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Infant motor activity during sleep: Simultaneous use of two actigraphs comparing right and left legs
Osnat Atun-Einy1, Lorenzo Tonetti2, Michele Boreggiani2
1Department of Physical Therapy, University of Haifa, Haifa, Israel.
Insights
Infant motor asymmetry during sleep is not present in the first year of life. Further research is needed to understand the development of sleep-wake motor patterns and potential limb differences.
Area of Science:
- Developmental neuroscience
- Sleep research
- Motor control
Background:
- Adults exhibit motor asymmetry during sleep, with higher activity in the non-dominant limb.
- The developmental origin of motor asymmetry during sleep remains unclear.
Purpose of the Study:
- To investigate the emergence of motor asymmetry in infants during sleep.
- To compare motor activity between the right and left legs in healthy infants aged 7 to 12 months.
Main Methods:
- Longitudinal study of 20 healthy infants from 7 to 12 months of age.
- Motor activity was recorded using twin actigraphs (AMI) every 3 weeks.
- Analysis focused on the first seven hours of nocturnal sleep, comparing limb activity hour-by-hour.
Main Results:
- No consistent differences in leg motor activity levels were found between the right and left legs.
- Analysis using standard infant sleep algorithms revealed discrepancies in night waking detection (33% of nights).
- Leg movement data suggest motor asymmetry is not yet present in the first year of life.
Conclusions:
- Motor asymmetry, as measured by leg activity, does not appear to be present during the first year of infant development.
- Significant discrepancies in detecting night waking episodes warrant further investigation into the developmental trajectory of circadian motor asymmetry.
Abstract:
Motor asymmetry during the first hours of sleep documented in adults found higher activity in the non-dominant limb. The stage of development at which such asymmetries first appear is unknown. Twenty healthy infants were followed from 7 to 12months of age, at 3-week intervals, comparing motor activity of the right and left legs during sleep using twin actigraphs (AMI). Hour-by-hour analysis of the first seven hours of nocturnal sleep found no consistent difference in activity levels between the right and left legs. Using the standard algorithm for infants, which provides an overall estimate of sleep quality, revealed discrepancies in night waking episodes (Right versus Left) in 33% of the nights. Results pertaining to leg movement suggest that motor asymmetry is not yet present during the first year of life. However, given the large discrepancies in the detection of night waking, further investigation of the developmental course of circadian motor asymmetry is warranted.
