Spreading depression using chronically implanted electrodes

¹ Department of Physiology, Indiana University School of Medicine, Indianapolis, Indiana

Spreading depression (SD) was elicited from the cortex of rabbits in which an electrode assembly was implanted. A repetitive train of stimuli was used to elicit the phenomena. The presence of SD was shown by slow potential changes and diminution of direct cortical responses characteristic of SD in acute studies. A number of SD's could be produced on successive days, up to 2 weeks. These experiments show that exposure of the cortex is not a prerequisite for elicitation of the phenomena.