NEURAL ACTIVITY RELATED TO REACHING AND GRASPING IN ROSTRAL AND CAUDAL REGIONS OF RAT MOTOR CORTEX

The objective of this study was to assess the relation of motor cortic al neural activity in the rat to self-paced reach-to-grasp movements. Overall, around 40% of excitatory and 60% of inhibitory modulations in neuronal activity began prior to reach onset. These data are consiste nt with a role for rat motor cortex in the initiation and control of t he reaching movement. In addition, although the reach only lasted a sh ort time, 30% of excitations and inhibitions began while it was in pro gress. The existence of such modulations occurring during the reach is consistent with previous data showing activity of cortical neurons la te in the reach, and suggests a heavy involvement of cortical neurons in controlling the recently described, complex movements associated wi th grasping that are seen in the rat. These features were broadly simi lar in neurones from both the caudal and rostral subdivisions of rat m otor cortex. (C) 1998 Elsevier Science B.V. All rights reserved.