Psych 2e Chapter 4

Consciousness

The state of being aware of oneself, one's thoughts, and the environment. It includes both external awareness (e.g., sights and sounds) and internal awareness (e.g., emotions, memories, and thoughts). Consciousness is an ongoing stream that varies in clarity and alertness.

Biological rhythms

Internal cycles of biological activity, such as the menstrual cycle or temperature fluctuations. These rhythms are regular and predictable patterns controlled by internal biological clocks and can be influenced by external factors.

Circadian rhythm

A 24-hour biological cycle, such as the sleep-wake cycle, that regulates physical, mental, and behavioral changes. It is influenced by light and controlled by the suprachiasmatic nucleus (SCN) in the hypothalamus.

Suprachiasmatic nucleus (SCN)

A tiny region in the hypothalamus that acts as the brain’s clock, regulating circadian rhythms including sleep and wakefulness. It receives input from the retina and adjusts the body’s internal clock based on environmental light.

Melatonin

A hormone released by the pineal gland that plays a role in regulating the sleep-wake cycle. Its production is stimulated by darkness and inhibited by light.

Sleep debt

The cumulative effect of not getting enough sleep, which can result in fatigue, irritability, decreased cognitive performance, and health problems. Recovering from sleep debt requires more than just one night of rest.

REM sleep (Rapid Eye Movement sleep)

A stage of sleep characterized by rapid movement of the eyes, vivid dreams, and muscle paralysis. Brain activity during REM resembles that of wakefulness. REM is important for memory consolidation and emotional processing.

Non-REM sleep (NREM)

All stages of sleep except REM. It includes Stage 1 (light sleep), Stage 2 (onset of true sleep), and Stages 3 and 4 (deep sleep or slow-wave sleep). NREM is important for physical restoration and immune function.

Stage 1 sleep

The transition from wakefulness to sleep. It involves a decrease in muscle tension and body temperature. Brain waves shift from alpha waves to slower theta waves. People in Stage 1 sleep are easily awakened.

Stage 2 sleep

A deeper stage of sleep marked by the appearance of sleep spindles (brief bursts of activity) and K-complexes on EEG recordings. This stage accounts for about 50% of total sleep time.

Stage 3 and Stage 4 sleep

Also known as slow-wave sleep (SWS), these are the deepest stages of NREM sleep. Characterized by delta waves, these stages are critical for physical restoration, immune function, and memory consolidation.

Sleep spindle

A burst of rapid, rhythmic brainwave activity that occurs during Stage 2 sleep. It is thought to play a role in memory consolidation and maintaining sleep integrity.

K-complex

A large wave that occurs during Stage 2 sleep in response to environmental stimuli. It may help suppress arousal and aid in memory consolidation.

Delta waves

Very slow brainwaves associated with deep sleep (Stages 3 and 4). They are important for restorative sleep and physical healing.

REM rebound

The tendency to enter REM sleep more quickly and spend more time in REM after being deprived of it. This suggests the importance of REM sleep for normal functioning.

Insomnia

A common sleep disorder characterized by difficulty falling asleep, staying asleep, or waking too early. It can be acute or chronic and is often related to stress, anxiety, or poor sleep habits.

Sleep apnea

A serious sleep disorder in which breathing repeatedly stops and starts during sleep. There are two main types: obstructive (airway blockage) and central (brain fails to send signals to muscles that control breathing).

Obstructive sleep apnea

The more common form of sleep apnea, caused by the relaxation of throat muscles that block the airway during sleep. It can lead to loud snoring, gasping, and fatigue.

Central sleep apnea

A less common form of sleep apnea that occurs when the brain fails to send proper signals to the muscles that control breathing.

Sudden Infant Death Syndrome (SIDS)

The unexplained death of an infant during sleep, usually under one year of age. Risk factors include sleeping on the stomach, soft bedding, and overheating.

Narcolepsy

A sleep disorder characterized by uncontrollable sleep attacks, sudden muscle weakness (cataplexy), and sometimes hallucinations. It involves dysfunction in the regulation of REM sleep.

Cataplexy

A symptom of narcolepsy where a person experiences sudden, brief losses of voluntary muscle tone, often triggered by strong emotions like laughter or anger.

Parasomnias

A group of sleep disorders that involve abnormal movements, behaviors, emotions, or perceptions. Examples include sleepwalking, night terrors, and REM behavior disorder.

REM Sleep Behavior Disorder (RBD)

A parasomnia where the normal paralysis of REM sleep is absent, allowing a person to act out their dreams, which can lead to injury.

Sleepwalking (Somnambulism)

A parasomnia occurring during deep NREM sleep, where a person walks or performs complex behaviors while not fully conscious. It is more common in children.

Night terrors

A parasomnia involving sudden arousal from deep sleep with intense fear, screaming, and rapid heartbeat. Unlike nightmares, the individual usually doesn’t remember the episode.

Restless Leg Syndrome (RLS)

A sleep disorder characterized by uncomfortable sensations in the legs and an uncontrollable urge to move them. Symptoms are worse at night and can disrupt sleep.

