Changes in heart rate variability in response to chronic circadian disruption with and without sleep restriction 

2022 Focused Projects Grant for Junior Investigators 

Robin Yuan, PhD 
Brigham and Women’s Hospital/Harvard Medical School 

Key Project Outcome

This project looked at changes in heart rate variability (HRV) during 3 weeks of exposure to circadian disruption with and without sleep restriction. We found a decrease in parasympathetic activity during exposure to circadian disruption with concurrent sleep restriction, but no change in HRV during exposure to circadian disruption when sleep loss was minimized. More research is needed to clarify whether this is due to sleep restriction contributing a larger impact on autonomic activity, or if this is due to an additive effect of circadian disruption and sleep loss together.