Independent coding of wind direction in the cockroach giant interneurons Adi Mizrahi and Frederic Libersat Zlotowski Center for Neurosciences and Department of Life Sciences, Ben- Gurion University of the Negev, Beer Sheva, Israel, 84105
APStracts 4:121N, 1997.
ABSTRACT
In this study, we have examined the possible role of cell-to-cell interactions in the localization processing of a wind stimulus by the cockroach cercal system. Such sensory processing is performed primarily by pairs of giant interneurons (GIs), a group of highly directional cells. We have studied possible interactions among these GIs by comparing the wind sensitivity of a given GI before and after removing another GI using photoablation. Testing various combinations of GI pairs did not reveal any supra-threshold interactions. This was true for all unilateral GI pairs on the left or right side as well as all the bilateral GI pairs (left and right homologues). In those experiments in which we were able to measure synaptic activity, we also did not observe sub-threshold interactions between the GIs. We conclude that the GIs code independently for a given wind direction without local GI-GI interactions. We discuss the possible implications of the absence of local interactions on information transfer in the first station of the escape circuit.

Received 18 June 1997; accepted in final form 23 June  1997.
APS Manuscript Number J217-7
Article publication pending J. Neurophysiol.
ISSN 1080-4757 Copyright 1997 The American Physiological Society.
Published in APStracts on 24 July 1997