White and gray matter correlates of executive functions and social cognition impairment in MS (P6.137)

Introduction: Executive Functions (EF) and social cognition (SC) have been shown to be impaired in MS. Previous morphometry studies evidenced atrophy of cortical sites in MS including the insular cortex (IC) and primary somatosensorial cortex (S1) which are crucial hubs of the salience network for bodily sensation and social cognition domains.Objective:Here we evaluate the atrophy of specific nodes of the salience network in MS and relate them to EF and SC deficits.Methods:20 RRME patients (mean age=40.3; mean EDSS=2) were assessed with neuropsychology tests of EF (Phonological Fluency, Hayling test, INECO-Frontal-screening [IFS] and PASAT) and SC (reading the mind in the eyes, Faux Pas test) and voxel-based morphometry of white matter (WM) and gray matter (GM) of structural magnetic resonance imaging.Results:GM and WM atrophy in patients with MS involved a pattern of frontal, parietal and occipital atrophy. Phonological fluency correlated with atrophy of bilateral S1-IC (r=0.59;p=.01), whereas processing speed correlated with atrophy of bilateral insula (r=0.56;p=.01), inhibitory control correlated with atrophy of left S1-IC (r=0.64;pu003c.01); IFS correlated with bilateral insula and left S1 (r=0.48;p=.03). Regarding WM tracts, phonological fluency correlated with atrophy of left superior corona radiata (r=0.48;p=.03). Finally, SC performance correlated with bilateral S1-insula (r=0.53;p=.01), as well as with right superior longitudinal fasciculus (r=0.47;p=.03).Conclusions:The WM and GM atrophy showed a pattern of frontal areas. EF and SC tasks correlated with salience network nodes atrophy confirming that atrophy of sites such as IC, S1 and the underlying WM tracts connecting them correlate with the patient´s behavior in those domains. This is in line with previous engagement of IC and S1 in the salience network related to the integration of higher cognitive functions (i.e. executive functions) and affective-driven behavior (i.e. social cognition). Disclosure: Dr. Couto has nothing to disclose. Dr. Bruno has nothing to disclose. Dr. Sedeno has nothing to disclose. Dr. Sinay has nothing to disclose. Dr. Pagani Cassara has nothing to disclose. Dr. Esteves has nothing to disclose. Dr. Manes has nothing to disclose. Dr. Roca has nothing to disclose. Dr. Ibanez has nothing to disclose.