Stages of Sleep Overview

Stages of Sleep

• Stage 1: Transitional phase between wakefulness and sleep; brief duration; low-amplitude, rapid brain waves; vivid imagery may occur, but no true dreaming.
• Stage 2: Deeper sleep than Stage 1; characterized by slower waves and sleep spindles; comprises about half of total sleep; awakening is more difficult.
• Stage 3: Defined by slow brain waves with greater variation in amplitude than Stage 2.
• Stage 4: Deepest sleep stage; minimal response to external stimuli; critical for restorative processes.
• REM Sleep: Accounts for 20% of sleep; increased physiological activity includes heart rate, blood pressure, and breathing; dreaming occurs; major muscle paralysis; REM deprivation leads to rebound in REM sleep duration.

Sleep Cycles

• First half of the night dominated by stages 3 and 4 (deep sleep); second half dominated by stages 1, 2, and REM sleep.
• Sleep requirements vary across the lifespan; generally decreases with age.

Sleep Disorders

• Insomnia: Difficulty falling or staying asleep; affects up to one-third of individuals; often situational; treated through stimulus control.
• Sleep Apnea: Breathing difficulties during sleep; affects about 20 million people; common in overweight, middle-aged men; may lead to severe sleep disruption and health risks.
• Nightmares: Vivid, frightening dreams occurring during REM sleep; experienced by nearly everyone; chronic nightmares may indicate underlying emotional issues.
• Night Terrors: Sudden awakenings during non-REM sleep; common in children; intense fear and confusion; treatment often involves waiting for age-related reduction.
• Narcolepsy: Characterized by excessive daytime sleepiness and uncontrolled sleep episodes; affects 1 in 1000 people; linked to reduced quality of life; treated with naps and stimulants.
• Sleeptalking & Sleepwalking: Occur during stage 4 sleep; more common in children; usually harmless; awareness of environment is minimal; treatment includes awakening before incidents or psychotherapy.

Tips for Better Sleep

• Engage in regular exercise, ideally in the afternoon.
• Maintain a consistent bedtime routine.
• Consider warm milk before bed to aid sleep.
• Avoid stimulants like alcohol and caffeine close to bedtime.
• Refrain from heavy meals before sleep.
• Limit bed time outside of sleep; avoid stressful thoughts before bed.

Dream Characteristics

• Dreams consist of sequences of vivid and colorful images, often with distorted space-time relationships.
• Commonly charged with emotion and can alternate between pleasurable and frightening experiences.
• Not everyone remembers their dreams; non-recallers may still dream as frequently as those who do.

Meditation

• A mental state achieved through techniques like controlled breathing, focus restriction, and eliminating external stimuli.
• Transcendental Meditation (TM) is a commercial adaptation of traditional Yoga meditation practices.
• Elements for effective meditation include a quiet environment, comfortable position, mental focus, and a passive attitude.
• Psychological effects include feelings of calm and well-being; physiological effects include changes in brain activity, decreased heart rate, and reduced oxygen consumption.
• Utilized in clinical psychology to treat anxiety and stress-related disorders.