From the Incomprehensible to the Partially Understood. An Update on Cognitive Bias Research and Metacognitive Training in Schizophrenia Psychosis

Metacognitive training (MCT) is a treatment approach aimed at correcting cognitive biases and reducing positive symptoms in nonaffective psychosis. Patients are taught to withhold overconfident and hasty decisions by becoming aware of the fallibility of human cognition and the advantages of balanced and particularly well-founded judgments for (social) decision-making. The present review reports on new findings on cognitive biases in psychosis. While a number of cognitive theories have been corroborated over the years, other assumptions have become more equivocal. We present new studies on the efficacy of MCT, as well as its individualized variant, termed MCT+. Although two recent meta-analyses arrived at somewhat different conclusions, they agree that group MCT exerts a small or small to medium effect. For individualized MCT, the effects are stronger. It seems that patients who fare the best in the group setting are those who already have at least partial insight. If these preconditions are not met, individualized therapy is deemed more beneficial. Dismantling studies are needed to elucidate core mechanisms of change. Recently, the program, which was initially directed at the reduction of positive symptoms only, has been expanded with modules addressing self-esteem and stigma as for many patients these domains represent a high treatment priority.