A new perspective on anhedonia in schizophrenia

Abstract

Objective: Previous research provides evidence for discrepancies in various types of emotional self-report in individuals with schizophrenia; patients and healthy subjects report similar levels of positive emotion when reporting current feelings, yet patients report lower levels of positive emotion when reporting on noncurrent feelings. Such apparent discrepancies, which have come to be termed the "emotion paradox" in schizophrenia, have complicated our understanding of what anhedonia actually reflects in this patient population. The authors sought to resolve this paradox.

Method: The authors reviewed the empirical literature on anhedonia and emotional experience in schizophrenia through the lens of the accessibility model of emotional self-report, a well-validated model of emotional self-report developed in the affective science literature that clarifies the sources of emotion knowledge that individuals access when providing different types of self-report. The authors used this model to propose a resolution to the "emotion paradox" and to provide a new psychological conceptualization of anhedonia.

Results: Data are presented in support of this new perspective on anhedonia and to demonstrate how cognitive impairments may influence reports of noncurrent feelings in schizophrenia.

Conclusions: The authors conclude that anhedonia should no longer be considered an experiential deficit or a diminished "capacity" for pleasure in patients with schizophrenia. Rather, anhedonia reflects a set of beliefs related to low pleasure that surface when patients are asked to report their noncurrent feelings. Encoding and retrieval processes may serve to maintain these beliefs despite contrary real-world pleasurable experiences. Implications for assessment and treatment are discussed in relation to this new conceptualization of anhedonia.

Figure 1

Diagram of the four sources of information accessible when providing emotional self-report according to Robinson & Clore’s Model. The Accessibility Model proposes that individuals access 4 sources of information when providing emotional self-report. Experiential and episodic information rely on episodic emotion knowledge, whereas situation-specific and identity-related beliefs rely on semantic emotion knowledge. Individuals prioritize the most specific source of knowledge that is available to them and relevant to the response format being used. The middle column illustrates the hierarchy of information prioritization. The right column depicts the most common types of emotional self-report that are likely to be based upon the different sources of information.

Figure 2

Mean HVLT/BVMT MATRICS T-Scores in Patients with High and Low SANS Anhedonia Ratings. Behavioral and characterizing data originally published in Strauss et al. (29). Participants included 86 individuals with DSM-IV diagnoses of schizophrenia or schizoaffective disorder and 59 healthy controls recruited from the community. Groups did not differ on age, parental education, gender, or race. Individuals with schizophrenia were divided into high (Hi-ANH) and low (LOW-ANH) anhedonia groups according to average scores across all anhedonia items on the Scale for the Assessment of Negative Symptoms. HI-ANH patients had mean ratings of 2 or greater (mild severity or higher). Low-ANH patients had mean ratings less than 2 (questionable or absent). Groups were compared on the mean MATRICS battery t-score of BVMT/HVLT items (mean = 50; standard deviation = 10). HI-ANH and LOW-ANH significantly differed in mean memory performance, F (1, 85) = 6.02, p = 0.01, such that HI-ANH had poorer memory performance than LOW-ANH patients.

Figure 3

Diagram of the new psychological perspective on anhedonia We propose that anhedonia has three components: 1) low pleasure beliefs and the lack of prospective/retrospective overestimation of positive emotion, 2) reduced pleasure-seeking behavior, and 3) elevated negative emotions. These three components may interact with one another. Low pleasure beliefs consist of situation-specific and/or identity-related beliefs. Encoding and retrieval processes maintain low pleasure beliefs.