Longitudinal Study of Infant Sleep: Results of 14 Subjects Studied at Monthly Intervals

Abstract
The sleep of 14 normal infants was studied every month throughout the first year. A computer program incorporated an analysis of multiple variables from polygraphic data as recommended by a recently standardized new born scoring manual. Under our recording conditions, quiet sleep increased during the first 3 months but indeterminate sleep did not decline over the year as expected. This finding is incompatible with the notion that indeterminate sleep reflects immaturity or “undifferentiation” in sleep organization.