SPONTANEOUS MOVEMENTS DURING SLEEP IN CHILDREN - TEMPORAL ORGANIZATION AND CHANGES WITH AGE

Developmental changes in the temporal organization of spontaneous move ments during sleep was studied in children between 9 months and 11 yea rs of age. Subjects were monitored in the home environment for the ent ire sleep period using actigraphy and videography. Rhythmicity in slee p-related spontaneous movements was examined using FFT and chi-square periodogram time series analyses. A dominant periodicity of 60-120 min utes was identified which was found to progressively lengthen with age . A microanalysis of the temporal structure of movements revealed a de velopmental decline in bout duration, but a paradoxical ina ease in bo ut frequency. These results show that motor activity becomes less robu st and more fragmented as development progresses while retaining under lying rhythmic integrity, and argue for the dynamic influence of CNS m aturation on the organization and expression of sleep-related spontane ous movements. (C) 1998 John Wiley & Sons, Inc.