Neuronal clusters in the primate motor cortex during interception of moving targets.

Full Abstract

Two rhesus monkeys were trained to intercept a moving target at a fixed location with a feedback cursor controlled by a 2-D manipulandum. The direction from which the target appeared, the time from the target onset to its arrival at the interception point, and the target acceleration were randomized for each trial, thus requiring the animal to adjust its movement according to the visual input on a trial-by-trial basis. The two animals adopted different strategies, similar to those identified previously in human subjects. Single-cell activity was recorded from the arm area of the primary motor cortex in these two animals, and the neurons were classified based on the temporal patterns in their activity, using a nonhierarchical cluster analysis. Results of this analysis revealed differences in the complexity and diversity of motor cortical activity between the two animals that paralleled those of behavioral strategies. Most clusters displayed activity closely related to the kinematics of hand movements. In addition, some clusters displayed patterns of activation that conveyed additional information necessary for successful performance of the task, such as the initial target velocity and the interval between successive submovements, suggesting that such information is represented in selective subpopulations of neurons in the primary motor cortex. These results also suggest that conversion of information about target motion into movement-related signals takes place in a broad network of cortical areas including the primary motor cortex.

Author information

Author/s: Lee, D (D); Port, N L (NL); Kruse, W (W); Georgopoulos, A P (AP);

Affiliation: Veteran Affairs Medical Center, Minneapolis, MN 55417, USA.

Grants: 1-PSMH48185 (Agency:NCHHSTP CDC HHS)

Journal and publication information

Publication Type: Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, Non-P.H.S.; Research Support, U.S. Gov't, P.H.S.

Journal: Journal of cognitive neuroscience (J Cogn Neurosci), published in United States. (Language: eng)

Reference: 2001-Apr; vol 13 (issue 3) : pp 319-31

Dates: Created 2001/05/23; Completed 2001/07/19; Revised 2007/11/14;

PMID: 11371310, status: MEDLINE (last retrieved date: 2/18/2009)

Sourced from the National Library of Medicine. Abstract text and other information may be subject to copyright.

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