Article

Mirror illusion therapy (mirror therapy) is based on the experimental
substrate of a visual illusion of active hand movement to excite ipsilateral
primary motor cortex (iM1). PURPOSE: We tested whether iM1 excitability could be
modulated by enabling or disabling vision of the active hand during mirror
therapy. METHOD: Motor cortical activations of healthy right-handed participants
were identified by magnetoencephalography. Participants performed voluntary index
finger extension of their dominant and non-dominant hands, separately, while
viewing mirror reflection images of their active hand superimposed upon their
hidden inactive hand. This was performed either with vision of the active hand
(uncovered viewing condition) or without vision of the active hand (covered
viewing condition). RESULTS: In the covered viewing condition, the iM1could be
excited in all participants (n = 10) and this excitation did not differ whether
the active hand was the dominant or non-dominant hand. However, in the uncovered
viewing condition, dominant and non-dominant hands were able to excite iM1 only
in some participants (n = 4 and n = 7, respectively). Moreover, the participants'
responses to the illusion validation questionnaire revealed that the covered
viewing condition could cause clearer visual illusion for the active hand than
the uncovered viewing condition. CONCLUSION: Disabling vision of the active hand
during mirror therapy was more effective to excite iM1 responses by creating more
immersive visual illusion of the active hand.

Langue : ANGLAIS