Jactatio nocturna after head injury.

Nocturnal head banging or body rocking often occurs in childhood in relation to sleep, and is generally considered a developmental or behavioral disorder. A few cases of jactatio nocturna have been considered manifestations of sleep disorder, and an analogy to somnambulism and pavor nocturnus has been suggested. We observed episodes of jactatio nocturna in a patient with global encephalopathy and frontal lobe dysfunction after closed head injury, and successfully treated these with imipramine. Sleep disorders are increasingly recognized after head injury; jactatio nocturna must be differentiated from post-traumatic seizures, and may represent partial or defective arousal during light non-REM sleep, analogous to the parasomnias of deeper sleep and possibly representing dysfunction of frontal arousal mechanisms.