Consciousness
our subjective awareness of ourselves and our environment
Hypnosis
a social interaction in which one person suggests to another that certain perceptions, feelings, thoughts, or behaviors will spontaneously occur
Selective Attention
focusing conscious awareness on a particular stimulus
Cocktail Party Effect
the ability to focus on one stimulus while filtering out a range of other stimuli
Inattentional Blindness
failing to see visible objects when our attention is directed elsewhere
Change Blindness
failing to notice changes in the environment
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
Parallel Processing
processing many 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 consciousnessâas distinct from unconsciousness resulting from a coma, general anesthesia, or hibernation
Circadian Rhythm
our 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; also known as paradoxical sleep, because the muscles are relaxed but other body systems are active
Alpha Waves
the relatively slow brain waves of a relaxed, awake state
Hallucinations
false sensory experiences
Delta Waves
the large, slow brain waves associated with deep sleep
Suprachiasmatic Nucleus (SCN)
a pair of cell clusters in the hypothalamus that controls circadian rhythm; in response to light, it causes the pineal gland to adjust melatonin production, thus modifying our feelings of sleepiness
Insomnia
recurring problems in falling or staying asleep
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 high arousal and an appearance of being terrified; occur during N3 sleep, within 2 or 3 hours of falling asleep, and are seldom remembered
Dream
a sequence of images, emotions, and thoughts passing through a sleeping personâs mind
Manifest Content
the symbolic, remembered story line of a dream
Latent Content
the underlying meaning of a dream
REM Rebound
the tendency for REM sleep to increase following REM sleep deprivation
Psychoactive Drugs
a chemical substance that alters perceptions and moods
Substance Use Disorder
a disorder characterized by continued substance craving and use despite significant life disruption and/or physical risk
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 drugâs effect
Addiction
an everyday term for compulsive substance use (and sometimes for dysfunctional behavior patterns) that continues despite harmful consequences
Withdrawal
the discomfort and distress that follow discontinuing an addictive drug or behavior
Depressants
drugs that reduce neural activity and slow body functions
Alcohol Use Disorder
alcohol use marked by tolerance, withdrawal, and a drive to continue problematic use
Barbiturates
drugs that depress central nervous system activity, reducing anxiety but impairing memory and judgment
Opiates
opium and its derivatives, such as morphine and heroin; 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 accelerated body functions and associated energy and mood changes
Nicotine
a stimulating and highly addictive psychoactive drug in tobacco products
Cocaine
a powerful and addictive stimulant derived from the coca plant; produces temporarily increased alertness and euphoria
Methamphetamine
a powerfully addictive drug that stimulates the central nervous system, with accelerated body functions and associated energy and mood changes; over time, reduces 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 that distort perceptions and evoke sensory images in the absence of sensory input
Near-Death Experience
an altered state of consciousness reported after a close brush with death; often similar to drug-induced hallucinations
LSD
a powerful hallucinogenic drug; also known as acid
THC
the major active ingredient in marijuana; triggers a variety of effects, including mild hallucinations