The human circadian clock's seasonal adjustment is disrupted by daylight saving time

Publication Type:

Conference Proceedings


20th Anniversary Meeting of the Society for Research on Biological Rhythms, SRBR, Sandestin, FL, p.225 (2008)


circadian, Daqtometer V2.3, DST, human


About 1.6 billion people are subjected to daylight saving time (DST), a change in social, but not environmental clocks. We analyzed the changes in Mid-Sleep on Free Days (MSF) and Center of Activity (CoAct) for 8 weeks around both DST transitions in 50 subjects. MSF and CoAct adjust to the transition from DST in autumn, but CoAct does not adjust to the transition to DST in spring, especially in the late chronotypes.