Psychology of Sleep and Consciousness

Consciousness During Sleep

• People often incorrectly believe the brain shuts down during sleep. Many brain regions are actually more active during sleep than wakefulness.

Circadian Rhythms

• Circadian rhythms regulate biological cycles (physical, mental, and behavioral) in a 24-hour cycle.
• These rhythms are affected by light and darkness through a small area in the brain that controls them.

Stages of Sleep

Stage N1 Sleep

• Light sleep.
• Short duration (less than 10 minutes)
• Occurs immediately after falling asleep.

Stage N2 Sleep

• Easily awakened.
• 30-60 minutes in duration.
• Represents 45-55% of total sleep time.

Stage N3 Sleep

• Deep sleep; hard to wake
• Characterized by large, regular delta waves.
• Muscles, pulse and breathing rate slow down during this stage.

Stage R (REM) Sleep

• Rapid eye movement, dreaming, paralysis of motor system.
• Occurs approximately 90 minutes after falling asleep.
• Brain activity is high (beta wave activity).
• A person cycles through REM(and other stages) of sleep about five times throughout a typical night

Dreaming During Sleep

• Dreams are products of consciousness, where images and fantasies are confused with reality.
• People spend an average of 6 years dreaming in their lives.
• REM dreams are often bizarre, more elaborate, vivid, hallucinogenic, and emotional.
• Non-REM dreams typically feel more normal and less vivid compared to REM dreams

Sleep Disorders

Insomnia

• A repeated inability to sleep.
• Affects 10-30% of adults.
• More common in women and older adults
• Cognitive Behavioral Therapy (CBT) is an effective approach to managing insomnia.

Sleep Apnea

• Breathing stops because the throat closes, causing frequent awakenings during the night.

Narcolepsy

• Characterized by excessive sleepiness during waking hours; sometimes accompanied by sudden muscle weakness (going limp).

Altered States of Consciousness

Hypnosis

• Trance-like state.
• A social interaction in which a person is more susceptible to suggestion, affecting memory, perception and voluntary actions.
• Two theories of hypnosis exist:
  • Sociocognitive theory: Behaving as expected by others in such a state
  • Dissociation theory: People in an altered state of consciousness.

Meditation

• Intense contemplation leads to calmness, considered an altered state of consciousness
  • Concentrative Meditation: Focusing on an object or mantra
  • Mindfulness Meditation: Paying attention to the present moment without judgment.
  • Transcendental Meditation (TM): silently repeating a personal mantra for 15-20 minutes twice a day.

Psychoactive Drugs and the Brain

• Psychoactive drugs alter neurochemical systems, and can have both legitimate medical use and abuse potential.
• Drugs can affect many mental and physical processes, for example
  • Stimulants: Increase nervous system activity, (e.g. affect dopamine reuptake).
  • Depressants: Decrease nervous system activity
  • Opiates: Reduce pain and produce pleasurable feelings
  • Hallucinogens: Alter sensation and perception

Specific Examples of Psychoactive Drugs:

• Methamphetamine (meth): Blocks dopamine reuptake, damaging frontal lobes.
• Depressants: Decrease nervous system activity and can be sedatives. Alcohol is the most common depressant.
• Opiates: Reduce pain and cause feelings of relaxation.
• Hallucinogens: Alter sensation and perception; include MDMA (ecstasy), LSD, mushrooms, marijuana.