The Use of Time Lapse Video Recording of Sleep‐Wake Behavior in Human Infants

The present study describes the use of time lapse video recording or sleep‐wake states in human infants. Polygraphic studies were carried out simultaneously to evaluate validity. Six normal, full‐term infants were each recorded twice: first at 2 weeks and again at K weeks of age. Behavioral and physiologic states were scored from the video and polygraphic records, respectively, according to standard criteria. Interrater reliability for the video tapes was .92. In comparing the polygraphically determined states with the video scoring, a significant overall product‐moment correlation of .79 was obtained for all states and ages. Similarly, the individual state correlations at both ages were statistically significant between the systems. Wakefulness was the most highly correlated state. Active‐REM sleep was more highly correlated in the younger age group, while quiet‐NRKM was more highly correlated in the older age group.