The influence of STN-DBS on midfrontal theta power and antisaccade latency
In the single-trial EEG analysis, higher theta activity during the late preparatory phase precited longer antisaccade latency in the off-DBS state. Consistent with this finding, theta activity has been associated with a slowing of the upcoming response in a variety of cognitively demanding tasks (Conversely, the trial-by-trial correlation analysis revealed an inversion of the relationship between midfrontal theta power and antisaccade latency with 130 Hz-DBS. This finding is in line with results from Cavanagh and colleagues who described the same stimulation-induced inversion of the relationship between midfrontal theta and response times during high conflict trials in a decision-making task (In the model of striatal action selection, the STN is pivotal for inhibiting prepotent actions under conflict (Yet, the probability of an error was not altered with 130 Hz-DBS, and thus, the reversed relationship between midfrontal theta and antisaccade latency was not linked to impulsive actions on a behavioral level in our study. Indeed, some studies also reported higher midfrontal theta power scaling with speeding of responses in healthy individuals under no influence of any intervention like DBS (