Quenching the Groove: Inhibition of left SMA with cTBS Disrupts the Urge to Move to Music

Poster Session D - Monday, April 15, 2024, 8:00 – 10:00 am EDT, Sheraton Hall ABC

Connor Spiech^1,2 (connorspiech@gmail.com), Virginia Penhune^1,2; ¹Department of Psychology, Concordia University, ²BRAMS - International Laboratory for Brain, Music and Sound Research

The pleasurable urge to move to music (termed “groove” by music psychologists) has been shown to be greatest for music with moderately complex rhythms. This is thought to occur because temporal predictions from the motor system reinforce our perception of the beat when there is a balance between expectation and surprise. The supplementary motor area (SMA) has been identified as the potential origin of these temporal predictions based on both neuroimaging and computational modeling studies. Thus, to causally test the role of the SMA in the experience of groove, we used transcranial magnetic stimulation to disrupt activity in this region while non-musicians listened to and rated clips of commercially recorded music that varied in rhythmic complexity and perceived groove. Continuous theta burst stimulation was delivered over left SMA and a control location in primary visual cortex (V1) at 80% of participants’ active motor or phosphene threshold. Following stimulation over left SMA, but not V1, participants preferred to move to music with low rather than to moderate rhythmic complexity while pleasure ratings were unaffected. These preliminary results suggest that the left SMA maintains temporal predictions, perhaps by weighting the precisions of prediction errors. Therefore, when left SMA function is inhibited, participants can no longer covertly update their model of the beat in simpler rhythms and thus feel compelled to use movement to reinforce the model instead. In summary, these findings provide causal evidence that the SMA plays a critical role in generating temporal predictions for embodied rhythm processing.

Topic Area: PERCEPTION & ACTION: Motor control