A neural mechanism of adaptive suppression of background signals arising from tail movements in the Gymnotid electrosensory system

To clarify the neuronal mechanism for adaptive suppression of background si gnals arising from a fish's own motion, we proposed a neural network model of electrosensory lateral-line lobe (ELL) including two types of descending pathways from the higher brain regions. The response properties of the mod el relating to the adaptive suppression of reafferent signals reproduced sy stematically the relevant results observed by Bastian under various conditi ons. The response properties are generated mainly by the dynamical variatio n in the strength of the synapse of apical dendrite receiving the descendin g signals, which depends quite sensitively on the relative timing of arriva l of descending signals and depolarization of apical dendrite. (C) 1999 Els evier Science B.V. All rights reserved.