During the second half of the 1st year, periods of increased sleep disruption have been documented alongside overall improvement in sleep-wake regulation. The objective of the present research was to test if pulling-to-stand (PTS), a milestone typically achieved during the latter part of the 1st year, co-occurs with a period of disrupted sleep. In a longitudinal design, 20 healthy infants were followed-up, from 7 to 11-12 months, at 3-week intervals. Each measurement consisted of filmed motor observations and sleep recordings (actigraphy), both conducted at home. It was found that among early achievers of PTS (by 8 months), the milestone was time-linked to a period of disrupted sleep. The results point to the significance of timing in the interplay between domains of development, and highlight the importance of considering both chronological and developmental metrics in studying changes in sleep-wake regulation.
Bibliographical noteFunding Information:
A part of this study has been supported by a grant from the Israel Science Foundation ( # 228/07 ). We thankfully acknowledge the contribution of Moran Samuel in data collection and coding, and of Sandra Zukerman for her continuous assistance in data management and analysis. We extend our thanks to the parents and children who enthusiastically participated in this study.
© 2015 Elsevier Inc.
- Developmental change
ASJC Scopus subject areas
- Developmental and Educational Psychology