Predicting Circadian Phase Shift

The Circadian Monitoring and Regulation (CMR) system is comprised of a light sensor worn as a button on the collar or shirt and an activity sensor worn on the wrist. A modified Kronauer model of human circadian entrainment (circadian stimulus, CS-oscillator model) was incorporated into an app to deliver a light prescription to advance or delay circadian phase. The CS-oscillator model uses personal light exposures to predict circadian phase. The phone app is connected to the light and activity sensor via Bluetooth. The goal of the present study was to determine whether the CMR system delivering a light prescription designed to advance the circadian phase of participants by 4 hours would lead to similar phase advance in the dim light melatonin onset (DLMO).