In a study that followed nearly 1,500 Canadian children from birth to age 6, researchers found that those who slept less than 10 hours per night in their preschool years were more likely to show problems with their verbal and spatial skills by school-age.
These children also tended to be more hyperactive and impulsive than their peers who slept longer.
The findings, say the study authors, highlight the importance of young children getting at least 10 hours of sleep each night.
The aim of the study, led by Dr. Jacques Y. Montplaisir of the University of Montreal and the Sleep Disorders Center at Sacre-Coeur Hospital , was to investigate the associations between longitudinal sleep duration patterns and behavioral/cognitive functioning at school entry. It followed 1,492 Canadian children born between 1997 and 1998. Each year, mothers reported on their children’s typical sleep patterns, from the time the children were 2.5 years old until they were 6.
The researchers found, children who were habitual short sleepers were three times more likely to score poorly on a standard test of language skills than children who consistently slept at least 10 hours.
Also  children who increased their sleep time as they got older remained at risk of problems — including hyperactivity and poor scores on a test of visual and spatial skills.
Source: Sleep Sept 1 2007
