An integrator-like circuit in cerebellar cortex

Abstract

Event Abstract Back to Event An integrator-like circuit in cerebellar cortex Reinoud Maex1* 1 University of Hertfordshire, Science and Technology Research Institute, United Kingdom The brain builds dynamic models of the body and the outside world in order to predict the consequences of stimuli and actions. Dynamic models require a component that mathematically integrates signals with respect to time. A well known example is the oculomotor integrator, which calculates eye position from eye velocity commands to counteract the elasticity forces that destabilize gaze direction. Many models for neural integration have been proposed, based on feedback excitation, lateral inhibition, or intrinsic neuronal nonlinearities. We here draw the attention to the presence of an integrator-like circuit in the cerebellar cortex, an organ thought to implement dynamic models. Our computer simulations of a model of the cerebellar cortex demonstrate that the output neurons, Purkinje cells, can integrate their parallel-fiber inputs. Their responses to pulse, step and sinewave stimuli are found to have components with time-constants greater than 10 seconds. Both neuronal and network mechanisms contribute. A bi-stability of the Purkinje cell dynamics (phenomenologically the transition to an ON state) generates a slow response tail following pulse stimulation, whose amplitude and time-constant strongly depend on the pre-stimulus baseline spike rate, vanishing at low and high rates. Reciprocal inhibition among the Purkinje cells via their recurrent axon collaterals further prolongs the slow response component to step and sinewave stimuli. This model explains how a fast circuit like the cerebellar cortex may learn the timing of slow processes. Modulation of the baseline spike rate by inhibitory synapses may be a mechanism of plasticty of the response time-course independently of the response amplitude. Keywords: computational neuroscience Conference: Bernstein Conference on Computational Neuroscience, Berlin, Germany, 27 Sep - 1 Oct, 2010. Presentation Type: Presentation Topic: Bernstein Conference on Computational Neuroscience Citation: Maex R (2010). An integrator-like circuit in cerebellar cortex. Front. Comput. Neurosci. Conference Abstract: Bernstein Conference on Computational Neuroscience. doi: 10.3389/conf.fncom.2010.51.00099 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 03 Sep 2010; Published Online: 23 Sep 2010. * Correspondence: Dr. Reinoud Maex, University of Hertfordshire, Science and Technology Research Institute, Hertfordshire, United Kingdom, r.maex1@herts.ac.uk Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Reinoud Maex Google Reinoud Maex Google Scholar Reinoud Maex PubMed Reinoud Maex Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.