consciousness
our awareness of ourselves and our environment
selective attention
the focusing of conscious awareness on a particulus stimulus
circadian rhythm
the biological clock; regular bodily rhythms that occur on a 24-hour cycle
REM sleep
rapid eye movement sleep, a recurring sleep stage during which vivid dreams commonly occur
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 consequent momentary reawakenings
night terrors
a sleep disorder characterized by high arousal and an appearance of being terrified
dream
a sequence of images, emotions, and thoughts passing through a sleeping person's mind
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 amnesia
supposed inability to recall what one experienced during hypnosis
posthypnotic suggestion
a suggestion, made during a hypnosis session, to be carried out after the subject is no longer hypnotized
dissociation
a split in consciousness which allows some thoughts and behaviors to occur simultaneously with others
hidden observer
Hilgard's term describing a hypnotized subject's awareness of experiences, that go unreported during hypnosis
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
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 releive negative emotions
depressants
drugs that reduce neural activity and slow body functions
barbiturates
drugs that depress the activity of the CNS
opiates
opium and its derivates, which depress neural activity
stimulants
drugs that excite neural activity and speed up body functions
amphetamines
drugs that stimulate neural activity, cuaisng speeded-up body functions and associated energy and mood changes
ecstasy
a synthetic stimulant and mild hallucinogen; produces euphoria and social intimacy
hallucinogens
psychedelic drugs, such as LSD, that distort perceptions and evoke sensory images in the absence of sensory input
LSD
a powerful hallucinogenic drug
near-death experience
an altered state of consciousness reported after a close brush with death
THC
the major active ingredient in marijuana