Sleep-wake disorders and examples

• A. Disorders involving sleep disturbance; examples include insomnia disorder, narcolepsy, circadian rhythm sleep-wake disorders, and restless legs syndrome
• B. Disorders of waking life due to brain injury
• C. Sleep disorders caused by medication only
• D. Mood disorders with sleep symptoms

Answer: (A)

Sleep-wake disorders refer to conditions in which sleep is disrupted in ways that cause distress or impairment, including trouble falling or staying asleep, sleeping too much, or having sleep that’s out of sync with the day-night cycle. The examples listed—insomnia disorder, narcolepsy, circadian rhythm sleep-wake disorders, and restless legs syndrome—illustrate the main ways this disruption can present. Insomnia is difficulty initiating or maintaining sleep despite opportunities to sleep. Narcolepsy involves sudden sleep attacks and daytime sleepiness often tied to abnormal regulation of REM sleep. Circadian rhythm sleep-wake disorders arise when there’s a mismatch between the internal clock and environmental cues, leading to shifted or irregular sleep times. Restless legs syndrome features uncomfortable sensations and an urge to move the legs, especially at rest, which disrupts sleep.

Other options describe different kinds of problems: disorders of waking life after brain injury focus on daytime functioning rather than primary sleep problems; sleep disorders caused by medication alone emphasize a specific causative factor rather than a broad sleep-wake disturbance; mood disorders with sleep symptoms involve sleep problems as part of another primary condition rather than a standalone sleep-wake disorder category.