Effort-reward imbalance (ERI) is a psychological process that affects our goal-directed and motivational behaviour. It refers to an imbalance between high-effort commitment and low-reward outcome. It is believed that such an imbalance will be commonly observed in patients with schizophrenia spectrum disorders who are characterized by the presence of negative symptoms including reduced ability to approach reward, and to main goal setting.

Recent findings also suggest that individuals with high levels of schizotypal traits also share similar behavioural manifestations of schizophrenia patients. However, it is not clear whether ERI will be commonly exhibited in individuals with schizotypy and its underlying neural correlates.

Drs. HUANG Jia and Raymond Chan from the Institute of Psychology of the Chinese Academy of Sciences (CAS), together with their collaborators, have conducted a study to examine specifically the relationships between ERI, schizotypy and brain structures and functions.

They recruited 37 participants with high levels of schizotypy and 36 participants with low levels of schizotypy to undertake a brain scan to collect resting-state and voxel-based morphometric imaging data. All participants also completed a checklist to capture ERI. Their findings showed that participants with high levels of schizotypy were more likely to perceive ERI.

More interestingly, they found that the severity of ERI correlated significantly with grey matter volume reduction of the left pallidum and altered rsFC among the prefrontal, striatum and cerebellum in participants with high levels of schizotypy. Participants with low levels of schizotypy did not exhibit such a relationship.

Taken together, these findings suggest there is a correlation between ERI and grey matter volume reduction and altered resting-state functional connectivity in participants with high level of schizotypy.

This study is now published online on Mar. 11, 2021 in Cognitive Neuropsychiatry entitled "The effect of effort-reward imbalance on brain structure and resting-state functional connectivity in individuals with high levels of schizotypal traits."

This study was supported by grants from the National Key Research and Development Programme, the National Natural Science Foundation of China, the Beijing Training Project for Leading Talents in Science and Technology, and the CAS Key Laboratory of Mental Health of the Institute of Psychology.