Communication in Multiple Sclerosis: Pragmatic Deficit and its Relation with Cognition and Social Cognition

Objective: Cognitive functions have been largely investigated in multiple sclerosis. Less attention has been paid to social communication abilities, despite their presumptive affect on quality of life. We run the first comprehensive assessment of pragmatic skills in multiple sclerosis, evaluating also the relationship between pragmatics and other cognitive domains. Methods: Forty-two multiple sclerosis patients and 42 controls were tested for pragmatic abilities, neuro-cognition, social cognition, depression, and fatigue. Results: Patients performed poorly in most pragmatic tasks compared to controls. Globally, 55% of patients performed below the 5th percentile in the total pragmatic score. Notably, pragmatic skills did not differ between cognitively impaired and unimpaired patients. However, an association was found between pragmatics and verbal fluency, as measured in the Word List Generation. Finally, we observed an association of pragmatic abilities with social cognition, and a trend with psychosocial functioning. Conclusion: Overall, the study shows a diffuse pragmatic impairment in multiple sclerosis, not associated with the patient's global neuropsychological profile. By contrast, our findings suggest a close relation between pragmatics and specific cognitive aspects such as executive functions, and between pragmatics and social cognition. This study underlines the need of looking beyond classical cognitive performance, to consider underestimated communicative disturbances of high clinical relevance.