Functional recovery following lesions of the primary somatosensory area : a study of the compensatory mechanisms

During along tithe, lesions of the primary somatosensory area (S I) were considered as generating severe and definitive neurological seguelae. However, recent reports described a recovery following stroke and resective surgeries (for epilepsy or tumor). On the basis of these observations, of experimentations in animals,, arid of studies of the (re)organization of eloquent areas in mart using new methods of functional mapping, brain plasticity phenomena underlying the recovery were analyzed. They seems to implicate the recruitment of local areas (sensory redundancies within S I), regional areas (primary motor area, secondary somatosensory area, posterior parietal cortex, insula), controlateral eloquent regions, and even learning of new compensatory strategies. Such data could allow its to extend surgical indications of resection of lesions located within S I. An improvement of our knowledge of these functional reshaping phenomena (unmasking of latent networks and/or participation of eloquent homologous and/or sprouting) and then their prediction remains mandatory, with the goal to optimize the surgical preplanning in functional regions, taking account of the individual dynamic spatio-temporal cortical organization. This better knowledge seems to be obtained by studying the correlations between pre- and post-operative functional neuroimaging (fMRI, MEG) data, and the intraoperative functional mapping results.