of temperature and wakefulness) that occur on a 24-hour cycle.

Circa

about

Diem

day

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. (Sometimes called R sleep.)

Alpha waves

the relatively slow brain waves of a relaxed, awake state.

Stage 1

marked by the slowed breathing and the irregular brain waves

NREM sleep

non-rapid eye movement sleep; encompasses all sleep stages except for REM sleep.

(Stage 1) Hallucinations

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

(Stage 1) Hypnagonic sensations (hypnic sensations)

bizarre experiences, such as jerking or a feeling of falling or floating weightlessly, while transitioning to sleep.

(Stage 2) Sleep spindles

bursts of rapid, rhythmic brain-wave activity that aid memory processing

(Stage 3) Delta waves

the large, slow brain waves associated with deep sleep.

Sleep paralysis

immobility may occasionally linger as you awaken from REM sleep

Paradoxical sleep

The body is internally aroused, with waking-like brain activity, yet asleep and externally calm.

suprachiasmatic nucleus (SCN)

a pair of cell clusters in the hypothalamus that controls circadian rhythm. In response to light, the SCN adjusts melatonin production, thus modifying our feelings of sleepiness.

Melatonin

a sleep-inducing hormone found in the hypothalamus

desynchronization

become more likely to develop fatigue, stomach problems, heart disease, and, for women, breast cancer

Why sleep

protects, restores, aids memory consolidation, feeds creative thinking, growth, conserve energy

Free radicals

molecules that are toxic to neurons

Consolidated memories

during slow-wave deep sleep, by replaying recent learning and strengthening neural connections

Ghrelin

a hunger-arousing hormone

Leptin

hunger-suppressing hormone

Cortisol

a stress hormone that stimulates the body to make fat, and decreasing metabolic rate

Microsleep

1 to 6 secs of sleep

Insomnia

recurring problems in falling or staying asleep.

Narcolepsy

a sleep disorder characterized by uncontrollable sleep attacks. The affected person may lapse directly into REM sleep, often at inopportune times.

Sleep apnea

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

Somnambulism

sleepwalking

REM sleep behavior disorder

a sleep disorder in which normal REM paralysis does not occur; instead, twitching, talking, or even kicking or punching may occur, often acting out one's dream.

Dreams

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

The Interpretation of Dreams

dreams provide a psychic safety valve that discharges otherwise unacceptable feelings.

manifest content

the apparent and remembered story line) as a censored, symbolic version

Latent content

the unconscious drives and wishes (often erotic) that would be threatening if expressed directly.

Information processing

dreams help sift, sort, and fix (consolidate) the day's experiences in our memory.

Activation synthesis theory

dreams are the brain's attempt to synthesize random neural activity.

simulate reality

drawing on our concepts and knowledge. They engage brain networks that also are active during daydreaming

REM rebound

the tendency for REM sleep to increase following REM sleep deprivation.

Physiological function

Regular brain stimulation from REM sleep may help develop and preserve neural pathways.

Activation synthesis

REM sleep triggers neural activity that evokes random visual memories, which our sleeping brain weaves into stories.

Cognitive development

Dream content reflects dreamers' level of cognitive development — their knowledge and understanding. Dreams simulate our lives, including worst-case scenarios.

Basic principle

Biological and psychological explanations of behavior are partners, not competitors.