Transcranial magnetic stimulation of the right temporoparietal junction and left angular gyrus does not alter sense of joint agency in musical rhythmic coordination task: A pilot study

The sense of agency (SoA) refers to the perception that one's actions are influential and that one assumes responsibility for their consequences. In coordinated joint actions, a sense of joint agency emerges, with interaction and cooperation being crucial for enhancing SoA. Prior research indicates that the right temporoparietal junction (rTPJ) is integral to monitoring social contexts of SoA, while the left angular gyrus (lAG) focuses on individual aspects of agency. This study examined the effects of repetitive transcranial magnetic stimulation (rTMS) on SoA and judgment of performance (JoP) in eighteen healthy young participants using a three-way crossover design that included inhibitory neurostimulation of the rTPJ, excitatory stimulation of the lAG, and a sham intervention on the Vertex. Participants completed musical tasks involving rhythmic coordination before and after neurostimulation, with self-reported scores for SoA and JoP collected via Likert scales, alongside performance metrics (action time error and number of errors) evaluated through software. While rTMS did not yield significant effects on SoA, JoP, or performance overall, notable correlations between these variables suggest that neurostimulation may influence the interrelations among them. These findings highlight the complexities of how neurostimulation impacts perceived agency and performance, warranting further exploration into their interconnected dynamics.Keywords: transcranial magnetic stimulation, right temporoparietal junction, left angular gyrus, sense of joint agency, musical rhythmic coordination, joint action