1.1b_narcolepsy polysomnogram

These 24-hour sleep recordings of two individuals—one with a normal sleep pattern (top) and one with untreated narcolepsy—clearly demonstrate the disrupted nature of sleep and wakefulness in narcolepsy. The control subject has a regular pattern of rapid-eye-movement (REM) sleep (indicated in purple) and non-REM sleep (indicated as stages 1, 2, 3, and 4 of sleep) confined to an 8-hour sleep interval. In contrast, the untreated patient with narcolepsy has REM sleep at nighttime sleep onset, experiences a more fragmented sleep pattern, and displays REM sleep intruding even during naps during the daytime.