Regional differences in propagation of spreading cortical depression in the rabbit.

Abstract

Summary1. Of 36 rabbits consistently exhibiting spreading depressions and slow potential changes in response to galvanic stimulation of the cortex, only one exhibited propagation of these phenomena into that part of the area cingularis which is situated on the dorsal aspect of the hemisphere. Occasional small deflections recorded from this area were interpreted as evidence of physical spread of typical slow potential changes in nearby cortex. 2. Where previously absent, typical slow potential changes and spreading depressions were produced in the cingular area by a) prolonged exposure of the cortex, b) intravenous infusion of concentrated sucrose solution, c) cooling of the cortex, d) treatment of the cortex with isotonic sucrose solution, and e) with Ringer's solution containing 10 times the normal amount of potassium. 3. Asphyxial potentials were recorded both from the cingular area and from the cortex on the convexity of the hemisphere. However, the latent period of this potential from the cingular are...