Repetitive training of a synchronised movement induces short-term plastic changes in the human primary somatosensory cortex

The aim of our study was to assess possible short-term plastic ch an ges-in the human primary somatosensory cortex (S1) induced by a repetitive synchr onised movement of the right thumb and shoulder. We therefore performed a s ource localisation of somatosensory evoked potentials after median nerve st imulation in twelve healthy subjects before and after 1 h of motor training . We found a significant medial shift of the N20 dipole on the left hemisph ere after training, whereas the dipole location on the right hemisphere rem ained unchanged. However, no significant correlation was seen between the d ipole shift and the improvement in motor performance. We conclude that repe titive synchronised movements are able to induce plastic changes in the con tralateral S1, which might be mainly due to the synchronised proprioceptive input. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.