Does surface dyslexia/dysgraphia relate to semantic deficits in the semantic variant of primary progressive aphasia?

The semantic variant of primary progressive aphasia (sv-PPA) is a degenerative condition which causes surface dyslexia/dysgraphia, resulting in reading/writing errors of irregular words with non-transparent grapheme-to-phoneme correspondences (e.g., 'plaid') as opposed to regular words (e.

Parietal Involvement in the Semantic Variant of Primary Progressive Aphasia with Alzheimer's Disease Cerebrospinal Fluid Profile.

Semantic variant of primary progressive aphasia (svPPA) is typically associated with non-Alzheimer's disease (AD) pathology. However, some anatomopathological studies have found AD lesions in those patients. We compared brain perfusion SPECT of 18 svPPA patients with cerebrospinal fluid (CSF) biomarkers indicative of non-AD pathology (svPPA-nonAD) and three svPPA patients with CSF biomarkers indicative of underlying AD (svPPA-AD).

The Brain Network of Naming: A Lesson from Primary Progressive Aphasia.

Objective: Word finding depends on the processing of semantic and lexical information, and it involves an intermediate level for mapping semantic-to-lexical information which also subserves lexical-to-semantic mapping during word comprehension. However, the brain regions implementing these components are still controversial and have not been clarified via a comprehensive lesion model encompassing the whole range of language-related cortices. Primary progressive aphasia (PPA), for which anomia is thought to be the most common sign, provides such a model, but the exploration of cortical areas impacting naming in its three main variants and the underlying processing mechanisms is still lacking.

Deciphering logopenic primary progressive aphasia: a clinical, imaging and biomarker investigation.

Within primary progressive aphasia the logopenic variant remains less understood than the two other main variants, namely semantic and non-fluent progressive aphasia. This may be because of the relatively small number of explored patients and because of the lack of investigations with a comprehensive three-level characterization of cognitive, brain localization and biological aspects. The aim of the present study was to decipher the logopenic variant through a multimodal approach with a large cohort of 19 patients (age 66.