Effects of a rostral motor cortex lesion on primary motor cortex hand representation topography in primates.
BACKGROUND
Small lesions to rostral versus caudal portions of the hand representation in the primary motor cortex (M1) produce different behavioral deficits. The goal of the present study was to determine if rehabilitative training has similar effects on functional topography of the spared M1 after rostral versus previously reported caudal M1 lesions.


METHODS
Following a lesion to the rostral M1 hand area, monkeys were trained for 1 h/day for 30 days to retrieve food pellets from small wells using their impaired hand. Electrophysiological maps of the M1 were derived in anesthetized monkeys before infarct and after rehabilitative training using intracortical microstimulation.


RESULTS
After a lesion to the rostral M1 and rehabilitative training, the size of the spared hand representation decreased 1.2%. This change is not statistically different from the 9% increase seen after caudal M1 lesion and rehabilitative training (P > 0.2).


CONCLUSIONS
Postlesion training spares peri-infarct hand area regardless of whether the lesion is in the rostral or caudal M1.
Friel
Kathleen M
KM
Department of Molecular and Integrative Physiology, Landon Center on Aging, and Smith Mental Retardation Research Center, University of Kansas Medical Center, Kansas City, KS, USA. kf2105@columbia.edu
Barbay
Scott
S
Frost
Shawn B
SB
Plautz
Erik J
EJ
Stowe
Ann M
AM
Dancause
Numa
N
Zoubina
Elena V
EV
Nudo
Randolph J
RJ
D000818:Animals; D032763:Behavior Control; D002545:Brain Ischemia / Q000473:pathology / Q000503:physiopathology* / Q000534:rehabilitation*; D001931:Brain Mapping; D005260:Female; D006225:Hand / Q000503:physiopathology*; D008297:Male; D009043:Motor Activity / Q000502:physiology; D009044:Motor Cortex / Q000503:physiopathology*; D012149:Restraint, Physical; D012453:Saimiri; D013997:Time Factors