The reality of virtual limbs: does mirror technique for hand has functional consequences for the motor output?

Abstract

Motor imagery was proven to excite the motor cortex as actual action execution. Therefore, motor imagery training was suggested as a method of facilitating the rehabilitation of the paretic limbs following stroke. Objective. To investigate whether motor imagery brings objectively measurable effects on the motor behaviour, and whether these effects can be enhanced by the application of the mirror technique. Three experiments were conducted involving 32 neurologically healthy participants, with strong right-handedness. Motor imagery simulation of the bimanual movement induced similar changes in terms of temporal precision as overt motor execution. The mid-sagittal mirror technique increased the subjective kinaesthetic and visual vividness of the motor imagery. The source of the observed changes in motor parameters under motor imagery conditions was identified to be different during bimanual conditions. Further investigations need to be conducted to examine the mechanisms underlying observed patterns of results.