Cognition and anatomy in three variants of primary progressive aphasia, Ann Neurol 55(3

We performed a comprehensive cognitive, neuroimaging, and genetic study of 31 patients with primary progressive aphasia (PPA), a decline in language functions that remains isolated for at least 2 years. Detailed speech and language evaluation was used to identify three different clinical variants: nonfluent progressive aphasia (NFPA; n 11), semantic dementia (SD; n 10), and a third variant termed logopenic progressive aphasia (LPA; n 10). Voxel-based mor-phometry (VBM) on MRIs showed that, when all 31 PPA patients were analyzed together, the left perisylvian region and the anterior temporal lobes were atrophied. However, when each clinical variant was considered separately, distinctive patterns emerged: (1) NFPA, characterized by apraxia of speech and deficits in processing complex syntax, was associated with left inferior frontal and insular atrophy; (2) SD, characterized by fluent speech and semantic memory deficits, was associated with anterior temporal damage; and (3) LPA, characterized by slow speech and impaired syntactic compre-hension and naming, showed atrophy in the left posterior temporal cortex and inferior parietal lobule. Apolipoprotein E 4 haplotype frequency was 20 % in NFPA, 0 % in SD, and 67 % in LPA. Cognitive, genetic, and anatomical features indicate that different PPA clinical variants may correspond to different underlying pathological processes. Ann Neurol 2004;55:335–346 Isolated speech and language difficulties are often the first symptoms of focal forms of neurodegenerative dis-eases, particularly frontotemporal lobar degeneration (FTLD) and corticobasal degeneration (CBD).1,2 Alz-heimer’s disease (AD) patients also have been shown to present with atypical focal cognitive manifestations, in-cluding fluent and nonfluent progressive aphasia.3–7 When speech and language deficits remain the only complaint for at least 2 years, the term primary progres-sive aphasia (PPA) has been applied.8 Pathologically, the most frequent finding in PPA is an FTLD-type of damage such as dementia lacking dis-tinctive pathology (DLDH)9–11 or Pick’s disease.12,1