Title
Imaging correlates of motor recovery from cerebral infarction and their physiological significance in well-recovered patients.
Abstract
We studied motor representation in well-recovered stroke patients. Eighteen right-handed stroke patients and eleven age-matched control subjects underwent functional Magnetic Resonance Imaging (fMRI) while performing unimanual index finger (abduction–adduction) and wrist movements (flexion–extension) using their recovered and non-affected hand. A subset of these patients underwent Transcranial Magnetic Stimulation (TMS) to elicit motor evoked potentials (MEP) in the first dorsal interosseous muscle of both hands. Imaging results suggest that good recovery utilizes both ipsi- and contralesional resources, although results differ for wrist and index finger movements. Wrist movements of the recovered arm resulted in significantly greater activation of the contralateral (lesional) and ipsilateral (contralesional) primary sensorimotor cortex (SM1), while comparing patients to control subjects performing the same task. In contrast, recovered index finger movements recruited a larger motor network, including the contralateral SM1, Supplementary Motor Area (SMA) and cerebellum when patients were compared to control subjects. TMS of the lesional hemisphere but not of the contralesional hemisphere induced MEPs in the recovered hand. TMS parameters also revealed greater transcallosal inhibition, from the contralesional to the lesional hemisphere than in the reverse direction. Disinhibition of the contralesional hemisphere observed in a subgroup of our patients suggests persistent alterations in intracortical and transcallosal (interhemispheric) interactions, despite complete functional recovery.
Year
DOI
Venue
2007
10.1016/j.neuroimage.2006.09.010
NeuroImage
Keywords
Field
DocType
motor skills,magnetic resonance imaging,indexation
Anatomy,Index finger,Wrist,Transcranial magnetic stimulation,Functional magnetic resonance imaging,Motor skill,Cognitive psychology,Psychology,Cerebral infarction,Supplementary motor area,Physical medicine and rehabilitation,Magnetic resonance imaging
Journal
Volume
Issue
ISSN
34
1
1053-8119
Citations 
PageRank 
References 
5
0.54
6
Authors
6
Name
Order
Citations
PageRank
Dinesh G. Nair150.54
S Hutchinson2458.39
Felipe Fregni3306.20
Michael Alexander450.54
A Pascual-Leone5468.78
Gottfried Schlaug6273.87