Article

OBJECTIVE: To identify adaptive changes within the motor network for internally
and externally paced finger movements in the acute and chronic phase after
ischemic stroke. DESIGN: A functional magnetic resonance imaging study of
internally and externally paced thumb-index-finger opposition 4 to 7 days and 3
months after stroke and in healthy controls. Images were compared within and
between groups, with the actual number of movements as regressors.
Stroke Unit, University Hospital. PARTICIPANTS: Twelve patients with mild to
moderate acute ischemic stroke and 15 controls (N=27). INTERVENTION: Stroke unit
treatment focused on very early rehabilitation, followed by early supported
discharge service. MAIN OUTCOME MEASURE: Differences in brain activation between
patients and controls and between the tasks. RESULTS: Patients showed significant
improvement in hand function at follow-up. Brain activity related to internally
paced finger movements normalized with time. For the externally paced, accurate
timing task, brain activity in the chronic phase differed from that seen in the
controls despite successful recovery of hand function. In comparing the
externally and internally paced tasks, a trend toward recruiting a
premotor-parietal-striatal network was found in patients in the chronic phase,
whereas controls had increased activation of a sensorimotor network consisting of
primary motor cortex, supplementary motor cortex, superior parietal lobe,
thalamus, and cerebellum. CONCLUSIONS: After ischemic stroke, brain activity
subserving an internally paced motor task normalized with time, whereas motor
activity in response to an externally paced task became dependent on a premotor
network. These findings underscore the importance of task-specific training in
the rehabilitation of stroke patients. In the future, physiotherapists should
evaluate the possibility of enhancing the recovery of a more efficient network
for externally paced tasks.
CI - Copyright (c) 2010 American Congress of Rehabilitation Medicine. Published by
Elsevier Inc. All rights reserved.

Langue : ANGLAIS