Relation between polysomnographic measures during nocturnal sleep and a quotient of behavioral development in infants with developmental disabilities.

Polysomnographic features during nocturnal sleep were investigated in 27 infants with developmental disabilities. With the use of a multiple regression analysis, 78% of the variance of a Development Quotient (DQ) measured by a questionnaire on behavioral development for infants was explained by sleep measures. Of 14 sleep measures employed in the study, (1) cumulative awakening time during a nocturnal sleep time, (2) duration of REM stage, and (3) percentage of REM to total sleep time were important in association with the DQ. The findings are consistent with the sleep-cognition hypothesis proposed by Espie, et al.