Scientists at University College London suggest that a lack of routine can impair early development by disrupting the body clock, which can affect the brain’s ability to remember and learn new information.
Results showed that the effect was most striking in three-year-olds, among whom both boys and girls scored lower on math, reading, and spatial skills tests that children of the same age who adhered to rigid bedtime schedules.
"Age three seems to be where you see the largest effect and that is a concern," said lead researcher Amanda Sacker.
"If a child is having irregular bedtimes at a young age, they’re not synthesizing all the information around them at that age, and they’ve got a harder job to do when they are older," she added. "It sets them off on a more difficult path."
Sacker and her team analyzed data from 11,178 seven-year-old children from the UK Millennium Cohort Study, a long-term record of British children who are now nearing their teenage years.
While the hour that children went to bed had little or no consequence on their performance on different tests, having no set bedtime did, often leading to lower scores. Girls who never had regular bedtimes at ages three, five, and seven had significantly lower reading, math, and special scores. For boys, this was the case for those having non-regular bedtimes at any two of those ages.
The study was published online July 8 in the Journal of Epidemiology and Community Health.
A separate 2011 study from the University of South Australia reveals that children who go to bed earlier are less likely to be obese than those who stay up late.
Access the new study: http://jech.bmj.com/content/early/2013/06/25/jech-2012-202024
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