Familial benign neonatal sleep myoclonus.

Benign neonatal sleep myoclonus is a nonepileptic syndrome characterized by myoclonic jerks during sleep. It occurs in the first weeks of life and disappears, in most cases, within 3 months. There are no sequelae, and psychomotor and cognitive development are normal. The syndrome is usually sporadic; only a few familial cases have been reported in the literature. This case report describes three members of a single family with benign neonatal sleep myoclonus and discusses its differentiation from other types of myoclonus.