Characterization of cortical spreading depression by imaging of intrinsic optical signals

The spatiotemporal progression of cortical spreading depression was investigated by imaging of activity-dependent intrinsic optical signals in rat sensorimotor cortex. In contrast to the traditional conception of a uniformly propagating event, the evolution of the spreading depression was characterized by an asymmetrical propagating wavefront and a non-uniform dispersion of optical signals behind the wavefront. As these optical signals are a reflection of underlying molecular and metabolic processes, the imaging approach to spreading depression might constitute a useful technique for investigating the functional organization as well the pathophysiology of the cerebral cortex.