title: Primary progressive aphasia: linguistic patterns and clinical variants.
abstract: We investigated whether primary progressive aphasias (PPA) reflect non-random degradation of linguistic dimensions that might be supported by different neural subsystems and to what extent this degradation contributes to the emergence of clinical entities: semantic (S), logopenic (L) and nonfluent (NF) aphasia; apraxia of speech was also considered if associated with language disorders (AOS/aph). Forty-two aphasic patients are reported. Two main definable patterns of linguistic deficits tended to emerge that corresponded with identifiable patterns of brain atrophy, and probably diseases: the S variant, which principally expresses the impact of a "deep" cognitive (semantic) disorder on language, and AOS/aph in which "peripheral" executive components play a significant role. By contrast, NF aphasia emerged as a heterogeneous variant due to disorganization of various dimensions within the linguistic domain, that assumes different patterns depending on the differential distribution of atrophy in the perisylvian regions.
authors: Medicine of the Ageing, Department of Geriatrics, Neuroscience and Orthopedics, Italy. Electronic address: mariacaterina.silveri@rm.unicatt.it.
authors: Maria Caterina
authors: MC
authors: Silveri
authors: Department of Neuroimaging, Catholic University, Roma, Italy.
authors: Emanuele
authors: E
authors: Pravatà
authors: Medicine of the Ageing, Department of Geriatrics, Neuroscience and Orthopedics, Italy.
authors: Anna Clelia
authors: AC
authors: Brita
authors: Medicine of the Ageing, Department of Geriatrics, Neuroscience and Orthopedics, Italy.
authors: Erika
authors: E
authors: Improta
authors: Medicine of the Ageing, Department of Geriatrics, Neuroscience and Orthopedics, Italy.
authors: Nicoletta
authors: N
authors: Ciccarelli
authors: Medicine of the Ageing, Department of Geriatrics, Neuroscience and Orthopedics, Italy.
authors: Paola
authors: P
authors: Rossi
authors: Department of Neuroimaging, Catholic University, Roma, Italy.
authors: Cesare
authors: C
authors: Colosimo
mesh_terms: D000368:Aged; D001039:Aphasia, Broca / Q000145:classification / Q000473:pathology / Q000503:physiopathology; D018888:Aphasia, Primary Progressive / Q000145:classification / Q000473:pathology / Q000503:physiopathology*; D001072:Apraxias / Q000503:physiopathology; D001921:Brain / Q000473:pathology / Q000503:physiopathology; D005260:Female; D006801:Humans; D008037:Linguistics; D008297:Male; D012660:Semantics; D013060:Speech
keywords: Agrammatism; Alzheimer’s disease; Apraxia of speech; Corticobasal degeneration; Phonological deficit; Primary progressive aphasia; Semantic deficit; Semantic dementia