consciousness
our awareness of ourselves and our environment
biological rhythms
periodic physiological fluctuations
circadian rhythm
the biological clock; regular bodily rhythms
REM sleep
rapid eye movement sleep, a recurring sleep stage during which vivid dreams commonly occur (paradoxical sleep)
alpha waves
the relatively slow brain waves of a relaxed, awake state
sleep
periodic, natural, reversible loss of consciousness
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
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; occur during Stage 4 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. notable for their hallucinatory imagery, discontinuities, and incongruities
manifest content
according to Freud, the remembered story line of a dream
latent content
according to Freud, the underlying meaning of a dream
REM rebound
the tendency for REM sleep to increase following REM sleep deprivation
hypnosis
a social interaction in which one person suggests to another that certain perceptions, feelings, thoughts, or behaviors will spontaneously occur
posthypnotic suggestion
a suggestion, made during a hypnosis session, to be carried out after the subject is no longer hypnotized; used by some clinicins to help control undesired symptoms and behaviors
dissociation
a split in consiousness, which allows some thoughts and behaviors to occur simultaneously with others
psychoactive drug
a chemical substance that alters perceptions and mood
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
depressants
drugs (such as alcohol, babiturates, and opiates) that reduce neural 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 lessoning pain and anxiety
stimulants
drugs that excite neural activity and speed up body functions
amphetamines
drugs that stimulate neural activity, causing speeded-up body functions and associated energy and mood changes
methamphetamine
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
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
psychedelic drugs, such as LSD, that distort perceptions and evoke sensory images in the absense of sensory input
LSD
a powerful hallucinogenic drug (lysergic acid diethylamide)
THC
the major active ingredient in marijuana; triggers a variety of effects, including mild hallucinations
near-death experience
an altered state of consciousness reported after a close brush with death; often similar to drug-induced hallucinations
dualism
the presumption that mind and body are two distinct entities that interact
monism
the presumptions that mind and body are different aspects of the same thing