Overview
This lecture discusses various sleep disorders, including insomnia, sleep apnea, sleepwalking, and sleep paralysis, explaining their causes, symptoms, and potential treatments.
Sleep Paralysis
- Sleep paralysis is temporary inability to move or speak while falling asleep or waking up.
- Up to 40% of people experience sleep paralysis at some point.
- It can include hallucinations and a sense of pressure on the chest.
- Occurs when you wake during REM sleep, while muscles are still paralyzed to prevent acting out dreams.
- Neurotransmitters GABA and glycine help inhibit muscle activity during REM sleep.
Insomnia
- Insomnia is prolonged difficulty falling or staying asleep.
- Traditionally seen as a symptom, now often considered a chronic disease itself.
- Primary insomnia occurs without other medical conditions; secondary insomnia accompanies other health issues.
- Acute insomnia is short-term, often stress-induced; chronic insomnia lasts more than a month.
- Hyper-arousal (constant fight-or-flight state) is believed to be a key cause of chronic insomnia.
Sleep Apnea
- Sleep apnea interrupts normal breathing during sleep and often goes unnoticed by the sufferer.
- Obstructive sleep apnea is caused by throat muscles collapsing, blocking the airway.
- Severe sleep apnea can cause heart failure, stroke, and is linked to diabetes.
- CPAP machines are commonly used to keep airways open during sleep.
- Central sleep apnea is rarer and results from the brain failing to signal the body to breathe.
- New treatments include pacemaker-like devices to stimulate breathing during sleep.
Sleepwalking (Somnambulism)
- Sleepwalking affects about 15% of people, more commonly children aged 3–7.
- Occurs during deep non-REM sleep, usually early in the night.
- Causes may include bypassing sleep stages, underdeveloped GABA systems, genetics, or external factors.
- Genetic predisposition linked to a defect on Chromosome 20; 50% chance of inheritance from a parent.
- Can involve walking, eating, or talking while asleep.
Key Terms & Definitions
- Sleep Paralysis — Temporary inability to move or speak during the transition between sleep and wakefulness.
- Insomnia — Persistent problems with falling or staying asleep.
- Hyper-Arousal — Prolonged state of heightened alertness, contributing to insomnia.
- Sleep Apnea — Disorder where breathing repeatedly stops and starts during sleep.
- Obstructive Sleep Apnea — Airway blocked by throat muscles during sleep.
- Central Sleep Apnea — Brain fails to send proper signals to muscles controlling breathing.
- CPAP Machine — Device that delivers air pressure via a mask to keep airways open.
- Sleepwalking (Somnambulism) — Performing activities while asleep, usually during non-REM sleep.
- GABA — Neurotransmitter that inhibits motor activity in the brain.
Action Items / Next Steps
- Review definitions of key sleep disorders.
- Learn how sleep cycles (REM and non-REM) relate to these conditions.
- Prepare questions about sleep disorders for class discussion.