Frontal and cerebellar contribution to pitch and rhythm processing: a TMS study

Abstract

Abstract Music represents a salient stimulus for the brain with two key features: pitch and rhythm. Few data are available on cognitive analysis of music listening in musically naïve healthy participants. Beyond auditory cortices, neuroimaging data showed the involvement of prefrontal cortex in pitch and of cerebellum in rhythm. The present study is aimed at investigating the role of prefrontal and cerebellar cortices in both pitch and rhythm processing. The performance of fifteen participants without musical expertise was investigated in a listening comparative task. The task required to decide whether two eight-element melodic sequences were equal or different according to pitch or rhythm characteristics. Before the task, we applied a protocol of continuous theta burst transcranial magnetic stimulation interfering with the activity of the left cerebellar hemisphere (lCb), right inferior frontal gyrus (rIFG), or vertex (Cz-control site), in a within cross-over design. Our results showed that participants were more accurate in pitch than rhythm tasks. Importantly, following rIFG or lCb relative to Cz stimulations, the reaction times were slower and with no difference in both tasks. Notably, no lateralized motor stimulation effect was observed. The present findings point to the role of the fronto-cerebellar network in music processing with a single mechanism for both pitch and rhythm patterns.