Actigraphic sleep and developmental progress of one-year-old infants

The aims of this study were to pilot methods to monitor the sleep of infants, as well as explore the relationships between infant sleep and physical, cognitive and motor development. Fifty-two one-year-old infants and their parents participated in the study. Infant sleep was assessed by one week’s actigraphy, sleep diaries and by the Brief Infant Sleep Questionnaire. Parents also completed a background questionnaire and the Ages and Stages Questionnaire to measure stages of development across five domains. Infant’s weight and length were measured by the researcher at study onset and Body Mass Index (BMI) scores were calculated. Sleep efficiency, and having a higher proportion of total sleep at night, were significantly correlated with age as well as stages of cognitive and motor development. However, sleep measures were not correlated with infant BMI. These findings support increasing evidence that sleep matures quickly around the age of one year and is related to other stages of development. Further research is required to confirm whether links between sleep and development are simply a marker of maturation, or if sleep per se plays a specific role in infant cognitive and motor development. Sleep and physical growth at this age need further investigation with a more representative sample including short-sleeping and overweight infants.