Psychotic disorders, dopaminergic agents and EEG/MEG resting-state functional connectivity: A systematic review

Abstract

Both dysconnectivity and dopamine hypotheses are two well researched pathophysiological models of psychosis. However, little is known about the direct effect of dopamine dysregulation on brain functional connectivity in psychotic disorders, specifically through the modulation of antipsychotic medication. In this systematic review, we summarize the existing evidence of dopaminergic effects on electro- and magnetoencephalographic (EEG/MEG) resting-state brain functional connectivity with sensor- as well as source-level measures. A wide heterogeneity of results was found amongst the 20 included studies with increased and decreased functional connectivity in medicated psychosis patients vs. healthy controls in widespread brain areas across all frequency bands. No systematic difference in results were seen between studies with medicated and those with unmedicated psychosis patients and very few studies directly investigated the effect of dopamine agents with a pre-post design. The reported evidence clearly calls for longitudinal EEG and MEG studies with large participant samples to directly explore the antipsychotic medication effect on neural networks over time during illness progression and to ultimately support the development of new treatment strategies.