sleep disorders

Stage 1 NREM Sleep

Light sleep, dozing off, ~5% of adult sleep

Stage 2 NREM Sleep

"True" sleep, sleep spindles and K-complexes, ~50% of sleep

Stage 3 & 4 NREM Sleep

Deep sleep (slow wave), delta waves, 10–20% of sleep

REM Sleep

Dreaming stage, body paralysis, starts ~90 mins into sleep, ~20–25% of sleep

Sleep Efficiency

Time asleep ÷ time in bed; normal = 85%+ over 2 weeks

EEG (Electroencephalogram)

Measures brain activity during sleep

Sleep Cycle Variability

Varies by age; children adolescents need more sleep, REM declines with age

Insomnia Disorder

Trouble falling or staying asleep ≥3 nights week for ≥3 months

Causes of Insomnia

Stress, anxiety, trauma, poor sleep habits

CBT-I (for Insomnia)

Best treatment; includes sleep restriction, stimulus control, cognitive restructuring

Stimulus Control Therapy

Make bed only for sleep, avoid other activities, get up if unable to sleep

Sleep Restriction Therapy

Limit time in bed to actual average sleep time + 30 mins

Sleep Diary

Logs sleep habits and efficiency; used for assessment

Hypersomnolence Disorder

Excessive sleepiness despite 7+ hrs sleep, ≥3x week for ≥3 months

Narcolepsy

Sudden uncontrollable sleep attacks, cataplexy, sleep paralysis

Obstructive Sleep Apnea (OSA)

Upper airway blocked during sleep, linked to obesity, treated with CPAP

OSA Health Risks

Stroke, depression, heart disease, Type 2 diabetes, erectile dysfunction

CPAP Therapy

Air pressure mask to keep airway open; improves quality of life

Parasomnias

Unusual behaviors during sleep transitions (e.g., sleepwalking, night terrors)

Nightmare Disorder

Recurrent distressing dreams during REM; causes awakening and distress

Sleep Terror Disorder

Sudden waking in panic during NREM; common in children, no dream recall

Sleepwalking Disorder (Somnambulism)

Complex motor activity while asleep, common in kids 8–12

Restless Legs Syndrome (RLS)

Crawly aching feeling relieved by movement, ≥3x week for 3 months

Nocturnal Myoclonus (PLMS)

Periodic limb movements twitches during sleep

Isolated Sleep Paralysis

REM atonia upon waking; often misinterpreted as supernatural, not a disorder

Conditioned Arousal

Bed becomes associated with distress; common in insomnia and sleep paralysis

CBT-I vs Sleep Meds

CBT-I has longer-lasting effects, no tolerance risk; meds (like zolpidem) are short-term

Imagery Rehearsal Therapy (IRT)

Rewrites nightmares and rehearses new, safe versions to reduce distress