Fig. 1.

Task. (A) Patients performed an arrowed version of the Eriksen Flanker task, where they indicated the direction of a middle arrow flanker by either low (<<<<<) or high (>><>>) conflict arrows. A fixation dot was present throughout the entire experiment, but changed from white to gray 500 ms before the arrows were shown. Inset shows that subjects had slower reaction times and higher error rates during the high conflict trials. Group average ± SEM is shown. ** denotes p < 0.01, *** denotes p < 0.001. (B) Consistent with previous STN recordings, the onset of the arrows elicited a decrease in beta power and an increase in low frequency, including theta, power. Our subsequent analysis focused on the band passed theta (4–8 Hz) power (bottom). The group average across all trials and all STNs is shown for top and bottom panels, with shaded region in bottom panel denoting SEM across STNs.