[Recurrent tongue biting due to hypnic myoclonia in infancy]

We report a 15-month-old female infant who had recurrent tongue biting due to hypnic myoclonia. She began to bite her tongue and bleed when she was 9 months old. The tongue biting was accompanied by generalized myoclonus and was seen only during drowsiness. On admission at 15 months of age, she was observed by video-EEG monitoring. There were hypnic jerks with powerful closure of the mouth and severe screaming, but no accompanying evidence of epileptic discharges. The tongue biting with hypnic myoclonia disappeared spontaneously at 22 months of age, and was considered to be an age-dependent phenomenon related to the maturation of the brain and to the development of oral functions.