Abstract
The authors tested a patient suffering from a circumscribed lesion of the right frontal operculum (FO) in 3 experiments of visual attention involving spatial orienting, maintenance of task-relevant priorities, and control of interference from new and old task-irrelevant items. The authors found that spatial orienting and active maintenance of priorities were intact, but there were difficulties in controlling interference from new and old irrelevant items. These results suggest that the FO is necessary for the direct control of interference, but its lesion alone is not enough to disturb spatial orienting processes or active maintenance of task priorities. The authors discuss the results in light of a hybrid cognitive model of attention.