The effects of repetitive proprioceptive stimulation on corticomotor representation in intact and hemiplegic individuals.
OBJECTIVE
To determine the effects of a passive wrist movement intervention on cortical representation of forearm musculature.


METHODS
Transcranial magnetic stimulation was used to map cortical representation of a forearm flexor muscle in healthy individuals and in individuals following stroke before and immediately after a 30 min session of passive wrist movement.


RESULTS
In the healthy individuals, no changes in map area or map centre of gravity were noted after the intervention; however, map volume increased significantly across all subjects. In the stroke patient group there were no significant changes in any parameters following the intervention.


CONCLUSIONS
It is speculated that the enlargement in map volume following the passive movement intervention arose through a heightened synaptic efficacy of the corticospinal pathway in response to the increase in afferent information. Short-term proprioceptive stimulation can induce alterations in corticomotor excitability in the target musculature.


CONCLUSIONS
These findings provide a potential neural substrate to account for alterations in motor and sensory function in stroke patients in response to long-term passive movement interventions.
Department of Sport and Exercise Science, Human Motor Control Laboratory, University of Auckland, Auckland, New Zealand. g-lewis3@northwestern.edu
Gwyn N
GN
Lewis
Winston D
WD
Byblow
D000368:Aged; D000369:Aged, 80 and over; D001931:Brain Mapping; D004558:Electric Stimulation; D005260:Female; D018466:Gravity Sensing / Q000502:physiology; D006429:Hemiplegia / Q000503:physiopathology*; D006801:Humans; D008280:Magnetics; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000502:physiology* / Q000503:physiopathology*; D009473:Neuronal Plasticity / Q000502:physiology; D011434:Proprioception / Q000502:physiology*; D020521:Stroke / Q000503:physiopathology