WORLD CAPITALS, 24th April, 2025 (WAM) -- Teenagers who go to bed earlier and enjoy longer sleep tend to have sharper mental skills and perform better in cognitive tests, according to new research.
A study involving more than 3,000 adolescents revealed that those who went to bed the earliest, slept the longest and had the lowest resting heart rates during sleep outperformed their peers in reading, vocabulary, problem-solving and other cognitive assessments.
While researchers anticipated that teenagers with healthier sleep habits would score higher, they were surprised by the significant impact even small differences in sleep patterns could make.
“We think that it’s the sleep driving the better cognitive abilities, in part because we consolidate our memories during sleep,” said Barbara Sahakian, a professor of clinical neuropsychology at the University of Cambridge.
Sahakian’s team and researchers at Fudan University in Shanghai analysed data from 3,222 young people in the adolescent brain cognitive development study, the largest long-term investigation into brain development and child health in the US. Those who took part had brain scans, cognitive tests, and tracked their sleep using Fitbits.
Despite the healthier habits of some teenagers, the study found that even the best sleepers were not meeting recommended sleep durations. The American Academy of Sleep Medicine advises that those aged between 13 and 18 should sleep for eight to 10 hours per night.
The participants were divided into three distinct sleep pattern groups. The first group, comprising 39 percent, went to bed the latest and woke the earliest, averaging seven hours and 10 minutes of sleep. The second group, 24 percent, averaged seven hours and 21 minutes of sleep.
The third group, accounting for 37 percent, went to bed the earliest, slept the longest and had the lowest sleeping heart rates, with an average of seven hours and 25 minutes of sleep.
Professor Sahakian described the results as “surprising”, noting that small differences in sleep duration appeared to significantly influence outcomes. “It suggests that small differences in sleep amounts accrue over time to make a big difference in outcomes,” she said.
To improve sleep and support better mental performance, Sahakian recommends regular physical activity and avoiding the use of mobile phones or computers in the late evening.