Negative symptoms mediate the relationship between social cognition and functioning in schizophrenia: a pilot study

Abstract

In spite of significant advances in pharmacological and psychological treatments, schizophrenia still ranks among the leading causes of disability worldwide. People suffering from schizophrenia have significant impairment in major areas of everyday life, such as interpersonal relationships, work or school and even self-care. Enhancing the understanding of factors that hinder real-life functioning is therefore crucial for translating delivered care into more positive outcomes. Social cognition, defined as the mental operations that underlie social interactions, including perceiving, interpreting, and generating responses to the intentions, dispositions, and behaviors of others, has been implicated in impaired functioning. It is typically broken down into four domains: emotion processing, social perception, attributional bias and theory of mind. Negative symptoms have also been associated with patients' functional outcome; although generally conceptualized as a unitary construct, the most recent literature suggests that these symptoms are heterogeneous and include at least two factors: amotivation and diminished emotional expression. The aim of this study was to analyze the relationships between negative symptoms, social cognition and real-life functioning in people with schizophrenia. Methods: 12 patients with diagnosis of schizophrenia according to ICD-10 criteria were assessed cross-sectionally regarding relevant dimensions to our study: general psychopathology (Positive and Negative Syndrome Scale), social cognition (Face and Emotion Identification Test, Schema Component Sequencing Test - Revised, Social Perception Scale, Ambiguous Intentions and Hostility Questionnaire, Reading the Mind in The Eyes Test), negative symptoms (Clinical Assessment Interview for Negative Symptoms – CAINS) and general functioning (Personal and Social Performance scale – PSP). Spearman correlations were examined and regression and mediation models (Preacher and Hayes bootstrapping methodology) were performed. Results: In our preliminary results, emotion processing was the only social cognition dimension significantly correlated with functioning (rS = .87) and negative symptoms measured by the CAINS: rS = -.78 with amotivation; -.70 with diminished emotional expression and -.78 with total CAINS score (all Po.01). Both amotivation and diminished emotional expression, as well as negative symptoms as a whole, correlated with functioning (rS4.80, Po.01). Emotion processing was a significant predictor of amotivation, diminished emotional expression and total CAINS score (all Beta4-.65, p o.05). Both emotion processing (Beta = .71, P = 0.3) and amotivation (Beta = -.84, P = 0.001) were significant predictors of functioning. Finally, amotivation was found to be a partial mediator of the relationship between emotion processing and functioning (BCA 95% CI = .196 - 7.559). Discussion: Our results are in partial agreement with previous studies suggesting that emotional processing is the most relevant dimension of social cognition to everyday functioning, despite a possible contribution of theory of mind for such impairment in patients with schizophrenia. Regarding negative symptoms, amotivation seems to be the dimension of most relevance to functioning. Altogether, negative symptoms seem to be driven by social cognition deficits and, at least partially, negative symptoms may play a role in the deleterious impact of impaired social cognition on functional outcome. The complexity of the crosstalk between negative symptoms, social cognition and functioning will be better addressed in ongoing studies, as a greater understanding of underlying mechanisms is critical to development of effective treatments.