Glial cells called astrocytes are abundant in the central nervous system. They play an important role in healthy brain function, including mediation of neurovascular coupling–the process by which active neurons signal to blood vessels to increase local blood flow and hence the supply of energy substrates. This process underlies several non-invasive neuroimaging techniques applied to human cognitive research and clinical diagnosis, with one prominent example being functional magnetic resonance imaging. Dr. Mishra has studied mechanisms of neurovascular coupling for over 15 years. She performed her doctoral research in the laboratory of Dr. Eric Newman at the University of Minnesota, where she studied the role of astrocytes in retinal neurovascular coupling impairments in diabetes and hyperoxic conditions. She then moved to University College London to do her postdoctoral work with Dr. David Attwell, where she demonstrated that astrocyte-mediated signaling is essential in regulating capillary blood flow in the cortex. She also found that pericytes often constrict capillaries and then die following ischemia, severely reducing blood supply to the afflicted region.

Neurovascular coupling is very robust under healthy mature conditions. However, in pathological/disease contexts, neurovascular coupling is often altered. This not only results in a mismatch of energy supply and demand in the brain but also complicates the interpretation of neuroimaging data from patients. Current research in the Mishra lab is aimed at understanding the mechanisms of neurovascular coupling in health and disease, with a focus on the role that astrocytes play in these processes.