title: Impairment of social cognition in multiple sclerosis: Amygdala atrophy is the main predictor.
abstract: BACKGROUND
  Patients with multiple sclerosis (MS) frequently reveal social behavior disturbance. Nevertheless, little is known regarding the impact of MS on social cognition, particularly theory of mind (ToM), and its neural basis.
  
  
  OBJECTIVE
  To explore how ToM is affected in MS and its neural correlates.
  
  
  METHODS
  Enrolled 60 consecutive MS patients and 60 healthy controls (HC) matched on age, sex, and education. Participants underwent ToM testing (Eyes Test, Videos Test) and 3 T brain magnetic resonance imaging (MRI). Using Freesurfer software, cortical and subcortical gray matter (GM) volumes were calculated.
  
  
  RESULTS
  MS patients performed worse on Eyes Test (58.7% ± 13.8% vs 81.9% ± 10.4%, p < 0.001) and Videos Test (75.3% ± 9.3% vs 88.1% ± 7.1%, p < 0.001). Eyes Test performance in MS was positively correlated with the volume of subcortical structures (amygdala, putamen) and cortical regions (entorhinal cortex, fusiform gyrus, superior temporal gyrus, superior parietal gyrus, supramarginal gyrus, medial orbitofrontal cortex, anterior and posterior cingulate gyrus). In regression analysis, amygdala volume was the single predictor of performance ( R2change = 0.064, p = 0.031), and a mediation analysis indicated that it contributes for the differences observed between MS and HC.
  
  
  CONCLUSIONS
  Patients with MS have impairment on social cognition. Amygdala atrophy was the main predictor probably due to its central position within the "social brain" network.
authors.affiliation: Department of Neurology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal/Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
authors.forename: Sonia
authors.initials: S
authors.lastname: Batista
authors.affiliation: Visual Neuroscience Laboratory, Institute for Biomedical Imaging and Life Sciences (IBILI), Faculty of Medicine, University of Coimbra, Coimbra, Portugal/Centre for Neuroscience and Cell Biology (CNC), Institute for Biomedical Imaging and Life Sciences (IBILI), University of Coimbra, Coimbra, Portugal/Institute for Nuclear Sciences Applied to Health (ICNAS), University of Coimbra, Coimbra, Portugal.
authors.forename: Otília C
authors.initials: OC
authors.lastname: d'Almeida
authors.affiliation: Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
authors.forename: Ana
authors.initials: A
authors.lastname: Afonso
authors.affiliation: Centre for Neuroscience and Cell Biology (CNC), Institute for Biomedical Imaging and Life Sciences (IBILI), University of Coimbra, Coimbra, Portugal/Centro de Investigação do Núcleo de Estudos e Intervenção Cognitivo Comportamental (CINEICC), University of Coimbra, Coimbra, Portugal/Psychological Assessment Lab, Faculty of Psychology and Educational Sciences, University of Coimbra, Coimbra, Portugal.
authors.forename: Sandra
authors.initials: S
authors.lastname: Freitas
authors.affiliation: Department of Neurology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.
authors.forename: Carmo
authors.initials: C
authors.lastname: Macário
authors.affiliation: Department of Neurology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal/Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
authors.forename: Lívia
authors.initials: L
authors.lastname: Sousa
authors.affiliation: Visual Neuroscience Laboratory, Institute for Biomedical Imaging and Life Sciences (IBILI), Faculty of Medicine, University of Coimbra, Coimbra, Portugal/Centre for Neuroscience and Cell Biology (CNC), Institute for Biomedical Imaging and Life Sciences (IBILI), University of Coimbra, Coimbra, Portugal/Institute for Nuclear Sciences Applied to Health (ICNAS), University of Coimbra, Coimbra, Portugal.
authors.forename: Miguel
authors.initials: M
authors.lastname: Castelo-Branco
authors.affiliation: Department of Neurology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal/Faculty of Medicine, University of Coimbra, Coimbra, Portugal; Centre for Neuroscience and Cell Biology (CNC), Institute for Biomedical Imaging and Life Sciences (IBILI), University of Coimbra, Coimbra, Portugal.
authors.forename: Isabel
authors.initials: I
authors.lastname: Santana
authors.affiliation: Department of Neurology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal/Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
authors.forename: Luís
authors.initials: L
authors.lastname: Cunha
mesh_terms: D000328:Adult; D000679:Amygdala / Q000473:pathology*; D001284:Atrophy; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D001523:Mental Disorders / Q000209:etiology / Q000473:pathology; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000473:pathology* / Q000523:psychology*; D009483:Neuropsychological Tests; D012919:Social Behavior; D056345:Theory of Mind
keywords: Multiple sclerosis; amygdala; social brain; social cognition; theory of mind