Simultaneous multi-wavelength optical imaging of neuronal and hemodynamic activity

Abstract

Functional brain imaging techniques, such as functional magnetic resonance imaging, infer changes in underlying neural activity from perfusion-related signals and can be sampled from large areas of cortex to examine hemodynamic network activity. However, measurement of the underlying neuronal activity in a correspondingly widespread network is not available for comparison. In order to accurately understand the origins of these hemodynamic signals and the mechanisms of neurovascular coupling, it is critical to be able to measure widespread neuronal activity simultaneously and homotopically with the vascular signal. For this reason, we designed a simultaneous multi-wavelength optical imaging system that can provide highresolution spatiotemporal information of neuronal and hemodynamic activities, and their inter-relationship. We have demonstrated that this technique is an effective method with which to study neurovascular coupling during spontaneous brain activity, and pathological conditions such as epilepsy.