A renowned neurologist shares the true stories of people unable to get a good night's rest in The Nocturnal Brain: Nightmares, Neuroscience, and the Secret World of Sleep, a fascinating exploration of the symptoms and syndromes behind sleep disorders.

For Dr. Guy Leschziner's patients, there is no rest for the weary in mind and body. Insomnia, narcolepsy, night terrors, apnea, and sleepwalking are just a sampling of conditions afflicting sufferers who cannot sleep—and their experiences in trying are the stuff of nightmares. Demoniac hallucinations frighten people into paralysis. Restless legs rock both the sleepless and their sleeping partners with unpredictable and uncontrollable kicking. Out-of-sync circadian rhythms confuse the natural body clock's days and nights.

Then there are the extreme cases. A woman in a state of deep sleep who gets dressed, unlocks her car, and drives for several miles before returning to bed. The man who has spent…