Girls ...but not boys...that did not have a set regular bedtime at age 7 had significantly lower scores for reading, math, and spatial skills on standardized tests from UC London researchers.
Non-regular bedtimes at age 3 were independently associated with lower cognitive skills at age 7 in BOTH girls and boys.
The study suggests that when sleep is restricted or disrupted symptoms symptoms that reflect a reduced capacity for plastic change in the brain.
The implication is that reduced or disrupted sleep , particularly if it occurs at key times in development, could have important impacts on health throughout life.
Y. Kelly,PhD Jrnl of Epidemiology and Community Health July 2013