Activity of the neostriatum neurons in monkeys during operant behavior

Abstract

Monkeys (Macaca nemestrina) were trained to perform an operant task which included the following stages: bimanual movement to a visible target in response to a start signal, selection of the left or right operating hand according to the visual conditioning signal, careful movement of the selected hand, movements of fingers of the same hand, and taking of a reward. The spike activity was recorded simultaneously from five or six neurons in the caudate nucleus (Cd) head. Most of the Cd neurons were activated during the taking of a reward, the analysis of conditioning signals, and visually controlled movements. It has been found that the same neuron of the Cd may be activated in different ways during different components of the behavioral program, depending on the complexity of the conditioning signals and the correct versus incorrect selection of an operating hand. It is concluded that the Cd neurons have no functional specialization and that they take part in mechanisms preceding a movement or accompanying it, but not correlating with the form of its realization.