consciousness
our awareness of ourselves and our environment
cognitive neuroscience
the interdisciplinary study of brain activity linked with cognition
dual processing
the principle that information is often simultaneously processed on separate conscious and unconscious tracks
visual perception track
to recognize things and to plan future actions
visual action track
guides our moment-to-moment actions
cocktail party effect
ability to attend to only one voice among many
selective attention
the focusing of conscious awareness on a particular stimulus
change deafness
failing to notice changes in voices
inattentional blindness
failing to see visible objects when our attention is directed elsewhere
change blindness
failing to notice changes in the environment
choice blindness
failure to see a change made in one's choice
pop-out phenomenon
strong, distinct stimuli that catches our attention and demands to it
circadian rhythm
the biological clock; regular bodily rhythms that occur on a 24-hour cycle
REM sleep
rapid eye movement sleep, recurring sleep stage during which vivid dreams commonly occur
suprachaismatic nucleus
a pair of grain-of-rice-sized, 20,000-cell clusters in the hypothalamus; does its job by causing the brain's pineal gland to decrease the levels of melatonin in the morning or increase it in the evening
melatonin
sleep-inducing hormone
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
hypnagogic sensation
stage 1 of sleep, point between wakefulness and sleep; fantastic and vivid images felt
sleep spindles
bursts of rapid, rhythmic brain-wave activity
sleeeptalking
can occur during stage 2 or any other sleep stage; usually garbled or nonsensical
sleepwalking
end of deep sleep of stage 4; acting out one's dreams by rising out of bed
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
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 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
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
a compulsive drug craving and use, despite adverse consequences
depressants
drugs that reduce neural activity and slow body functions
barbiturates
(AKA tranquilizers) drugs that depress the central nervous system and its activity, reducing anxiety but impairing memory
opiates
opium and its derivatives, they depress neural activity, temporarily lessening 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
meth
a powerfully addictive drug that stimulates the CNS, 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
hallucinogens
psychedelic drugs, such as LSD, that distort perceptions and evoke sensory images in the absence of sensory input
LSD
a powerful hallucinogenic drug; also known as acid
THC
a major active ingredient in marijuana; triggers a variety of effects, including mild hallucinogens
near-death experience
an altered state of consciousness reported after a close brush with death