Selective deprivation of sleep in pycnoleptic children. Effects of deprivation of slow-wave and REM sleep on the frequency and duration of petit mal attacks.

1. Selective deprivation of slow-wave and paradoxical sleep was performed in 10 children with pycnoleptic attacks (8 of them before anticonvulsive treatment, 2 of them while under medication). The frequency and duration of petit mal attacks were intraindividually compared during night sleep and after waking for a 5-h period. 2. After deprivation of slow-wave sleep with reduction of EEG stages 3 and 4 to about one-third of the baseline but normal duration of sleep, petit mal attacks are more frequent and long-lasting than after normal sleep or selective deprivation of REM sleep. 3. Although total sleep time is significantly diminished after selective deprivation of paradoxical sleep the frequency of attacks during the waking state was lower than after normal sleep and deprivation of slow wave sleep. This observation shows a clear i nfluence of the quality of sleep on the frequency of epileptic attacks. 4. During sleep petit mal seizures were mainly found during stages 2 and paradoxical sleep. Single spike and irregular spike were discharges, however, occurred more frequently during slow-wave sleep. Their frequency was not significantly different in the deprivation conditions. 5. In contrast to experimental data in animals, REM deprivation is less provoking to epileptic attacks outside sleep than deprivation of stages 3 and 4 sleep. Therefore a sufficient amount of slow-wave should be preserved for pycnoleptic children.