To Sleep, Perchance to Walk
With insomnia drugs yielding bizarre side effects, sleepwalking has wandered back into public consciousness.
Act and scene of Shakespeare’s Macbeth in which Lady Macbeth is spied sleepwalking
6Number of diagnostic criteria established by the American Psychiatric Association for sleepwalking disorder
1–7Approximate percentage of adults who experience a sleepwalking episode, compared with 0.5% who suffer from sleepwalking disorder
10Number of times more likely that sleepwalking will occur in close relatives of sleepwalkers than in the general public, suggesting a genetic component
6.9Percentage of sleepwalking reported for girls; 5.7% for boys
15Age by which occasional episodes of sleepwalking usually disappear without treatment
70Approximate number of cases of homicidal somnambulism, or sleepwalk murder, reported in history
1846Year in which the lawyer of Albert Tirrell, accused of murder, mounted a sleepwalking defense
13Number of sleep medications, including Ambien and Lunesta, for which the Food and Drug Administration has requested added warning language about “complex sleep-related behavioral side effects,” such as driving, making phone calls, preparing and eating food, and having sex while asleep


