Current theories of depression suggest that sleep problems, low energy, and low activity levels result from depressed mood, but a new study looking at interactions among these factors in people with bipolar disorder or depression suggests that the opposite may be true—that instability in activity and sleep systems could lead to mood changes. The findings, published online December 12 in the journal JAMA Psychiatry, suggest new targets for depression treatment.
Previous research has shown the interrelated nature of many of the homeostatic systems of the body. For example, the regulation of motor activity has been found to be linked with other systems, such as those regulating sleep, activity, and emotional states. While dysregulation in these systems is often seen in people with mental disorders, it can be challenging for researchers to examine both the interrelationships between multiple systems and their directional influences using traditional clinical assessments based on retrospective recall.