Dysregulation within the Prefronto-Parietal Background-Monitoring Network in Schizophrenia

Abstract

Schizophrenia patients have difficulties in focusing their attention, when distracting information must be ignored. Although it is adaptive in some situations to monitor the background for potentially relevant changes to a certain degree, voluntary attentional processes seem to be more severely disrupted by distracting information in schizophrenia patients compared to healthy controls. Reorienting processes associated with the detection of potentially relevant information outside the current focus of attention have previously shown to activate a bilateral prefronto-parietal network. The aim of the current study was to investigate whether this network is dysregulated in schizophrenia patients using fMRI during the performance in a combined oddball-incongruence task, in which relevant processing must be shielded from distracting irrelevant salient or conflicting information. During the occurrence of both oddballs and incongruence patients exhibited an increased activation of the intraparietal cortex—a saliency sensitive part of the prefronto-parietal network associated with background-monitoring. As this hyperactivation was accompanied by an increased activation in the dopaminergic midbrain, the results of our study link the finding of a hyperactive salience sensitive cortical region to the finding of the hyperdopaminergic state in schizophrenia, supporting the predominant view of psychosis as a state of aberrant salience.