Consciousness, Sleep, Dreams, and Psychoactive Drugs

Flashcards covering key vocabulary terms related to consciousness, its properties, sleep stages and disorders, dream theories, and major categories of psychoactive drugs.

Consciousness

A state of awareness, often described as remarkable and complex, leading to subjective experience.

Intentionality (of Consciousness)

The quality of being directed towards an object; consciousness is always about something and is limited.

Unity (of Consciousness)

The resistance to division; the ability to integrate information from all the body's senses into one coherent whole.

Selectivity (of Consciousness)

The capacity to include some objects but not others, filtering out certain information.

Dichotic Listening

A task where people wearing headphones hear different messages in each ear and are asked to repeat aloud words from one ear, demonstrating consciousness's selective nature.

Cocktail-Party Phenomenon

The ability to tune into one message even while filtering out others nearby, and to notice personally relevant information (like one's name) in the filtered-out sound.

Transience (of Consciousness)

The tendency for the mind to wander and change, often referred to as the 'stream' of consciousness by William James.

Sleep Cycle

The regular cycle of sleep and waking, naturally occurring over approximately 24 hours.

Circadian Rhythm

A naturally occurring 24-hour cycle (from Latin 'circa dies' meaning 'about day') that regulates the sleep-wake cycle.

Beta Waves

High-frequency brain activity present during states of alertness and wakefulness.

Alpha Waves

Lower-frequency brain activity characteristic of a drowsy or relaxed state.

Theta Waves

Brain waves characteristic of Stage 1 and Stage 2 sleep.

Delta Waves

Slow, high-amplitude brain waves characteristic of the deepest stages of sleep (Stage 3 and Stage 4).

Sleep Spindles

Short bursts of brain activity that interrupt theta waves during Stage 2 sleep.

K-Complexes

Large, slow waves that occur occasionally during Stage 2 sleep, often in response to external stimuli.

REM Sleep

A stage of sleep characterized by rapid eye movements, high levels of brain activity (saw-tooth waves similar to beta waves), and vivid dreaming.

Electrooculograph (EOG)

An instrument used to measure eye movements, particularly to detect when a person is in REM sleep.

Memory Consolidation

The process by which memories become stable in the brain, which sleep, particularly following learning, appears to be essential for.

REM Rebound

An increased amount of REM sleep the night after a period of REM deprivation.

Insomnia

The most common sleep disorder, characterized by difficulty in falling asleep or staying asleep.

Sleep Apnea

A sleep disorder in which the person stops breathing for brief periods while asleep, most often occurring in middle-aged, overweight men.

Somnambulism

The act of rising and walking during sleep, more common in children; also known as sleepwalking.

Narcolepsy

A sleep disorder characterized by sudden and uncontrollable sleep attacks that occur in the middle of waking activities, often leading directly into REM sleep.

Sleep Paralysis

The experience of waking up unable to move, lasting from several seconds to several minutes.

Night Terrors

Abrupt awakenings with panic and intense emotional arousal, occurring most often in children.

Manifest Content (of Dreams)

According to Freud, a dream's apparent topic or superficial meaning.

Latent Content (of Dreams)

According to Freud, a dream's true underlying meaning, representing unconscious wishes.

Activation-Synthesis Model

The theory that dreams are produced when the brain attempts to make sense of random neural activity that occurs during sleep.

Depressants

Psychoactive substances that reduce the activity of the central nervous system, leading to calming or sedative effects, and at high doses, can induce sleep or arrest breathing.

Barbiturates

A type of depressant (e.g., Seconal, Nembutal) prescribed as sleep aids and anesthetics before surgery.

Benzodiazepines

A type of depressant (e.g., Valium, Xanax) also called 'minor tranquilizers,' prescribed as anti-anxiety drugs.

Toxic Inhalants

Depressant substances (e.g., glue, gasoline) that when 'sniffed' or 'huffed' produce temporary effects resembling drunkenness, with potential for lethal overdose and neurological damage.

Expectancy Theory (Alcohol)

The idea that alcohol's effects can be produced by people's expectations of how alcohol will influence them in particular situations.

Alcohol Myopia

A condition that results when alcohol hampers attention, leading people to respond in simple ways in complex situations.

Stimulants

Psychoactive substances (e.g., caffeine, nicotine, amphetamines, cocaine) that excite the central nervous system, heightening arousal and activity levels, and increasing dopamine and norepinephrine.

Narcotics (Opiates)

Highly addictive drugs (e.g., heroin, morphine, codeine) derived from opium that relieve pain and induce feelings of well-being and relaxation by mimicking the brain's endorphins.

Endorphins

Endogenous opioids produced by the brain that play a role in internal relaxation and stress relief, mimicked by narcotics.

Hallucinogens

Drugs (e.g., LSD, mescaline, psilocybin, PCP, ketamine) that alter sensation and perception and often cause visual and auditory hallucinations, generally not addictive.

Marijuana

The leaves and buds of the hemp plant containing THC, a psychoactive drug that produces a mildly hallucinogenic intoxication with minimal physical withdrawal symptoms.

Gateway Drug

A drug (like marijuana, for some) that is believed to increase the risk of the subsequent use of more harmful drugs.

Self-Knowledge (Consciousness Meaning)

The quality of an intelligent being having information about itself, reflecting on its own understanding or existence.

Access To Information (Consciousness Meaning)

The availability of information processing to systems underlying verbal reports, rational thought, and deliberate decision-making.

Sentience

Subjective experience, phenomenal awareness, or 'raw feels'; what it is like to be or do something, as defined by Thomas Nagel ('What Is It Like to Be a Bat?').

The Hard Problem (of Consciousness)

David Chalmers' term for the challenge of understanding why some physical processes in the brain have an experience associated with them at all, contrasted with 'easy problems' like explaining brain functions.