Sleep Disorders and Theories
Insomnia
- Definition: Insomnia is a sleep disorder characterized by:
- An inability to initiate and maintain sleep.
- Individuals may fall asleep but wake up a few hours later without the ability to resume sleeping for the remainder of the night.
- Prevalence:
- Affects approximately 10% of the general population.
- More common in women than men.
- Physiological Contributing Factors:
- Increased muscle tension in the head and neck muscles.
- Tension headaches.
- Gastric/stomach issues.
- Maladaptive Sleep Habits Contributing to Insomnia:
- Excessive daytime napping.
- Spending too much time in bed during the day, often linked to depression.
- Erratic sleep schedules such as shift work.
- Falling asleep to external stimuli like TV, music, or environmental factors (open windows or cold air).
Nightmares
- Definition: Nightmares refer to frightening dreams that:
- Are vivid and can be easily recalled.
- Occur during REM sleep, typically in the early morning hours.
- Triggers:
- Staying up too late.
- Eating heavy meals close to bedtime, especially those high in carbohydrates.
- Overexcitement prior to sleep, such as watching a scary movie.
- Prevalence: Nightmares are more common among girls than boys.
Sleep Disorders Overview
- General Information:
- Most individuals experience sleep issues from time to time.
- Transient sleep problems often arise from external stressors.
- Approximately 6% of the adult population seeks medical help for a sleep disorder.
- List of Sleep Disorders to Discuss:
- Somnambulism (Sleepwalking)
- Somniloquy (Sleep talking)
- Sleep Apnea
- Narcolepsy
- Insomnia
- Nightmares
- Sleep Terrors
- Sleep Paralysis
Somnambulism and Somniloquy
- Definitions:
- Somnambulism: Sleepwalking.
- Somniloquy: Sleep talking.
- Occurrence: Both disorders occur during stages 3 and 4 of sleep (deepest sleep) within the first third of the night.
- Characteristics:
- Individuals may have their eyes open, displaying a blank expression, but show no response.
- Individuals typically experience amnesia for the event upon waking.
- Important: Awakening a sleepwalker can lead to confusion and disorientation.
- Prevalence Among Children:
- Approximately 30% of children under age 6 have experienced sleepwalking or talking once.
- About 2-3% of children experience these episodes frequently.
- Some teenagers may outgrow sleepwalking/talking after puberty, while others do not.
- Genetic Patterns:
- Familial patterns reported in up to 80% of individuals with somnambulism.
- Often associated with sleep terrors.
Sleep Apnea
- Definition: Sleep apnea is a disorder characterized by:
- Repeated cessation of breathing during sleep.
- Frequency:
- Documented cases indicate individuals can stop and start breathing between 500 and 1000 times a night, with each episode lasting approximately 90 seconds.
- Prevalence:
- More common in men than in women (ratio 2:1).
- Particularly prevalent among morbidly obese individuals.
- Causes:
- Structural defects such as enlarged tonsils.
- Excess fat tissue around the neck.
- An overly thick palate.
Subconscious and Unconscious Processing
- Subconscious Processing:
- Involves memory that is not currently in consciousness but can be retrieved later through specific recall methods.
- Example: Forgetting someone's name and then recalling it later.
- Unconscious Processing:
- Refers to all processes and information that are not in consciousness.
- According to Psychodynamic Theory (Freud), it consists of processes that are kept out of consciousness to avoid anxiety and/or guilt.
- Such processes arise from the need to repress unpleasant memories or feelings.
The Nature of Sleep and Its Theories
- Common Form of Altered Consciousness:
- Sleep is regarded as the most common form of altered consciousness.
- Humans spend approximately 1/3 (33%) of their lives asleep.
- Theories Explaining the Need for Sleep:
- Preservation and Protection Theory of Sleep:
- Sleep forces individuals to be inactive during periods of greatest personal risk (to prevent injury or death) and when expending energy yields the least benefit.
- This perspective is evolutionary, suggesting sleep developed over time as a protective adaptation.
- Restorative Sleep Theory:
- Sleep enables the repair and revitalization of the body and mind.
- Sleep allows the brain to rest, consolidate memories, and facilitate clear cognitive functioning such as concentration, attention, and reasoning.
- Also promotes tissue repair and maintains a healthy immune system.
- Continuous lack of sleep adversely affects health.
Stages of Sleep
- NREM (Non-Rapid Eye Movement) Stages: Stages 1, 2, 3, and 4 followed by REM (Rapid Eye Movement) considered Stage 5.
- Stage 1: Drowsiness occurs as one drifts off to sleep; brain waves are still relatively fast.
- Stage 2: The brain waves begin to slow down further, indicating deeper relaxation.
- Stages 3 and 4: Characterized as the deepest stages of sleep with the slowest brain wave activity and most restorative value.
- REM Sleep: Involves dreaming; occurs in cycles of sleep.
- Cyclical Nature of Sleep:
- One full cycle of sleep lasts approximately 90 minutes:
- The average individual undergoes 5-6 cycles per night if achieving 7 to 8 hours of sleep.
- First Sleep Cycle:
- NREM Duration: 80 minutes
- REM Duration: 10 minutes
- Last Sleep Cycle:
- NREM Duration: 60 minutes
- REM Duration: 30 minutes
- Note: REM sleep increases in duration as the night progresses, which is why dreams can often be recalled more vividly upon waking in the morning.