Impact of long-term institutionalization on experiential pleasure and motivation in patients with schizophrenia.

Abstract

Anhedonia and amotivation, the hallmarks of negative symptoms in schizophrenia, are believed to be due to "emotion-behavior decoupling," a failure in translating pleasure experience into appropriate goal-directed behavior. A number of studies have reported that long-term institutionalized schizophrenia patients suffer from more severe negative symptoms than community-dwelling patients, but few studies have investigated pleasure experience and motivational behavior in schizophrenia patients who have experienced long-term institutionalization. In this study, we recruited 26 long-term institutionalized schizophrenia patients, 27 community-dwelling schizophrenia patients, and 27 healthy controls. Participants were administered two specific computer-based tasks to assess anhedonia and amotivation. The Anticipatory and Consummatory Pleasure (ACP) Task was used to measure emotion-behavior decoupling and the Effort-Expenditure for Rewards Task (EEfRT) was used to measure amotivation related to rewards. Findings from the ACP Task showed that compared with healthy controls, the coupling between emotion experience and motivated behavior was significantly weaker in both clinical groups, suggesting that emotion-behavior decoupling could be a stable trait in schizophrenia patients. In the EEfRT, compared with both community-dwelling patients and healthy controls, institutionalized patients with schizophrenia failed to expend more effort to gain potential rewards even when reward probability increased. These findings further reveal the underlying mechanism of anhedonia and amotivation and their potential relationships with long-term institutionalization in patients with schizophrenia.