Clinical Reasoning: A 45-year-old man with progressive insomnia and psychiatric and motor symptoms.

A 45-year-old right-handed hypertensive man presented with a 6-month history of worsening neuropsychiatric symptoms, abnormal movements, and weight loss. He was hallucinating, apathetic, and having severe insomnia (total sleep duration of 1–2 hours/night). During sleep, his wife noted labored and sonorous breathing. Six months before admission, he led a healthy and active lifestyle.