Emotion recognition in multiple sclerosis: The influence of processing speed and cognitive reserve

Social cognitive impairment significantly impacts the quality of life in multiple sclerosis (MS). This study investigated the structural, clinical and functional predictors of emotion recognition in 48 MS patients (26 Relapsing-Remitting, 22 Progressive) and 40 matched healthy controls (HCs). All participants were assessed for emotion recognition (Reading the Mind in the Eyes Test [RMET]). The MS cohort was additionally assessed for information processing speed (IPS) (Symbol Digit Modalities Test [SDMT]) and cognitive reserve (CR) (Cognitive Reserve Index questionnaire [CRIq]). Confounding clinical variables were quantified, including physical disability (Expanded Disability Status Scale [EDSS]), fatigue (Modified Fatigue Impact Scale [MFIS]) and affective symptoms (Depression Anxiety and Stress Scale [DASS-21]). Regional cortical volumes were extracted utilizing 3T MRI automated parcellation. Patients with Progressive MS exhibited profound emotion recognition deficits compared to HCs (p = 0.006). Multivariate regression identified IPS (β = 0.352) and CR (β = 0.289) as the only significant independent predictors of RMET accuracy. These functional variables statistically eclipsed the influence of focal anterior insular atrophy, perceived fatigue and mood symptoms. Emotion recognition impairment in MS is primarily driven by two independent, additive predictors: IPS and CR. Together, these functional determinants outweigh the influence of focal macroscopic cortical damage, fatigue and mood symptoms.