A new study led by UCL, University of East Anglia and University of Lyon researchers has found that people sleep less in mid-adulthood than they do in early and late adulthood. Sleep duration declines in early adulthood until age 33 and then picks up again at age 53, according to the findings published in Nature Communications. The study, involving 730,187 participants spread over 63 countries, revealed how sleep patterns change across the lifespan, and how they differ between countries. Study participants were playing the Sea Hero Quest mobile game, a citizen science venture designed for neuroscience research, created by Deutsche Telekom in partnership with Alzheimer's Research UK, UCL, UEA and game developers Glitchers. Designed to aid Alzheimer's research by shedding light on differences in spatial navigational abilities, over four million people have played Sea Hero Quest, contributing to numerous studies across the project as a whole.