Microstimulation of monkey dorsolateral prefrontal cortex impairs antisaccade performance

The dorsolateral prefrontal cortex (DLPFC) has been implicated in various cognitive functions, including response suppression. This function is frequently probed with the antisaccade task, which requires suppression of the automatic tendency to look toward a flashed peripheral stimulus (prosaccade), and instead generate a voluntary saccade to the mirror location. To test whether activity in the DLPFC is causally linked to antisaccade performance, we applied electrical microstimulation to sites in the DLPFC of two monkeys, while they performed randomly interleaved pro- and antisaccade trials. Microstimulation resulted in significantly longer saccadic reaction times for ipsilaterally directed prosaccades and antisaccades, and increased the error rate on ipsilateral antisaccade trials. These findings provide causal evidence that activity in the DLPFC influences saccadic eye movements.