Psychology Chapter: Consciousness and Sleep Stages

Study Notes

Consciousness encompasses all awareness at a given moment, including thoughts, feelings, and external events.
It's also defined as awareness of oneself and the environment.
The brain constructs an alternative conscious world through various experiences:
- Spontaneously (e.g. daydreaming)
- Physiologically induced (e.g. hallucinations, orgasm, sensory deprivation)
- Psychologically induced (e.g. hypnosis, meditation)

Most adults need 7-10 hours of sleep.
Newborns need 16 hours a day.
Sleep progresses through stages based on brain wave patterns.
Mnemonic Acronym: Beta, Alpha, Theta, Delta
- Be (Beta): Awake
- Awake (Alpha): Relaxed, awake
- Then (Theta): Entering sleep
- Dreaming (Delta): Deep sleep
Stage 1: (10 minutes) Often unaware of sleeping, may experience a sensation of falling or sudden jerking.
Stage 2: (30 minutes) Characterized by sleep spindles and K-complexes, a decrease in heart rate and body temperature, and muscle relaxation. 65% of sleep is in this stage.
Stage 3 & 4: (30 minutes) Deep sleep, hard to awaken, important for muscle restoration and repair.
REM (Rapid Eye Movement): Characterized by quick eye movements, often associated with vivid dreaming (80-90% report dreams). This stage occurs in cycles throughout sleep.
REM sleep Stage #5: (20-25% of nighttime sleep) Vivid dreams occur.

The function of eye movements during REM sleep is unknown.
Individuals with REM Behavior Disorder lack the paralysis that normally occurs during REM and act out their dreams.
REM dreams are typically more emotional and illogical.
Non-REM dreams are thought-like and repetitive.
Lucid Dreaming: Aware of dreaming while sleeping.
Sleep anomalies:
- Somnambulism (sleepwalking) occurs during stages 3 and 4 sleep.
- Somniloquy (sleep talking) can occur in any stage, more often in children.
- Narcolepsy: Sleep disorder characterized by excessive daytime sleepiness and uncontrolled REM sleep.
- Sleep Apnea: Breathing stops during sleep, causing the person to briefly awaken.
- Insomnia: Difficulty falling or staying asleep.
- Night Terrors: Frightening dreams occurring in stages 3 and 4, usually within a short time of falling asleep.

Dream Function (Freud): Dreams represent wish fulfillment, often with sexual themes and less emphasis on accidental misfortunes.
Dreams may be important for processing memories, learning strategies, and problem-solving.
During REM sleep, acetycholine increases while serotonin and norepinephrine decrease.
Pons signals are incomplete, interpreted by the forebrain with the amygdala active.
Nightmares typically occur toward morning during REM sleep and are terrifying.