Neuropsychological Correlates of Theory of Mind Deficits in Patients With Multiple Sclerosis
Background: Theory of mind (ToM) is the ability to understand and interpret another person’s beliefs, intentions (cognitive ToM) and emotions (affective ToM). Objective: To explore affective and cognitive ToM and their neuropsychological correlates in patients affected by multiple sclerosis (MS). Material and Method: Forty MS patients and 40 matched control individuals underwent tasks assessing cognitive (the ToM Pictures Sequencing Task and the Advanced Test of ToM) and affective ToM (the Reading the Mind in the Eyes Task and the Emotion Attribution Task), in both verbal and nonverbal modality, a comprehensive neuropsychological battery, and questionnaires for behavioral disorders. Results: MS patients performed significantly worse than controls on tasks assessing cognitive and affective ToM, in verbal and nonverbal modality. Moreover, MS patients achieved significantly lower scores on tests assessing visuospatial learning and speed of spatial information processing, and significantly higher scores on scales for alexithymia and depression with respect to controls. After covarying for cognitive and behavioral variables different in the 2 groups, the differences between patients and controls on ToM tasks remained significant. ToM abilities were significantly related to executive functions, but not to depressive, anxious and apathetic symptoms. Higher alexithymia scores were associated with poor recognition of others’ mental states. Conclusion: The findings demonstrated that both affective and cognitive aspects of ToM are impaired in nondemented and mildly to moderately disabled MS and suggest that impaired social cognition can occur independently from behavioral disorders.