Fig. 4
Interference, but not deep brain stimulation (DBS), modulates time-domain evoked potentials (ERPs) in source space. a, b Grand mean topographic plots of a stimulus- and (b) response-locked ERP. Voltages in control and interference trials were normalized against their respective pre-trial baselines before averaging. c–f Source-localized time courses of current density attributable to the left dorsal anterior cingulate gyrus (dACC) label, shown locked either to MSIT presentation (c, e) or response (d, f), and for both the control/interference contrast (c, d) and DBS ON/OFF contrast (e, f). dACC is often identified as the putative generator of midline frontal negativity in conflict tasks. “IAPS”, “MSIT”, and “Resp” denote the IAPS image onset, MSIT number stimulus onset, and mean response time (RT), respectively. Shading around each line is standard error of the mean computed from 1000 bootstrap resamples. Gray bar in c indicates a significant cluster mass at p < 0.05, corrected via permutation testing, signifying a difference between conditions (based on coefficients of sliding multivariate regression) from 291 to 473 ms. This is the only cluster in this label that survived FDR correction for multi-label testing; no DBS effect survived. g Time course of significant effects in the stimulus-locked analysis, corresponding to gray shading in c. Interference and arousal were the only factors that significantly influenced ERP amplitude in any region, with Interference effects throughout the dorsal frontal midline. a/A anterior, d dorsal, I inferior, m/M medial, r rostral, S superior, CC cingulate cortex, FG frontal gyrus
