Study Finds Early Sleepers Among Teens Perform Better at Cognitive Tests
Young people who go to bed earlier and get more sleep tend to perform better on reading, vocabulary, and problem-solving tests, according to a major new study.
Researchers from the University of Cambridge and Fudan University in China analysed the sleep habits of over 3,000 adolescents using Fitbits and found that even minor differences in bedtime and sleep length were linked to noticeable differences in brain development and test performance.
While none of the groups showed a clear advantage in school grades, teens who fell asleep earlier and maintained the lowest sleeping heart rates had the largest brain volumes and the strongest results on cognitive tasks.
“These results really surprised us,” said Professor Barbara Sahakian from Cambridge’s Department of Psychiatry. “The average difference in sleep time between the best and worst sleepers was just 15 minutes — yet this had measurable effects on brain function.”
The study, part of the American ABCD research project, found the ideal amount of sleep for teens is between eight and ten hours per night. Most participants averaged just over seven hours.
Lead researcher Dr Qing Ma added: “We can’t prove that better sleep causes better performance — but the evidence supporting that link is growing fast. Sleep supports memory, learning, and focus. It’s a vital part of brain health.”
📍 For parents, educators, and young people in Sunderland and beyond, the message is simple: shut down the screens earlier and make sleep a priority. Even small changes can make a big difference.
