Format

Send to

Choose Destination
J Neurophysiol. 2002 Dec;88(6):3498-517.

Single-unit activity related to bimanual arm movements in the primary and supplementary motor cortices.

Author information

1
Department of Physiology and the Center for Neural Computation, The Hebrew University, Hadassah Medical School, Jerusalem 91120, Israel. opher@bme.jhu.edu

Abstract

Single units were recorded from the primary motor (MI) and supplementary motor (SMA) areas of Rhesus monkeys performing one-arm (unimanual) and two-arm (bimanual) proximal reaching tasks. During execution of the bimanual movements, the task related activity of about one-half the neurons in each area (MI: 129/232, SMA: 107/206) differed from the activity during similar displacements of one arm while the other was stationary. The bulk of this "bimanual-related" activity could not be explained by any linear combination of activities during unimanual reaching or by differences in kinematics or recorded EMG activity. The bimanual-related activity was relatively insensitive to trial-to-trial variations in muscular activity or arm kinematics. For example, trials where bimanual arm movements differed the most from their unimanual controls did not correspond to the ones where the largest bimanual neural effects were observed. Cortical localization established by using a mixture of surface landmarks, electromyographic recordings, microstimulation, and sensory testing suggests that the recorded neurons were not limited to areas specifically involved with postural muscles. By rejecting this range of alternative explanations, we conclude that neural activity in MI as well as SMA can reflect specialized cortical processing associated with bimanual movements.

PMID:
12466464
DOI:
10.1152/jn.00335.2001
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Atypon
Loading ...
Support Center