Effort-reward imbalance (ERI) is the ability to experience an imbalance between high effort and low reward, i.e., when one perceives that he/she is exerting more effort but receiving disproportionately less reward. Studies suggest that people with high levels of schizotypal traits are more likely to experience ERI than those with low levels of schizotypal traits, i.e., when an individual perceives that there are disproportionately fewer rewards than the effort expended. ERI is considered to be one of the important traits that characterizes people with negative rather than positive schizotypal traits.

Drs. HUANG Jia and Raymond Chan from the Institute of Psychology of the Chinese Academy of Sciences and their collaborators demonstrated that negative schizotypal traits had a significant negative moderating effect on the relationship between ERI and reward motivation, whereas positive and disorganized schizotypal traits had significant positive moderating effects.

They found that ERI correlated with reduced grey matter volume reduction and altered resting-state functional connectivity in people with high levels of negative schizotypal traits. However, it is unclear whether reward motivation adaptively changes with external effort/reward ratio, and what resting-state functional connectivity (rsFC) is associated with this change in people with negative schizotypal traits.

The researchers used an rsFC design to further address such issue. They recruited 35 participants with high levels of negative schizotypal traits and 44 participants with low levels of negative schizotypal traits to undergo resting-state brain scans.

In addition, all participants also completed the reward motivation adaptation behavioral task, which specifically captured "wanting" and "liking" behaviors.

The results showed that participants with high levels of negative schizotypal traits significantly decreased wanting and liking in the effort > reward condition, but did not rebound as much as participants with low levels of negative schizotypal traits in the effort/reward condition.

This study was published in European Archives of Psychiatry and Clinical Neuroscience and it was supported by the Institute of Psychology, the Scientific Foundation of Institute of Psychology, and the Philip K. H. Wong Foundation.