Psychology Chapter on Consciousness and Sleep

Consciousness and Sleep

• Consciousness is the subjective awareness of our unique thoughts, feelings, sensations, and environment.
• Wakefulness is a state of consciousness characterized by high levels of physical activity and sensory awareness.
• Sleep is a state of consciousness characterized by lower levels of physical activity and sensory awareness.

Stages of Sleep

• Stage 1 of Non-Rapid Eye Movement (NREM) sleep is marked by relatively rapid, low-amplitude brain waves. This stage can be characterized by feeling like you are viewing photos but not dreaming.
• Stage 2 of NREM sleep is marked by K complexes, which are single large negative waves followed immediately by single large positive waves. It becomes increasingly difficult to awaken someone from sleep as this stage progresses.
• Stage 3 & 4 of NREM sleep are marked by slower brain waves with greater peaks and valleys in the wave pattern than in Stage 2 sleep. These stages are characterized by deep sleep and the least responsiveness to outside stimulation.
• REM sleep is characterized by rapid eye movements, increased heart rate, irregular breathing, and muscle paralysis. Dreams tend to be vivid and easily remembered during this stage.

The Nature of Sleep

• Sleep is a period for rest and relaxation.
• It is necessary for normal human functioning.
• Studies suggest that sleep conserves energy at night, reduces brain activity to allow neurons to repair themselves, and allows receptor cells to rest.
• Lack of sleep can lead to: feeling nervous, reduced reaction time, reduced creativity, lower academic performance, lower physical ability, and increased risk of accidents.

The Function and Meaning of Dreaming

• The unconscious wish fulfillment theory, proposed by Sigmund Freud, suggests that dreams represent unconscious wishes the dreamer wants to fulfill.
  • Manifest content refers to the true subjects and meaning of the dream.
  • Latent content reveals the underlying unconscious wishes represented in a dream.
• The dream for survival theory suggests that dreams reconsider and reprocess information relevant to daily survival, providing clues about everyday survival concerns.
• The activation synthesis theory suggests that the brain produces random electrical energy during REM sleep, resulting in the random activation of memories that are tied together in a logical storyline. The dream scenario is related to the dreamer's concerns.

Circadian Rhythms and Sleep Disorders

• Circadian rhythms are physical, mental, and behavioral changes that follow a daily cycle, primarily responding to light and darkness in an organism's environment. This is similar to a body clock.
• Insomnia is a sleep disorder marked by the inability to initiate and maintain sleep.
  • Acute insomnia lasts for one night to a few weeks, but for less than three months.
  • Chronic insomnia occurs at least three nights a week for three months or more.
• Night terrors involve sudden awakenings, most often during Stage 4 sleep. These awakenings are accompanied by extreme fear, panic, and strong physiological arousal. They are common in children between the ages of 3 and 8.
• Narcolepsy is a sleep disorder that causes uncontrollable sleepiness. The disorder is characterized by uncontrollable episodes of sudden sleep attacks.

Hypothalamic Regions Involved in Sleep

• There are specific regions in the hypothalamus that are involved in regulating sleep patterns. However, the text does not specify which regions or how they are involved.