当前位置： SCI文献检索 > JOURNAL OF NEUROPHYSIOLOGY期刊下所有文献 > Sequential activation of motor cortical neurons contributes to intralimb coordination during reaching in the cat by modulating muscle synergies.

Sequential activation of motor cortical neurons contributes to intralimb coordination during reaching in the cat by modulating muscle synergies.

Abstract：

:We examined the contribution of the motor cortex to the control of intralimb coordination during reaching in the standing cat. We recorded the activity of 151 pyramidal tract neurons (PTNs) in the forelimb representation of three cats during a task in which the cat reached forward from a standing position to press a lever. We simultaneously recorded the activity of muscles in the contralateral forelimb acting around each of the major joints. Cell activity was recorded with and without the presence of an obstacle requiring a modification of limb trajectory. The majority of the PTNs (134/151, 89%) modulated their discharge activity at some period of the reach while 84/151 (56%) exhibited a significant peak or trough of activity as the limb was transported from its initial position to the lever. These phasic changes of activity were distributed sequentially throughout the transport phase. A cluster analysis of muscle activity in two of the cats showed the presence of five muscle synergies during this transport period. One of the synergies was related to the lift of the paw from the support surface, two to flexion of the limb and dorsiflexion of the paw, one to preparation for contact with the lever, and one to the transport of the entire limb forward; a sixth synergy was activated during the lever press. An analysis of the phase of cell activity with respect to the phase of activity of muscles selected to represent each of these synergies showed that different populations of PTNs were activated sequentially and coincidentally with each synergy. We suggest that this sequential activation of populations of PTNs is compatible with a contribution to the initiation and modulation of functionally distinct groups of synergistic muscles and ultimately serves to ensure the appropriate multiarticular, intralimb coordination of the limb during reaching.

journal_name

J Neurophysiol

journal_title

Journal of neurophysiology

authors

Yakovenko S,Krouchev N,Drew T

doi

10.1152/jn.00469.2010

subject

Has Abstract

pub_date

2011-01-01 00:00:00

pages

388-409

issue

eissn

0022-3077

issn

1522-1598

pii

jn.00469.2010

journal_volume

105

pub_type

杂志文章

在线工具

Sequential activation of motor cortical neurons contributes to intralimb coordination during reaching in the cat by modulating muscle synergies.