Goal-directed selective attention and response competition monitoring: Evidence from unilateral parietal and anterior cingulate lesions

Competing visual stimuli lead to slower responses to targets. This response competition must be resolved before correct responses are executed. Neuroi maging suggests that response competition monitoring may be subserved by an integrated neural network including the anterior cingulate cortex (ACC). i n this study, I patient with a parietal lesion (Patient J.S.) and 1 with an ACC lesion (Patient G.M.) were presented with 2 flanker tasks; 1 required verbal identification of color targets, and the other required an opposite response to targets (e.g., see red and say "green"); a control group was al so tested. For controls, perceptually incongruent flankers interfered with the ability to inhibit prepotent responses to targets. Patient J.S. perform ed in a similar manner, even when flankers appeared in the neglected field. Patient G.M. demonstrated reduced interference effects for contralesional flankers. Results are discussed in terms of goal-directed selective attenti on and response competition monitoring.