Positivity Bias Deficits in Emotional Experience: An EMA Study of Anhedonia in Schizophrenia

People with schizophrenia report anhedonia during structured clinical interviews and on self-report measures, yet when exposed to pleasurable stimuli in experimental paradigms, they report positive hedonic experiences to the same extent as healthy controls. This apparent discordance may be due to abnormalities in how people with schizophrenia anticipate and recall emotional experiences. Healthy people tend to overestimate the magnitude of predicted and recalled emotional events, and we hypothesized that people with schizophrenia would engage in these cognitive biases to a lesser degree. Specifically, we used ecological momentary assessment (EMA) to test the hypothesis that people with schizophrenia would exhibit less of a positivity bias deficit when asked to predict and recall emotional experiences in their daily lives across varying timeframes. Consistent with our hypothesis, people with schizophrenia showed less of a positivity bias when recalling, but not predicting, pleasure over brief time periods compared to healthy controls. People with schizophrenia exhibited a more positive bias, however, than healthy controls when predicting and recalling positive affect, but not negative affect, at 24-hour intervals. Both people with schizophrenia and controls over-estimated the degree of positive and negative affect they would experience over the course of a week and, consistent with the positivity bias deficit hypothesis, people with schizophrenia overestimated positive affect to a lesser degree. Finally, people with schizophrenia reported more pleasure during work/school relative to inactivity than healthy controls and experienced greater increases in pleasure as a function of feelings of closeness to their social interaction partners. Results support the theory that people with schizophrenia exhibit altered patterns of bias with regard to retrospection and prospection of emotional events compared to healthy people.