Regular Bedtime Is More Important For Girls' Brains Than Boys'

Before the age of seven, a girl's cognitive development is
greatly affected by a regular bedtime.

Out of the 11,000 children participants in a
long-term study, seven-year-old girls who didn't have regular
sleep schedules had IQ scores approximately nine points lower
than their peers, based on cognitive tests in reading, maths, and
spatial awareness.

Boys without regular sleep schedules seem to only be
temporarily affected. The group of researchers at
the University College,
London found that boys with irregular bedtimes were
recorded as having an IQ approximately six points lower than
their peers at age three, but this gap diminished by age seven.
The researchers have no explanation as to why sleep affects boys
and girls differently.

In the past, sleep experts have argued that an earlier
bedtime is beneficial for children.

"I think the message for parents is … maybe a regular
bedtime even slightly later is
advisable," Amanda Sacker, director of the
International Center for Lifecourse Studies in Society and Health
at University College London and a co-author of the study,
told Sumathi
Reddy in The Wall Street
Journal.

The researchers found that brain power is heavily affected
by disruptions in the circadian rhythm during childhood years.
This means that irregular bedtimes can disrupt a body's natural
development and growth, which then affects the brain's ability to
understand and retain information.

The authors wanted to see whether bedtimes in early
childhood were related to cognitive development. All of the
participants were born between Sept. 2000 and January
2002, and were visited by researchers at
ages nine months and three,
five, and seven years.

More than half of the children in the study went to bed
between 7:30 and 8:30 p.m. and the researchers also
accounted for factors such as skipping breakfast or watching too
much television.