RT Journal Article T1 Abnormal functional connectivity in radiologically isolated syndrome: A resting-state fMRI study A1 Benito León, Julián A1 Pino, Ana Belén del A1 Aladro, Yolanda A1 Cuevas, Constanza A1 Domingo-Santos, Ángela A1 Galán Sánchez-Seco, Victoria A1 Labiano-Fontcuberta, Andrés A1 Gómez-López, Ana A1 Salgado-Cámara, Paula A1 Costa-Frossard, Lucienne A1 Monreal, Enrique A1 Sainz de la Maza, Susana A1 Matias-Guiu Antem, Jordi A1 Matías-Guiu Guía, Jorge A1 Delgado Álvarez, Alfonso A1 Montero-Escribano, Paloma A1 Martínez-Ginés, María Luisa A1 Higueras Hernández, Yolanda A1 Ayuso-Peralta, Lucía A1 Malpica, Norberto A1 Melero Carrasco, Helena AB Background: Radiologically isolated syndrome (RIS) patients might have psychiatric and cognitive deficits, which suggests an involvement of major resting-state functional networks. Notwithstanding, very little is known about the neural networks involved in RIS. Objective: To examine functional connectivity differences between RIS and healthy controls using resting-state functional magnetic resonance imaging (fMRI). Methods: Resting-state fMRI data in 25 RIS patients and 28 healthy controls were analyzed using an independent component analysis; in addition, seed-based correlation analysis was used to obtain more information about specific differences in the functional connectivity of resting-state networks. Participants also underwent neuropsychological testing. Results: RIS patients did not differ from the healthy controls regarding age, sex, and years of education. However, in memory (verbal and visuospatial) and executive functions, RIS patients’ cognitive performance was significantly worse than the healthy controls. In addition, fluid intelligence was also affected. Twelve out of 25 (48%) RIS patients failed at least one cognitive test, and six (24.0%) had cognitive impairment. Compared to healthy controls, RIS patients showed higher functional connectivity between the default mode network and the right middle and superior frontal gyri and between the central executive network and the right thalamus ( pFDR < 0.05; corrected). In addition, the seed-based correlation analysis revealed that RIS patients presented higher functional connectivity between the posterior cingulate cortex, an important hub in neural networks, and the right precuneus. Conclusion: RIS patients had abnormal brain connectivity in major resting-state neural networks and worse performance in neurocognitive tests. This entity should be considered not an “incidental finding” but an exclusively non-motor (neurocognitive) variant of multiple sclerosis. PB SAGE SN 1352-4585 SN 1477-0970 YR 2023 FD 2023-09 LK https://hdl.handle.net/20.500.14352/103893 UL https://hdl.handle.net/20.500.14352/103893 LA eng NO Benito-León J, del Pino AB, Aladro Y, et al. Abnormal functional connectivity in radiologically isolated syndrome: A resting-state fMRI study. Multiple Sclerosis Journal. 2023;29(11-12):1393-1405. doi:10.1177/13524585231195851 NO National Institutes of Health (EEUU) NO European Commission NO Ministerio de Economía y Competitividad (España) NO Ministerio de Ciencia e Innovación (España) DS Docta Complutense RD 27 dic 2025