Characterizing social motivation deficits in treatment‐resistant schizophrenia: Evidence from social incentive performance

AIM: The Treatment-Response-and-Resistance-in-Psychosis (TRRIP) criteria recognizes negative symptoms as defining features for treatment-resistant schizophrenia (TRS). Social motivation refers to the desire to pursue social reward (and to avoid social punishment). Impaired social motivation is related to negative symptoms but has seldom been studied in TRS patients. We aimed to characterize social motivation processing in TRS patients and examine the impacts of negative symptoms on social motivation processing. METHODS: We recruited 60 TRS patients, 60 remitted schizophrenia patients and 60 controls. In the Social Incentive Delay (SID) task, participants had to hit the targets within the response window to seek positive/neutral/negative social outcomes in emoji formats; and they also rated their emotions during the anticipation and receipt of social outcomes. Generalized-estimation-equation (GEE) models examined the impacts of TRS/remitted schizophrenia, negative symptoms, and the interaction between clinical-group-status and cue-valence on the SID performance, that is, hit-or-not, anticipatory pleasure, and consummatory pleasure. RESULTS: The interaction between TRS status and social reward/punishment significantly predicted anticipatory pleasure, implicating that TRS patients' anticipatory pleasure was less subject to social reward/punishment compared to controls. Moreover, the interaction between TRS and social reward significantly predicted consummatory pleasure, implicating that TRS patients' consummatory pleasure was less subject to social reward compared to controls. Negative symptoms significantly predicted the SID accuracy in clinical participants, supporting its relationship with social motivation processing. CONCLUSION: TRS patients have altered social motivation processing, affecting anticipatory and consummatory pleasure. Social motivation deficit may be an intervention target for negative symptoms and social functioning impairments in TRS patients.