Are idiom comprehension difficulties in patients with schizophrenia due to working memory and executive deficits?

Background and Objectives: We investigated idiom comprehension in patients with schizophrenia, and the involvement of working memory and executive functions in this comprehension. Methods: Nineteen patients with schizophrenia aged 22-46 years (mean = 34.73 years) took part in this study, and were matched for age and education level with a control group. Our assessment consisted of (1) an experimental task assessing idiom comprehension through short stories, (2) three tasks assessing verbal, visuospatial and multimodal spans, and (3) four tasks assessing executive functions (Hayling test, Stroop test, Wisconsin Card Sorting Test and Trail Making Test). Results and Conclusion: Results highlighted several deficits in the comprehension of idioms in patients with schizophrenia. An executive deficit is not sufficient to explain these difficulties. Nevertheless, the conceptual disorganization observed in the patients conduce them to not focus their attention on the relevant elements avoiding the comprehension of idioms.