Psychology: Sleep and Dreaming

Study Notes

Sleep and Dreaming

Altered State of Consciousness: A shift in the quality or pattern of mental activity. Influenced by various factors including drugs, medications, and sleep.
Circadian Rhythm: A 24-hour bodily rhythm that cycles through sleep and wakefulness.
Consciousness: A person's awareness of everything going on inside and outside themselves. It is essential for organizing behavior.
Dreams:
- According to Freud, they provide access to the unconscious mind, fulfilling wishes.
- Manifest Content: The actual content of the dream as described to others.
- Latent Content: The hidden meaning of the dream, which is believed to be significant.
Insomnia: Inability to fall asleep, stay asleep, or get good quality sleep.
- Commonly caused by stress, changes in lifestyle, and medical conditions.
- Researchers suggest cognitive behavior therapy as the most effective treatment.
Narcolepsy: A rare disorder where a person falls immediately into REM sleep during the day without warning.
- Diagnosed in approximately 1 in 2000 people.
- Characterized by sudden loss of muscle tone (cataplexy) triggered by emotional events.
- Primary treatment involves medication.
Nightmares: Bad dreams that arouse feelings of horror, helplessness, and extreme sorrow.
- Occur during REM sleep, typically in the second half of the night.
- Factors contributing to nightmares can include stress, trauma, and medications.
Non-REM Sleep: Non-rapid eye movement sleep stages (1-3) that are characterized by slower brain waves and reduced muscle activity.
REM Behavior Disorder: The mechanisms that typically block the movement of voluntary muscles during REM sleep fail, leading to physical activity and potentially acting out nightmares.
- Predominantly affects older males.
- Linked to Parkinson's disease.
- Diagnosed through sleep studies.
REM Sleep: Rapid eye movement sleep, often referred to as "active sleep."
- Characterized by rapid eye movements, dreaming, and muscle paralysis.
- The proportion of REM sleep decreases with age, being higher in younger individuals.
- The average sleep cycle is 90 minutes, with the first half of the night dominated by non-REM sleep and the second half by more REM sleep.
REM Paralysis: The inability of voluntary muscles to move during REM sleep.
Sleep Apnea: A condition where a person stops breathing for short periods during sleep.
- Classified as a sleep-related breathing disorder, often caused by a blocked airway.
- Symptoms include loud snoring and daytime sleepiness.
- Treatment includes Continuous Positive Airway Pressure (CPAP).
- It can have negative impacts on the cardiovascular system, increasing the risk of heart disease.
Sleep Need:
- Refers to the amount of sleep required by an individual to maintain optimal health and functioning.
- Sleep Deprivation: A significant loss of sleep, either acute or chronic.
- Consequences of Sleep Deprivation:
  - Behavioral: Increased risk-taking, alcohol consumption, smoking, and overeating.
  - Cognitive: Impairment in decision-making, focus, memory, planning, and problem-solving.
  - Emotional: Increased irritability, impatience, and emotional sensitivity.
  - Physical: Disrupted body weight regulation, increased risk of heart disease.
Sleep Stages:
- REM Sleep: Rapid eye movement sleep (active sleep)
- Non-REM Sleep: Non-rapid eye movement sleep (deep sleep, quiet sleep)
  - Stage 1: Light sleep characterized by hypnic jerks and hypnagogic images.
  - Stage 2: Temperature, breathing, and heart rate decrease during this stage. Sleep spindles are observed in brain activity.
  - Stage 3: The deepest sleep level, characterized by slow brain waves, decreased muscle activity, and the release of growth hormones. Difficult to wake someone up from this stage.
Sleep Terrors: Attacks of extreme fear that occur while the individual is sound asleep.
- The person does not wake up but may appear awake with a look of terror on their face.
- Occur during non-REM sleep, primarily in the first half of the night.
- Children typically do not remember them.
- They can be predicted based on consistent sleep schedules.
Sleepwalking: Occurs during deep non-REM sleep and involves movement or walking around in one's sleep.
- Most common in children.
- Primarily caused by sleep deprivation.
Theories of Sleep:
- Adaptive Theory: Animals and humans have evolved sleep patterns to avoid predators, sleeping when predators are most active.
- Restorative Theory: Sleep is necessary for the physical health of the body. (Recovery)
- Memory Consolidation Theory: Sleep plays a crucial role in transferring information from the hippocampus to the appropriate part of the cortex, solidifying memories.
- Creative Thinking/Problem Solving Theory: Sleep allows for the continuation of cognitive processes like problem-solving initiated during wakefulness.
- Growth/Development Theory: Hormones are released during sleep, regulating biological processes and playing a role in growth and development.