Defining Factors that Extend Circadian Entrainment Capabilities of Mammals
Abstract
Both shift-work and jet-lag are national security concerns as a result of their effects on military personnel. Mice, like humans and all other mammals, exhibit robust daily rest/activity cycles that are regulated by a biological clock in the hypothalamus synchronized to the local environment by the light/dark cycle. Because the ability of light to reset the clock is limited, it takes several days for mammals to adjust to rapid travel across time-zones (i.e., jet-lag) or to alter circadian phase to accommodated night-time work schedules at substantial cost in productivity, safety and health. This project established that simple light manipulations allow extraordinary entrainment in mice to schedules that are or could be used by military personnel including 18-30 h days and rotating shift-work. Such manipulations minimize performance decrements associated with shift-work. Enhanced circadian flexibility is shown to be intrinsic to the circadian pacemaker in the brain and likely reflect dampening of molecular circadian oscillators. Gender, age and lighting parameters modulate circadian plasticity. The results clearly establish an unprecedented capacity of the circadian clock of mammals to permit sleep/rest at artificial schedules of great utility for military operations and suggest approaches for translation of this work from rodents to humans.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 28, 2019
- Accession Number
- AD1070642
Entities
People
- Michael R Gorman
Organizations
- University of California, San Diego