Open AccessIntermittent theta burst stimulation over right somatosensory larynx cortex enhances vocal pitch‐regulation in nonsingers
Author(s) -
Finkel Sebastian,
Veit Ralf,
Lotze Martin,
Friberg Anders,
Vuust Peter,
Soekadar Surjo,
Birbaumer Niels,
Kleber Boris
Publication year - 2019
Publication title -
human brain mapping
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.005
H-Index - 191
eISSN - 1097-0193
pISSN - 1065-9471
DOI - 10.1002/hbm.24515
Subject(s) - singing , somatosensory system , larynx , auditory feedback , transcranial magnetic stimulation , psychology , stimulation , audiology , neuroscience , coactivation , proprioception , medicine , acoustics , electromyography , physics , anatomy
While the significance of auditory cortical regions for the development and maintenance of speech motor coordination is well established, the contribution of somatosensory brain areas to learned vocalizations such as singing is less well understood. To address these mechanisms, we applied intermittent theta burst stimulation (iTBS), a facilitatory repetitive transcranial magnetic stimulation (rTMS) protocol, over right somatosensory larynx cortex (S1) and a nonvocal dorsal S1 control area in participants without singing experience. A pitch‐matching singing task was performed before and after iTBS to assess corresponding effects on vocal pitch regulation. When participants could monitor auditory feedback from their own voice during singing (Experiment I), no difference in pitch‐matching performance was found between iTBS sessions. However, when auditory feedback was masked with noise (Experiment II), only larynx‐S1 iTBS enhanced pitch accuracy (50–250 ms after sound onset) and pitch stability (>250 ms after sound onset until the end). Results indicate that somatosensory feedback plays a dominant role in vocal pitch regulation when acoustic feedback is masked. The acoustic changes moreover suggest that right larynx‐S1 stimulation affected the preparation and involuntary regulation of vocal pitch accuracy, and that kinesthetic‐proprioceptive processes play a role in the voluntary control of pitch stability in nonsingers. Together, these data provide evidence for a causal involvement of right larynx‐S1 in vocal pitch regulation during singing.