Psychoactive drug

A chemical substance that alters perception, mood, consciousness, cognition, or behavior by affecting the brain's neurotransmitter systems.

Substance use disorder

A condition defined by the DSM-5 as a pattern of substance use leading to significant impairment or distress. It includes symptoms like tolerance, withdrawal, and continued use despite problems.

Physical dependence

A condition in which the body has adapted to a drug, requiring more of it to achieve the same effect (tolerance) and causing withdrawal symptoms if use stops.

Psychological dependence

An emotional or mental compulsion to use a substance, often to relieve stress or anxiety, even if there is no physical addiction.

Tolerance

A condition in which increasing amounts of a substance are needed to achieve the same effect due to the body’s adaptation.

Withdrawal

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

Depressants

Drugs that reduce neural activity and slow body functions. Examples include alcohol, barbiturates, and benzodiazepines. They increase the activity of GABA, an inhibitory neurotransmitter.

Stimulants

Drugs that increase neural activity and speed up body functions. Includes cocaine, amphetamines, nicotine, and caffeine. Often increase dopamine and norepinephrine activity.

Opiates

Narcotic drugs derived from the opium poppy (e.g., heroin, morphine) that relieve pain and produce euphoria by acting on the brain’s endogenous opioid system.

Hallucinogens

Psychoactive drugs that alter sensory perception and cognition, often causing hallucinations. Examples include LSD, mescaline, and psilocybin. Many affect serotonin levels.

Hypnosis

A state of focused attention, increased suggestibility, and deep relaxation. It can be used for pain management, anxiety, and habit change, but its effectiveness varies among individuals.

Meditation

A practice where an individual uses techniques such as mindfulness or focused breathing to achieve a mentally clear and emotionally calm state. Associated with reduced stress and improved focus and well-being.

Waking consciousness

The normal state of clear, organized alertness and awareness of one’s thoughts, feelings, and surroundings. It involves focused attention and purposeful mental activity.

Altered state of consciousness

A condition significantly different from normal waking awareness. It may be produced through drugs, meditation, hypnosis, sleep, or fatigue, and involves shifts in perception, emotion, thought, or behavior.

Daydreaming

A spontaneous shift of attention away from the external world to internal thoughts, fantasies, and memories. It’s a mild form of altered consciousness that occurs when we're bored or relaxed.

Drug-induced state

A type of altered consciousness produced by the consumption of psychoactive substances, which can influence perception, mood, and behavior by acting on the nervous system.

Hypnotic state

A focused, trance-like altered state of consciousness involving heightened suggestibility, deep relaxation, and reduced awareness of external stimuli. It is not the same as sleep.

Meditative state

An altered state of consciousness achieved through focused attention or mindfulness. Often associated with reduced stress, enhanced awareness, and changes in brain wave activity.

Unconscious state

A state in which a person is not aware of their surroundings or cannot respond meaningfully to stimuli. Includes states like deep sleep, coma, or the effects of anesthesia.

Conscious awareness

Thoughts and perceptions you are actively aware of. The top layer of mental activity that includes immediate thoughts, experiences, and surroundings.

Preconscious

Information that is not currently in conscious awareness but can be brought to consciousness easily, such as memories or knowledge.

Unconscious mind

A concept from psychoanalytic theory referring to thoughts, memories, and desires not accessible to conscious awareness but still influencing behavior and emotions.

Stages of Change Model (Transtheoretical Model)

A psychological model developed by Prochaska and DiClemente that describes the steps individuals go through when changing behavior, especially in overcoming addiction. The stages include precontemplation, contemplation, preparation, action, maintenance, and sometimes termination or relapse.

Precontemplation

The first stage of change, in which the individual is not yet considering change. They may be unaware that their behavior is problematic or deny the need to change. There is no intention to take action in the foreseeable future (usually within 6 months).

Contemplation

The second stage, where the individual is aware there is a problem and is beginning to think about change. They weigh the pros and cons of their behavior but have not yet committed to action. Change is being considered within the next 6 months.

Preparation (Determination)

The third stage, in which the individual has decided to change and begins making small steps or plans toward action. They may start researching strategies or set a quit date. Intention to take action is typically within the next 30 days.

Action

The fourth stage, where the individual actively makes changes to their behavior, environment, or experiences. This stage involves sustained effort and commitment to changing the behavior. It typically lasts up to 6 months.

Maintenance

The fifth stage, where the individual works to sustain the behavior change and prevent relapse. Coping strategies are developed and implemented to maintain the new behavior long term. This stage can last from 6 months to 5 years.

Relapse

A return to earlier behavior after a period of improvement. Relapse is common in addiction recovery and is considered part of the process. Individuals can re-enter the cycle at any stage, often with new insight.

Termination (optional stage)

The final stage in which the individual no longer feels tempted to return to the old behavior. The new behavior is fully integrated into their lifestyle, and there is full confidence in maintaining it without fear of relapse.