Article

Decreased conflict- and error-related activity in the anterior cingulate cortex in subjects with schizophrenia

Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
American Journal of Psychiatry (Impact Factor: 13.56). 11/2005; 162(10):1833-9. DOI: 10.1176/appi.ajp.162.10.1833
Source: PubMed

ABSTRACT People with schizophrenia have exhibited reduced functional activity in the anterior cingulate cortex during the performance of many types of cognitive tasks and during the commission of errors. According to conflict theory, the anterior cingulate cortex is involved in the monitoring of response conflict, acting as a signal for a need for greater cognitive control. This study examined whether impaired conflict monitoring in people with schizophrenia could underlie reduced anterior cingulate activity during both correct task performance and error-related activity.
Functional activity in the anterior cingulate of 13 schizophrenia patients and 13 healthy comparison subjects was investigated by using event-related fMRI and a Stroop task that allowed simultaneous examination of activity during both conflict (incongruent trials) and error (commission of error trials).
In the presence of comparable reaction time measures for conflict as well as comparable error rates, the schizophrenia subjects showed both decreased conflict- and error-related activity in the same region of the anterior cingulate cortex. Moreover, those with schizophrenia did not exhibit significant post-conflict or post-error behavioral adjustments.
Concurrently reduced conflict- and error-related activity in the anterior cingulate cortex along with reduced trial-to-trial adjustments in performance has not previously been reported in schizophrenia. The current results suggest that impaired conflict monitoring by the anterior cingulate cortex might play an important role in contributing to cognitive control deficits in patients with schizophrenia.

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    • "Structural magnetic resonance imaging (MRI) and neuropathological findings demonstrate gray matter reductions of the ACC in patients with psychosis, occurring already prior to its onset and, eventually, progressing with illness duration (Fornito et al., 2009). In functional MRI (fMRI) studies, patients with schizophrenia showed reduced conflict-(Snitz et al., 2005) as well as errorrelated activity in the ACC (see Melcher et al., 2008, for a review; Carter et al., 2001; Alain et al., 2002; Kerns et al., 2005), which may normalize upon administration of antipsychotic medications (Snitz et al., 2005; Adams and David, 2007). Studies reported hypo-activation in patients only for the rostral division of the ACC during Stroop (Carter et al., 1997), Go/NoGo (Laurens et al., 2003), oddball (Liddle et al., 2006), or emotion recognition tasks (Habel et al., 2010). "
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