Aberrant network connectivity during error processing in patients with schizophrenia

Background Neuroimaging methods have pointed to deficits in the interaction of large-scale brain networks in patients with schizophrenia. Abnormal connectivity of the right anterior insula (AI), a central hub of the salience network, is frequently reported and may underlie patients' deficits in adaptive salience processing and cognitive control. While most previous studies used resting state approaches, we examined right AI interactions in a task-based fMRI study. Methods Patients with schizophrenia and healthy controls performed an adaptive version of the Eriksen Flanker task that was specifically designed to ensure a comparable number of errors between groups. Results We included 27 patients with schizophrenia and 27 healthy controls in our study. The between-groups comparison replicated the classic finding of reduced activation in the midcingulate cortex (MCC) in patients with schizophrenia during the commission of errors while controlling for confounding factors, such as task performance and error frequency, which have been neglected in many previous studies. Subsequent psychophysiological interaction analysis revealed aberrant functional connectivity (FC) between the right AI and regions in the inferior frontal gyrus and temporoparietal junction. Additionally, FC between the MCC and the dorsolateral prefrontal cortex was reduced. Limitations As we examined a sample of medicated patients, effects of antipsychotic medication may have influenced our results. Conclusion Overall, it appears that schizophrenia is associated with impairment of networks associated with detection of errors, refocusing of attention, superordinate guiding of cognitive control and their respective coordination.