Deficits in visual cognition and attention following bilateral anterior cingulotomy.

A series of eight tests of visual cognitive abilities was used to examine pre- to post-operative performance changes in a patient receiving bilateral anterior cingulotomy. Compared with a set of eight matched control participants, post-operatively, the patient exhibited deficits in (a) the ability to sequence novel cognitive operations required to generate multipart images or rotate perceptual stimuli; (b) the ability to search for, select, and compare images of objects when the instructions did not specify precisely which objects should be visualized; and, (c) the ability to select a controlled and unpracticed response over an automatic one. Other imagery and cognitive tasks were not affected. Results are consistent with the hypothesis that anterior cingulate cortex is a component of an executive control system. One of the anterior cingulate's roles may be to monitor on-line processing and signal the motivational significance of current actions or cognitions.