Nonfluent Aphasia (nonfluent + aphasia)

Distribution by Scientific Domains

Selected Abstracts

Language Processing in Frontotemporal Dementia: A Brief Review

Jonathan E. Peelle
Frontotemporal dementia (FTD) is a neurodegenerative condition that presents with a number of distinct behavioral phenotypes. Here we review language-processing deficits in three subgroups of FTD patients: progressive nonfluent aphasia (PNFA), semantic dementia (SD), and nonaphasic FTD patients with a disorder of social and executive functioning (SOC/EXEC). These three clinical subgroups have contrasting patterns of regional cortical atrophy that can be linked to their language impairments. PNFA patients' disease includes left ventral inferior frontal cortex, resulting in impaired grammatical processing. SD patients demonstrate a profound impairment for semantic knowledge related to atrophy of the left temporal lobe. SOC/EXEC patients' frontal atrophy tends to be more right lateralized and is associated with declines in executive functioning. SOC/EXEC patients' limited executive resources impact language processing in a variety of ways, including slowed grammatical processing and impaired narrative discourse. FTD patients therefore provide converging evidence regarding dissociable components of language processing and their neuroanatomical bases. [source]

Corticobasal degeneration as a cognitive disorder

Naida L. Graham PhD
Abstract The presence of cognitive impairment in corticobasal degeneration (CBD) is now widely recognised. Our review of the literature reveals that, although the pattern and severity of neuropsychological impairments can be highly variable across patients, several general trends can be identified. The most characteristic impairments are limb apraxia (usually ideomotor), constructional and visuospatial difficulties, acalculia, frontal dysfunction, and nonfluent aphasia. The limb apraxia is associated with deficits in drawing, copying, and handwriting, but there is emerging evidence that the problems with handwriting are not due exclusively to the apraxia. The findings with respect to episodic memory are more variable, but when there is impairment in this area, it tends to be milder than that seen in Alzheimer's disease. Semantic memory functioning appears relatively preserved but has been poorly studied. Problems with speech are common, and may be due to dysarthria or buccofacial apraxia. Aphasia, although initially considered rare, is in fact a common accompaniment of CBD, may be the presenting feature, and is typically nonfluent in type. More systematic investigation of the clinical and neuropathological overlap between progressive nonfluent aphasia (generally considered to be a form of frontotemporal dementia) and CBD is needed. 2003 Movement Disorder Society [source]

A, amyloid and glucose metabolism in three variants of primary progressive aphasia

Gil D. Rabinovici MD
Objective Alzheimer's disease (AD) is found at autopsy in up to one third of patients with primary progressive aphasia (PPA), but clinical features that predict AD pathology in PPA are not well defined. We studied the relationships between language presentation, A, amyloidosis, and glucose metabolism in three PPA variants using [11C]-Pittsburgh compound B ([11C]PIB) and [18F]-labeled fluorodeoxyglucose positron emission tomography ([18F]FDG-PET). Methods Patients meeting PPA criteria (N = 15) were classified as logopenic aphasia (LPA), progressive nonfluent aphasia (PNFA), or semantic dementia (SD) based on language testing. [11C]PIB distribution volume ratios were calculated using Logan graphical analysis (cerebellar reference). [18F]FDG images were normalized to pons. Partial volume correction was applied. Results Elevated cortical PIB (by visual inspection) was more common in LPA (4/4 patients) than in PNFA (1/6) and SD (1/5) (p < 0.02). In PIB-positive PPA, PIB uptake was diffuse and indistinguishable from the pattern in matched AD patients (n = 10). FDG patterns were focal and varied by PPA subtype, with left temporoparietal hypometabolism in LPA, left frontal hypometabolism in PNFA, and left anterior temporal hypometabolism in SD. FDG uptake was significant asymmetric (favoring left hypometabolism) in PPA (p < 0.005) but not in AD. Interpretation LPA is associated with A, amyloidosis, suggesting that subclassification of PPA based on language features can help predict the likelihood of AD pathology. Language phenotype in PPA is closely related to metabolic changes that are focal and anatomically distinct between subtypes, but not to amyloid deposition patterns that are diffuse and similar to AD. Ann Neurol 2008 [source]