Benign Neonatal Sleep Myoclonus
Benign neonatal sleep myoclonus can only be diagnosed in neurologically normal fullterm neonates. The diagnosis requires a clear history or the observation of repetitive myoclonic limb jerks that occur only during sleep (click on clips) and stop upon awakening.

The myoclonic activity may last from several seconds to 90 minutes. The jerks may be felt while the limb is held (click on third clip).

Benign neonatal sleep myoclonus may be triggered and exacerbated by noise, rocking, and benzodiazepines. Rocking is especially effective in triggering the events (click on third clip).

The use of benzodiazepines to eliminate benign neonatal sleep myoclonus may lead to sustained myoclonus and to the misdiagnosis of status epilepticus. Benign neonatal sleep myoclonus is not associated with electroencephalographic seizures during the events. A 10% to 30% increase in heart rate occurs during some events. Interictally, the EEG is normal.Benign neonatal sleep myoclonus may occur during any sleep stage but it occurs more frequently during quiet sleep. The mechanism of benign neonatal sleep myoclonus is unknown. Immaturity or imbalance of the serotonergic system has been postulated. In most cases there is no family history of similar events. Benign neonatal sleep myoclonus usually disappears before 6 months of age and requires no treatment. Benign neonatal sleep myoclonus is not associated with subsequent neurological deficit.