(BBC) — Late nights and lax bedtime routines can blunt young children's minds, research suggests.
The findings on sleep patterns and brain power come from a UK study of more than 11,000 seven-year-olds.
Youngsters who had no regular bedtime or who went to bed later than 21:00 had lower scores for reading and maths.
Lack of sleep may disrupt natural body rhythms and impair how well the brain learns new information say the study authors.