Fig. 1.

The TMS procedure and its effect on speech production. During TMS trials, the coil was placed at a 45° angle, and electromyographic activity was recorded from the right first dorsal interosseus (FDI) and the right orbicularis oris (OO) muscle (A); the timing of repetitive TMS pulses relative in the experimental trial is depicted in B. C illustrates the effect of the TMS on speech production. The figure provides the waveform and spectrograms of two instances of the syllable pa. A first production is shown on the left, followed by four TMS pulses; the onset of the second pa syllable roughly coincides with the fourth pulse. TMS was associated with a marked perturbation in voicing and a delay in its onset (from 73 to 163 ms, for the first vs. second pa instance, respectively), along with a noticeable distortion in pitch (indicated by the dotted line).