Abstract
Sleep of two lissencephalic children was studied. The sleep-waking cycle was recorded for a long period, and the all-day polysomnography was carried out twice on each case.
Case 1 was a 1-year-old boy of agyria, and case 2 was a 2-year-old boy of pachygyria. Clinically, both were severely retarded, hypotonic and suffering from seizures of infantile spasms. The sleep-waking cycle of case 1 showed alternating periods of free-running and chaotic rhythms. The cycle of case 2 showed a typical free-running rhythm. The all-day polysomnography in both cases disclosed that the REM time decreased as the frequency of seizures increased. These seizures showed a periodicity closely related to the REM cycle.
Various characteristics of the REM sleep in adults were recognized also in our cases. Every physiological parameter including EEG, eye movements, chin EMG, body movements and respiration, fluctuated in a rhythmic and mutually synchronized manner, although each showed abnormality commonly encountered in cases of infantile spasms.
The clocks of circadian and ultradian rhythms were preserved in the lissencephalic brains which were morphologically similar to those of normal fetuses in the fourth month of gestation. However, these clocks synchronized poorly with their environments. The most conspicuous disturbance of the sleep in lissencephaly was the lack of entrainment.
