Frontoparietal Activation With Preparation for Antisaccades

Abstract

Several current models hold that frontoparietal areas exert cognitive control by biasing task-relevant processing in other brain areas. Previous event-related functional magnetic resonance imaging (fMRI) studies have compared prosaccades and antisaccades, which require subjects to look toward or away from a flashed peripheral stimulus, respectively. These studies found greater activation for antisaccades in frontal and parietal regions at the ends of long (>or=6 s) preparatory periods preceding peripheral stimulus presentation. Event-related fMRI studies using short preparatory periods (<or=4 s) have not found such activation differences except in the frontal eye field. Here, we identified activation differences associated with short (1-s) preparatory periods by interleaving half trials among regular whole trials in a rapid fMRI design. On whole trials, a colored fixation dot instructed human subjects to make either a prosaccade toward or an antisaccade away from a peripheral visual stimulus. Half trials included only the instruction and not peripheral stimulus presentation or saccade generation. Nonetheless, half trials evoked stronger activation on antisaccades than on prosaccades in the frontal eye field (FEF), supplementary eye field (SEF), left dorsolateral prefrontal cortex (DLPFC), anterior cingulate cortex (ACC), intraparietal sulcus (IPS), and precuneus. Greater antisaccade response-related activation was found in FEF, SEF, IPS, and precuneus but not in DLPFC or ACC. These results demonstrate greater preparatory activation for antisaccades versus prosaccades in frontoparietal areas and suggest that prefrontal cortex and anterior cingulate cortex are more involved in presetting the saccade network for the antisaccade task than generating the actual antisaccade response.

Control of the superior colliculus by the lateral prefrontal cortex

“…Greater pre-stimulus activation in the frontal cortex on correct when compared with error trials has also been reported by an event-related potential study [25]. Recently, an electroencephalogram study reported a decrease in ongoing beta-power (20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30) in frontal cortex on error trials during the preparatory period on antisaccade trials [26]. In general, data from human imaging studies indicate that increased PFC activation, particularly of the region of the middle frontal gyrus, is associated with correct performance on the antisaccade task.…”

Stimulation of the Frontal Eye Field Reveals Persistent Effective Connectivity after Controlled Behavior

“…1 B). They were clustered at the coordinate (30,2,57) in the standard brain of the Montreal Neurological Institute (MNI), which corresponds to the FEF (Ford et al, 2005;Grosbras et al, 2005;Brown et al, 2007). In the control experiment, the procedure was as above with the exception that we delivered TMS to the postcentral gyrus (mean coordinate: 28, Ϫ42, 66), following the procedure of a previous TMS-EEG study (Taylor et al, 2007b).…”

A competitive integration model of exogenous and endogenous eye movements

“…This includes neurons that are active during fixation and neurons that seem to prepare for a saccade. As revealed with fMRI, preparation for an antisaccade activates DLPFC more strongly than any other brain region (Brown et al 2007). Neuropsychological evidence also suggests that this area plays an important role in the control of voluntary eye movements.…”