Unihemispheric sleep deprivation in bottlenose dolphins

SUMMARY  Unihemispheric and bihemispheric sleep deprivation were performed in bottlenose dolphins. One brain hemisphere was capable of being deprived of delta (0.5‐3.0 Hz) sleep in the former condition. Here, an increase in sleep pressure was observed during sleep deprivation in the deprived hemisphere. In the recovery sleep, following unihemispheric sleep deprivation, there was a rebound of delta sleep only in the deprived hemisphere. Following bihemispheric sleep deprivation the animals exhibited an increase in delta sleep in both hemispheres.