Sleep and Consciousness

Flashcards covering key vocabulary related to sleep, consciousness, and psychoactive drugs.

Consciousness

Awareness of our self and environment, with varying levels of awareness.

Alertness

A state of being awake, aware of one’s identity and surroundings, focusing attention.

Daydreaming

A relaxed state of mind with less focus than alertness; can also be light meditation.

Drowsiness

A state just before falling asleep or right after waking up, can be self-induced.

Electroencephalogram (EEG)

A measurement of electrical activity and brainwaves.

Beta Waves

Brainwaves associated with alertness and concentration, oscillating at 12-30 Hz.

Alpha Waves

Brainwaves associated with daydreaming, oscillating at 8-13 Hz.

Theta Waves

Brainwaves associated with drowsiness and light sleep, oscillating at 4-7 Hz.

Delta Waves

Brainwaves associated with deep sleep or coma, oscillating at 0.5-3 Hz.

Circadian Rhythms

Regular 24-hour body rhythms controlled by melatonin, affecting sleep cycles.

REM Sleep

Rapid eye movement sleep associated with dreaming, where the body is paralyzed.

Hypnagogic Hallucinations

Strange sensations or perceptions occurring while falling asleep.

Sleep Spindles

Bursts of rapid brain activity occurring during N2 sleep.

K-Complexes

Brain waves that suppress cortical arousal and aid in sleep-based memory consolidation.

Insomnia

Persistent trouble falling asleep or staying asleep.

Narcolepsy

A sleep disorder characterized by uncontrollable sleep attacks and REM sleep occurrences.

Sleep Apnea

A disorder where a person stops breathing during sleep, often leading to fatigue.

Hypnosis

An induced state of consciousness where a person is more susceptible to suggestion.

Meditation

A practice of self-regulating attention and awareness, often associated with relaxation.

Psychoactive Drugs

Substances that can alter consciousness and perceptions.

Depressants

Drugs that lower basic functions and neural activity, such as alcohol and benzodiazepines.

Stimulants

Drugs that excite the central nervous system, increasing heart rate and alertness.

Hallucinogens

Drugs that cause altered perceptions or hallucinations.

Opiates

Natural substances derived from opium that relieve pain.

Addiction

A physiological and psychological dependence on a substance.

N1 Sleep

The transitional phase between wakefulness and sleep (Stage 1), characterized by theta waves and hypnagogic hallucinations.

N2 Sleep

A stage of non-REM sleep (Stage 2) where it is harder to awaken someone; consists of more theta waves along with sleep spindles and K-complexes.

N3 Sleep

Also known as slow-wave sleep (Stage 3), characterized by delta waves (0.5-3 Hz). This is when sleepwalking and bed-wetting typically occur.

Activation-Synthesis Hypothesis

A theory suggesting that dreams are the brain's attempt to make sense of random neural activity occurring in the brainstem during REM sleep.

Reward Pathway

The mesolimbic pathway in the brain, primarily involving dopamine release from the ventral tegmental area (VTA) to the nucleus accumbens, which mediates addiction.

Tolerance

A phenomenon where the brain and body adjust to drug use, requiring higher doses of the substance to achieve the same initial effect.

Withdrawal

The cluster of physical and psychological symptoms that occur when a person stops using a drug they have become dependent on.

Barbiturates

A type of depressant (tranquilizer) used to induce sleep or reduce anxiety, though often replaced by benzodiazepines due to high toxicity and overdose risk.

Benzodiazepines

Depressants that enhance the brain's response to GABA, used to treat insomnia and anxiety by opening chloride channels to resistant excitation.

Melatonin

A hormone produced by the pineal gland that helps regulate the body's circadian rhythm and signals the body that it is time to sleep.