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consciousness

our awareness of ourselves and our environment

circadian rhythm

the biological clock; regular bodily rhythms that occur on a 24-hour cycle

REM sleep

rapid eye moment 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

alpha waves

the relatively slow brain waves of a relaxed, awake state

sleep

periodic, natural 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

NREM sleep

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

narcolepsy

a sleep disorder characterized by uncontrollable sleep attacks. The sufferer 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

night terrors

a sleep disorder characterized by a 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 person's mind. 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)

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 suggests to another that certain perceptions, feelings thoughts or behaviors will spontaneously occur

posthypnotic suggestions

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

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 moods

tolerance

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

withdrawal

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

physical dependence

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

psychological dependence

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

addiction

compulsive drug craving and use, despite adverse consequences

depressants

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

barbiturates

drugs that depress the activity of the central nervous system, reducing anxiety but impairing memory and judgment

opiates

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

stimulants

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

amphetamines

drugs that stimulate neural activity, causing sped-up body functions and associated energy and mood changes

methamphetamine

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

near-death experience

an altered state of consciousness reported after a close brush with death (such as cardiac arrest); often similar to drug-induced hallucinations

THC

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

homeostasis

a state of psychological equilibrium obtained when tension or a drive has been reduced or eliminated

insomnia

recurring problems in falling or staying asleep

activation-synthesis theory

theory that dreams reflect inputs from brain activation originating in the pons, which the forebrain then attempts to weave into a story

biofeedback

a training program in which a person is given information about physiological processes (heart rate or blood pressure) that is not normally available with the goal of gaining conscious control of them

meditation

the act of deep thinking or reflection

ecstasy (MDMA)

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

hallucinogens

psychedlic drugs, such as LSD, that distort perception and evoke sensory images in the absence of sensory input

LSD

a powerful hallucigenic drug; also known as acid

Stanley Coren

figured most humans will sleep 9 hours if uninterrupted

William Dement

Sleep researcher who discovered and coined the phrase "rapid eye movement" (REM) sleep.

Sigmund Freud

considered dreams the key to understanding our inner conflict

Ernest Hilgard

believed hypnosis invovles not only social influences but also a special state of dissociation

Albert Hofmann

a Swiss scientist known best for being the first person to synthesize, ingest and learn of the psychedelic effects of lysergic acid diethylamide (LSD).

Nicholas Spanos

hypnosis researcher

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