Figure 1

Actigraphy data analysis. a, actual actigraphy data from a representative control child. Horizontal row shows activity data over 24 h (12 noon to 12 noon). Black bar indicates the movements in one min, purple lines indicate the bad periods (periods when the subject apparently removed the actigraphy instrument), red underlines indicate the sleep period as calculated by the software using the Kripke-Cole algorithm, and the light blue indicates DOWN periods, when the subjects are thought to be in bed. UP periods are defined as the remaining period after DOWN periods are removed. b, histogram of the bins according to the degree of movement. Horizontal bar indicates the number of movement counts in a one minute bin by the actigraphy. The vertical line at 138 indicates the threshold determined by the k-means clustering algorithm. c, double logarithmic plots of the cumulative probability of the rest bout for this subject. d, double logarithmic plots of the cumulative probability of the activity bout for this subject.