LAUSR

Abstract Background A pragmatic disruption is observed in several clinical conditions and especially in schizophrenia. It is estimated that over 75% of patients affected by schizophrenia present a pervasive and wide impairment of pragmatic abilities, encompassing both comprehension and production abilities, thus confirming the hypothesis of a wide Pragmatic Language Disorder in schizophrenia. More specifically, the comprehension of figurative languages, such as metaphors, idioms, and irony, is the most compromised domain in schizophrenia. Poor pragmatics has a relevant impact on daily functioning, by contributing to social isolation and lower quality of life. Only few pragmatic treatments have been developed and tested in schizophrenia, focusing only on specific pragmatic features and without using a Randomized Controlled Trial (RCT) design. This study aimed at investigating the efficacy of PragmaCom Training (PT), a novel 12-weeks intervention specifically developed to enhance pragmatics in schizophrenia. Methods 30 patients with schizophrenia, according to DSM 5, were randomly assigned to PT to an active control group (ACG). All patients were assessed for global pragmatics with the Assessment of Pragmatic Abilities and Cognitive Substrates test, APACS), metaphor comprehension (Physical and Mental Metaphors task, PMM), executive functions (Brief Assessment of Cognition in Schizophrenia, Tower of London score, BACS), abstract thinking (Positive and Negative Syndrome Scale for Schizophrenia, N5 score, PANSS), and daily functioning (Quality of Life Scale, QLS). To quantify the magnitude of changes after the PT, effect sizes were estimated using Cohen’s d (Cohen, 1988) for APACS, PMM, PANSS N5 Score, and QLS only in PT Group. The effect of PT in enhancing pragmatic abilities, the abstract thinking and daily functioning was tested between groups by means of several ANCOVA, entering post-training measures as dependent variables, measures at the baseline and executive functions as covariates, and treatment (PT vs ACG) as grouping variables. Results Patients treated with PT showed small to medium-large effect-sizes in global pragmatics (0.25), metaphors comprehension (0.72), functioning (0.23), and abstract thinking (-0.18). ANCOVAs revealed a significant effect of PT in enhancing global pragmatic abilities (F=5.4, p=.03), metaphor comprehension (F=8.94, p=.007) and abstract thinking (F=8.1, p=.01). No significant effect was found for functioning. Discussion This is the first study using a RCT design to test the efficacy of a pragmatic training. PT is a novel training specifically developed to target the pragmatic impairments that characterize schizophrenia. This study confirms the efficacy of PT in improving multiple domains, encompassing global pragmatics, the comprehension of figurative language, and abstract thinking in schizophrenia. Impact on functioning is also expected. However, in line with literature, it is likely to occur at later time points, since it requires the chance to apply the enhanced abilities in ecological contexts.