Article

Clinical assessment of motor imagery after stroke.

Department of Rehabilitation, Laval University, Quebec City, Quebec, Canada.
Neurorehabilitation and neural repair (impact factor: 4.49). 04/2008; 22(4):330-40. DOI:10.1177/1545968307313499
Source: PubMed

ABSTRACT The aim of this study was to investigate: (1) the effects of a stroke on motor imagery vividness as measured by the Kinesthetic and Visual Imagery Questionnaire (KVIQ-20); (2) the influence of the lesion side; and (3) the symmetry of motor imagery.
Thirty-two persons who had sustained a stroke, in the right (n = 19) or left (n = 13) cerebral hemisphere, and 32 age-matched healthy persons participated. The KVIQ-20 assesses on a 5-point ordinal scale the clarity of the image (visual scale) and the intensity of the sensations (kinesthetic scale) that the subjects are able to imagine from the first-person perspective.
In both groups, the visual scores were higher (P = .0001) than the kinesthetic scores and there was no group difference. Likewise, visual scores remained higher than kinesthetic scores irrespective of the lesion side. The visual scores poststroke were higher (P = .001) when imagining upper limb movements on the unaffected side than those on the affected side. When focusing on the lower limb only, however, the kinesthetic scores were higher (P = .001) when imagining movements of the unaffected compared to those on the affected side.
The vividness of motor imagery poststroke remains similar to that of age-matched healthy persons and is not affected by the side of the lesion. However, after stroke motor imagery is not symmetrical and motor imagery vividness is better when imagining movements on the unaffected than on the affected side, indicating an overestimation possibly related to a hemispheric imbalance or a recalibration of motor imagery perception.

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Keywords

32 age-matched healthy persons
 
5-point ordinal scale
 
age-matched healthy persons
 
first-person perspective
 
group difference
 
hemispheric imbalance
 
imagining movements
 
imagining upper limb movements
 
Kinesthetic
 
kinesthetic scale
 
kinesthetic scores
 
KVIQ-20 assesses
 
lesion side
 
motor imagery
 
motor imagery perception
 
motor imagery poststroke
 
motor imagery vividness
 
stroke motor imagery
 
Visual Imagery Questionnaire
 
visual scores poststroke
 

Francine Malouin