Drs. Agung Julias and John Wen‘s methodological approach to assess circadian processes in subjects who have recently experienced traumatic brain injury, using regularly gathered intracranial temperature data. The health effects of circadian regulation are profound, yet assessments of circadian processes are often infeasible in the neurotrauma intensive care unit (ICU).

Circadian entrainment, the alignment in periodicity and phase of the sleep–wake cycle with respect to the solar cycle, drives underlying biological oscillators and is altered by exposure to light, exercise, eating, and regular patterns of sleep. Circadian desynchronization is associated with problems such as fatigue, irritability, weight gain, and impaired short-term memory.  Chronic circadian desynchronization is often present in subjects with head injuries, including traumatic brain injury (TBI) and subarachnoid hemorrhage (SAH), and is part of the high cost of TBI ($76.5B annually). The specific mechanisms responsible for the relationship between circadian desynchronization and TBI are not well known, however clinical observations suggest that circadian desynchronization is established during the acute phase of recovery, and has an immediate and lasting impact. Learn more about Julias and Wen’s work in assessing circadian rhythms and entrainment via intercranial temperature after sever head trauma in Vol. 54 of Biomedical Signnal Processing and Control.