Chapter 9

Consciousness

An individual’s awareness of their environment and themselves.

Conscious level

Information you are actively aware of and can control.

Nonconscious level

Information processed automatically without awareness.

Preconscious level

Information not currently conscious but can easily be brought into awareness.

Unconscious

Mental processes that occur without conscious awareness.

Hypnagogic sensations

False sensations and muscle jerks that occur during NREM stage 1.

NREM 1,2,3

Stages of non-REM sleep; stage 1 is light sleep, stage 2 includes sleep spindles, and stage 3 is deep sleep.

REM paradoxical sleep

Sleep stage where vivid dreaming occurs; brain is active but body is paralyzed.

EEG patterns for each stage

NREM 1–2 theta waves, NREM 3 delta waves, REM beta waves.

Insomnia

Inability to fall asleep or stay asleep.

Narcolepsy

Neurological disorder causing sudden uncontrollable sleep attacks.

Sleep apnea

Sleep disorder involving repeated interruptions in breathing during sleep.

Sudden infant death syndrome (SIDS)

Unexpected death of an infant under one year old, often related to sleep position.

Somnambulism

A sleep disorder involving walking or other activities while asleep.

Nightmares

Disturbing dreams associated with fear or anxiety.

Sleep terror disorder

Sudden episodes of intense fear during deep sleep with little memory afterward.

REM behavior disorder (RBD)

Disorder where individuals physically act out their dreams.

Circadian rhythm

The body’s natural 24-hour sleep-wake cycle regulated by light.

Jet lag

Disruption of circadian rhythms caused by traveling across time zones.

Consolidation theory (dreams)

The idea that dreams help strengthen and organize memories.

Why we sleep: memory consolidation and restoration

Sleep allows the brain to process information and restore physical and mental energy.

Activation synthesis theory (dreams)

Dreams result from the brain interpreting random neural activity during sleep.

Hypnosis

A state of heightened focus and suggestibility.

Meditation

A mental practice that trains attention and awareness to reduce stress.

Psychopharmacology

The study of how drugs affect the brain and behavior.

Psychoactive drugs

Substances that alter thinking, mood, or behavior.

Reuptake inhibitors

Drugs that increase neurotransmitter levels by blocking reabsorption.

Agonists

Substances that mimic neurotransmitters and activate receptors.

Antagonists

Substances that block neurotransmitter receptors.

Addiction/dependence

Physical or psychological reliance on a substance.

Withdrawal symptoms

Negative physical or psychological effects after stopping drug use.

Drug tolerance

Reduced response to a drug requiring higher doses for the same effect.

Depressant drugs

Drugs that slow down the central nervous system.

GHB

A depressant drug that causes sedation and memory loss.

Stimulant drugs

Drugs that increase central nervous system activity and alertness.

Amphetamines

Stimulants that increase dopamine, norepinephrine, and serotonin activity.

Opioids

Drugs that relieve pain and produce euphoria by acting on opioid receptors.

Hallucinogenic drugs

Drugs that alter perception and cause hallucinations.

LSD

A powerful hallucinogen that alters perception and sensory experiences.

THC

The psychoactive chemical in marijuana that affects mood and perception.