Spatiotemporal neuromagnetic activities during pitch processing in musicians

摘要

Although the spatial distribution of neural subsystems involved in music processing has been elucidated by recent neuroimaging studies, little is known about the temporal profile of such neural activities. In this study, Spatiotemporal neuromagnetic activities during pitch processing in a musical context were investigated using a cross-modal pitch-matching task, which required subjects to find infrequent pitch errors implanted in heard performance while sight-reading its musical score. Eight right-handed musicians and eight right-handed non-musicians participated in this study. Neuromagnetic responses to each tone onset were recorded using VectorView~(? (Neuromag, Helsinki, Finland). The source localization was estimated by minimum current estimates (MCE) algorithm and was verified by a multiple-current-dipole model. Although every subject showed magnetic components, M50, M100 and M200 in both erroneous and correct conditions, significant amplitude difference between these two conditions was detected only in musicians. Incongruent condition activated spatiotemporally distributed brain regions, including not only superior temporal gyrus but also other areas; the middle temporal, inferior temporal, inferior frontal, dorsolateral prefrontal cortex, inferior parietal lobule and sensorimotor cortex were activated in musicians. On the contrary, activated areas were limited in the vicinity of the auditory cortex in both conditions in non-musicians. Our findings suggest musicians' multiple strategies of pitch processing.