Clinical Assessment of Motor Imagery After Stroke

Department of Rehabilitation, Laval University, Quebec City, Quebec, Canada.
Neurorehabilitation and neural repair (Impact Factor: 3.98). 04/2008; 22(4):330-40. DOI: 10.1177/1545968307313499
Source: PubMed


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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Available from: Julien Doyon, Aug 04, 2014
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    • "Motor imagery ability was assessed with the Kinesthetic and Visual Imagery Questionnaire (KVIQ – Malouin et al., 2007) in all participants. Individual SCI participant characteristics are summarized in Table 1 "

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    • "Selecting the subject-specific channels was especially important for stroke patients whose motor imagery were not symmetrical for the unaffected and affected sides (Malouin et al., 2008). A total of 9 frequency bands from 4 Hz to 36 Hz covering theta, mu (alpha), beta and low gamma frequency rhythms were employed to filter the EEG signal, which were generally employed for the detection of motor imagery of limb movements (Ramoser et al., 2000; Ang et al., 2011; Arvaneh et al., 2011; Blankertz et al., 2008; Lotte and Guan, 2011). "
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    • "This has been taken as evidence that the mental and actual temporal organization of movements share (at least in part) the same planning mechanisms [Decety and Michel, 1989]. Mental chronometry is thus regarded as a reliable method to evaluate individuals' MI ability [Guillot and Collet, 2005; Malouin et al., 2008a,b]. "
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