Validity of chronometric TMS for probing the time-course of word production: a modified replication


In the present study, a modified replication of Schuhmann et al. (2012), we used chronometric TMS to probe the time-course of three brain regions during a picture naming task. The left inferior frontal gyrus (IFG), left posterior middle temporal gyrus (pMTG) and left posterior superior temporal gyrus (pSTG) were all separately stimulated in one of five time-windows (225, 300, 375, 450, 525ms) from picture onset. We found posterior temporal areas to be causally involved in picture naming in earlier time-windows, whereas all three regions appear to be involved in the later time-windows. However, chronometric TMS produces non-neuronal effects that may impact behavior, and furthermore, the time-course of any given process is a product of both the involved processing stages along with individual variation in the duration of each stage. We therefore extend previous work in the field by accounting for both individual variations in naming latencies and directly testing for non-neuronal effects of TMS. Our findings reveal that both factors influence behavioral outcomes at the group level. Underlining the importance of accounting for individual variations in naming latencies, especially for late processing stages closer to articulation and recognizing the presence of non-neuronal effects of TMS. The paper advances key considerations and avenues for future work using chronometric TMS to study overt production.

In: PsyArXiv
Adrian Jodzio
Adrian Jodzio
PhD candidate