Neural correlates of speech recovery after intra-oral surgery
Résumé
This study aims at better understanding the reorganization process at the cortical and subcortical levels underlying the functional recovery of speech after mouth surgery (i.e. carcinologic resection of mobile tongue and/or mouth floor). In order to determine how the brain integrates new relationships between motor commands, auditory and orosensory feedbacks and new inter-articulators coordination, we designed a longitudinal sparse-sampling fMRI study based on orofacial, vocalic and syllabic production tasks on 10 patients one week before, one month and three months after surgery. Before surgery, less neural activity was observed in sensorimotor regions in patients compared to healthy subjects while, one month after intra-oral resection, an increase of activity was observed in the supplementary motor area and in the cingulate cortex (both involved in selection and initiation process suggesting more competitive mechanisms between motor strategies after surgery). Additional patients are still currently recruited and we expect the speech recovery process to be also associated with significant activity changes in the cerebellum in relation with changes in motor plant.