Abstract
A new approach to study the effect of ischemia on the brain of the awake gerbil is described. The measurement of NADH fluorescence from the surface of the cortex is done by a time‐sharing fluorometer/reflectometer connected to the brain via a flexible light guide and an implanted cannula. The response of the gerbil brain to anoxia and spreading depression is described. By unilateral occlusion of the carotid artery and increase in NADH was measured in the ipsilateral hemisphere.