title: Semantic dementia: a specific network-opathy.
abstract: Semantic dementia (SD) is a unique syndrome in the frontotemporal lobar degeneration spectrum. Typically presenting as a progressive, fluent anomic aphasia, SD is the paradigmatic disorder of semantic memory with a characteristic anatomical profile of asymmetric, selective antero-inferior temporal lobe atrophy. Histopathologically, most cases show a specific pattern of abnormal deposition of protein TDP-43. This relatively close clinical, anatomical and pathological correspondence suggests SD as a promising target for future therapeutic trials. Here, we discuss outstanding nosological and neurobiological challenges posed by the syndrome and propose a pathophysiological model of SD based on sequential, regionally determined disintegration of a vulnerable neural network.
authors.affiliation: Dementia Research Centre, Institute of Neurology, University College London, 8-11 Queen Square, London, WC1N 3BG, UK.
authors.forename: Phillip D
authors.initials: PD
authors.lastname: Fletcher
authors.forename: Jason D
authors.initials: JD
authors.lastname: Warren
mesh_terms: D001037:Aphasia / Q000473:pathology / Q000503:physiopathology; D001921:Brain / Q000033:anatomy & histology / Q000473:pathology / Q000503:physiopathology; D002986:Clinical Trials as Topic; D057174:Frontotemporal Lobar Degeneration / Q000473:pathology* / Q000503:physiopathology*; D006801:Humans; D008959:Models, Neurological; D009415:Nerve Net / Q000473:pathology* / Q000503:physiopathology*; D009483:Neuropsychological Tests