A cognitive model of diminished expression in schizophrenia: The interface of metacognition, cognitive symptoms and language disturbances

Helena García-Mieres, Nancy B Lundin, Kyle S Minor, Giancarlo Dimaggio, Raffaele Popolo, Simone Cheli, Paul H Lysaker, Helena García-Mieres, Nancy B Lundin, Kyle S Minor, Giancarlo Dimaggio, Raffaele Popolo, Simone Cheli, Paul H Lysaker

Abstract

The resistance of negative symptoms to pharmacologic treatment has spurred interest in understanding the psychological factors that contribute to their formation and persistence. However, little is understood about the psychological processes that reinforce and sustain the negative symptoms domain of diminished expression. Prior research has shown that higher levels of diminished expression relate to deficits in metacognitive capacity. We propose a more complex model in which diminished expression occurs when impairments in metacognitive self-reflectivity, alterations in higher-order language structure, and cognitive symptoms interact and thus interfere with persons' ability to understand and express emotions in ways others can recognize. Individuals with schizophrenia-spectrum disorders (N = 201) provided personal narratives detailing their life story and reflections about their mental illness. Self-reflectivity was measured with the Metacognition Assessment Scale-Abbreviated, and situation models were extracted from participants' personal narratives via Coh-Metrix 3.0, an automated program that calculates language indices. Diminished expression and cognitive symptoms were measured with the Positive and Negative Syndrome Scale. Structural equation models (SEM) examined whether self-reflectivity mediated the impact of cognitive symptoms and situation models on diminished expression. Results of the SEM revealed that self-reflectivity partially mediated the impact of situation models on diminished expression (β = -.073, p = .008, ±95% CI [-0.126, -0.019]). and fully mediated the influence of cognitive symptoms in diminished expression (β = 0.099, p = .001, ±95% CI [0.038, 0.160]). In conclusion, results suggest that self-reflectivity, linguistic cohesion, and cognitive symptoms may be useful targets for intervention in efforts to treat diminished expression in psychosis.

Keywords: Expressive deficit; Metacognition; Negative symptoms; Psychosis; Schizophrenia; Self-reflectivity.

Conflict of interest statement

Declaration of competing interest

The authors have no conflicts of interest to declare.

Published by Elsevier Ltd.

Figures

Fig. 1.
Fig. 1.
Self-reflectrivity partially mediates the impact of situations models on diminished expression.

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