Published online Jun 28, 2014. doi: 10.4329/wjr.v6.i6.261
Revised: February 7, 2014
Accepted: May 16, 2014
Published online: June 28, 2014
To provide a systematic review of scientific literature on functional magnetic resonance imaging (fMRI) studies on sustained attention in psychosis. We searched PubMed to identify fMRI studies pertaining sustained attention in both affective and non-affective psychosis. Only studies conducted on adult patients using a sustained attention task during fMRI scanning were included in the final review. The search was conducted on September 10th, 2013. 15 fMRI studies met our inclusion criteria: 12 studies were focused on Schizophrenia and 3 on Bipolar Disorder Type I (BDI). Only half of the Schizophrenia studies and two of the BDI studies reported behavioral abnormalities, but all of them evidenced significant functional differences in brain regions related to the sustained attention system. Altered functioning of the insula was found in both Schizophrenia and BDI, and therefore proposed as a candidate trait marker for psychosis in general. On the other hand, other brain regions were differently impaired in affective and non-affective psychosis: alterations of cingulate cortex and thalamus seemed to be more common in Schizophrenia and amygdala dysfunctions in BDI. Neural correlates of sustained attention seem to be of great interest in the study of psychosis, highlighting differences and similarities between Schizophrenia and BDI.
Core tip: In the present paper, we systematically reviewed functional magnetic resonance imaging studies investigating sustained attention in affective and non-affective psychosis. We found that differences between cases (patients, unaffected relatives of psychotic probands) and controls in terms of functional activation of sustained attention system structures were detectable even when the groups performed comparably. In particular, the insular cortex seems to be a trait marker for psychosis in general, whereas other regions (thalamus, cingulate cortex, amygdala) seem to be differently impaired in affective and non-affective psychosis.