A series of eight tests of visual cognitive abilities was used to examine p
re- to post-operative performance changes in a patient receiving bilateral
anterior cingulotomy. Compared with a set of eight matched control particip
ants, post-operatively, the patient exhibited deficits in (a) the ability t
o sequence novel cognitive operations required to generate multipart images
or rotate perceptual stimuli; (b) the ability to search for, select, and c
ompare images of objects when the instructions did not specify precisely wh
ich objects should be visualized: and, (c) the ability to select a controll
ed and unpracticed response over an automatic one. Other imagery and cognit
ive tasks Mere not affected. Results are consistent with the hypothesis tha
t 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.
(C) 2001 Elsevier Science Ltd. All rights reserved.