TY - JOUR KW - Diffusion tensor imaging KW - Emotion KW - Frontotemporal dementia KW - Sarcasm KW - Social cognition KW - Voxel based morphometry N2 - Impairments of social cognition are often leading features in frontotemporal lobar degeneration (FTLD) and likely to reflect large-scale brain network disintegration. However, the neuroanatomical basis of impaired social cognition in FTLD and the role of white matter connections have not been defined. Here we assessed social cognition in a cohort of patients representing two core syndromes of FTLD, behavioural variant frontotemporal dementia (bvFTD; n = 29) and semantic variant primary progressive aphasia (svPPA; n = 15), relative to healthy older individuals (n = 37) using two components of the Awareness of Social Inference Test, canonical emotion identification and sarcasm identification. Diffusion tensor imaging (DTI) was used to derive white matter tract correlates of social cognition performance and compared with the distribution of grey matter atrophy on voxel-based morphometry. The bvFTD and svPPA groups showed comparably severe deficits for identification of canonical emotions and sarcasm, and these deficits were correlated with distributed and overlapping white matter tract alterations particularly affecting frontotemporal connections in the right cerebral hemisphere. The most robust DTI associations were identified in white matter tracts linking cognitive and evaluative processing with emotional responses: anterior thalamic radiation, fornix (emotion identification) and uncinate fasciculus (sarcasm identification). DTI associations of impaired social cognition were more consistent than corresponding grey matter associations. These findings delineate a brain network substrate for the social impairment that characterises FTLD syndromes. The findings further suggest that DTI can generate sensitive and functionally relevant indexes of white matter damage in FTLD, with potential to transcend conventional syndrome boundaries. SN - 2213-1582 A1 - Downey, LE A1 - Mahoney, CJ A1 - Buckley, AH A1 - Golden, HL A1 - Henley, SM A1 - Schmitz, N A1 - Schott, JM A1 - Simpson, IJ A1 - Ourselin, S A1 - Fox, NC A1 - Crutch, SJ A1 - Warren, JD EP - 651 SP - 640 AV - public UR - http://dx.doi.org/10.1016/j.nicl.2015.06.005 Y1 - 2015/06/23/ ID - discovery1473083 N1 - © 2015 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). TI - White matter tract signatures of impaired social cognition in frontotemporal lobar degeneration VL - 8 JF - Neuroimage Clinical ER -