Developing the next generation model for predicting circadian phase from personal light exposure
Abstract
A research team from the Center for Effective Light (CEL) at Mount Sinai led by Dr. Mariana Figueiro will develop and test a mathematical model to more accurately predict circadian phase based on personal light-dark exposure patterns. This mathematical model will be integrated into the circadian monitoring and regulation (CMR) system currently funded by the Army Research Office. The CMR system is envisioned to allow field commanders to evaluate and modify individual light-dark exposure patterns to better align the circadian phases of warfighters to their active duty responsibilities. Circadian rhythms are the platform for all biology on Earth. All species go through a 24-hour cycle of physiology and behavior. Diurnal species such as humans should be awake and active during the day and asleep and resting at night. In the natural environment our endocrine and neural functions are all coordinated with sunrise and sunset in support of our diurnal niche. The 24-hour light-dark cycle incident on the retina is the primary stimulus that controls circadian entrainment to our local position on Earth. However, warfighters do not live in a natural environment. They are often required to be active and alert during the night for special operations. Even those warfighters who are expected to be active during the day may spend all this time indoors in secure, windowless environments. Consequently, warfighters in the field and at home commonly lose their entrainment to the local, 24-hour light-dark cycle. When the pattern of light and dark does not follow a robust, 24-hour light-dark cycle performance and health are demonstrably compromised. The CMR system is designed to accurately capture the personal light-dark exposure patterns that entrain or disrupt the otherwise self-sufficient 24-hour oscillations in the brainÕs biological clock. Researchers from CEL have developed such a system. CEL researchers have the basic knowledge of light and circadian system regulation as well as a proven, field tested platform for making and evaluating circadian disruption. CEL researchers developed the most comprehensive physiologically-based model of circadian phototransduction, so is uniquely able to quantify circadian-effective light as a stimulus for circadian entrainment and disruption. CEL researchers have also developed the first calibrated, field-tested, personal light and activity measurement device shown to be acceptable by users. In this project, the research team from CEL will improve the mathematical model of the biological clock presently incorporated into the CMR system. As exists now, input to the mathematical model will be calibrated, personal light-dark exposure patterns. To accomplish this objective, the research team will first perform a comprehensive review of the literature that has attempted to mathematically relate light-dark exposure patterns to circadian phase. Based on this review and work the CEL team has been doing over the past decade the neurophysiology of circadian phototransduction, the research team will develop a preliminary model for the circadian system where personal light-dark exposure patterns predict circadian phase. The team will then test and validate this model for accuracy using data collected by the CEL team in number previous studies where personal light-dark exposure patterns were recorded. The research team will upgrade the model for prediction accuracy and then explore the behavior of the model when presented with different types of lighting scenarios. This will enable us to learn how different characteristics of the light-dark exposure pattern affects circadian phase, including the relative significance of amount, spectrum, timing, and duration. From this sensitivity analysis, the team will generate a priori predictions for subsequent empirical testing, specifically regarding timing for application of circadian-effective light doses. A final report will be prepared suitable for publication and pr
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jun 25, 2021
- Source ID
- W911NF2110183
Entities
People
- Mariana Figueiro
Organizations
- Army Contracting Command
- Icahn School of Medicine at Mount Sinai
- United States Army