Neuropsychological, Behavioral, and Anatomical Evolution in Right Temporal Variant Frontotemporal Dementia: A Longitudinal Single Case Analysis

We examine longitudinal clinical and anatomical data for a patient with the right temporal variant of frontotemporal dementia. The patient received comprehensive clinical evaluations and structural MRI scans over three years. She presented with early behavioral deficits and ultimately developed semantic impairments consistent with the semantic variant of primary progressive aphasia. Imaging revealed early atrophy of the right temporal lobe, with later involvement of the left, and pathology confirmed bilateral temporal involvement. Findings support the view that right and left temporal variants reflect early asymmetry of atrophy that may become more bilateral over time, resulting in a mixed clinical picture

Anatomical correlates of early mutism in progressive nonfluent aphasia

Patients with progressive nonfluent aphasia (PNFA) can become mute early in the course of the disease. Voxel-based morphometry showed that PNFA is associated with left anterior insula and inferior frontal atrophy. In PNFA with early mutism, volume loss was more prominent in the pars opercularis and extended into the left basal ganglia. Damage to the network of brain regions involved in both coordination and execution of speech causes mutism in PNFA

An Overview on Primary Progressive Aphasia and Its Variants

We present a review of the literature on Primary Progressive Aphasia (PPA) together with the analysis of neuropschychological and neuroradiologic profiles of 42 PPA patients. Mesulam originally defined PPA as a progressive degenerative disorder characterized by isolated language impairment for at least two years. The most common variants of PPA are: (1) Progressive nonfluent aphasia (PNFA), (2) semantic dementia (SD), (3) logopenic progressive aphasia (LPA). PNFA is characterized by labored speech, agrammatism in production, and/or comprehension. In some cases the syndrome begins with isolated deficits in speech. SD patients typically present with loss of word and object meaning and surface dyslexia. LPA patients have word-finding difficulties, syntactically simple but accurate language output and impaired sentence comprehension. The neuropsychological data demonstrated that SD patients show the most characteristic pattern of impairment, while PNFA and LPA overlap within many cognitive domains. The neuroimaging analysis showed left perisylvian region involvement. A comprehensive cognitive, neuroimaging and pathological approach is necessary to identify the clinical and pathogenetic features of different PPA variants

An overview on Primary Progressive Aphasia and its variants.

We present a review of the literature on Primary Progressive Aphasia (PPA) together with the analysis of neuropschychological and neuroradiologic profiles of 42 PPA patients. Mesulam originally defined PPA as a progressive degenerative disorder characterized by isolated language impairment for at least two years. The most common variants of PPA are: 1) Progressive nonfluent aphasia (PNFA), 2) semantic dementia (SD), 3) logopenic progressive aphasia (LPA). PNFA is characterized by labored speech, agrammatism in production, and/or comprehension. In some cases the syndrome begins with isolated deficits in speech. SD patients typically present with loss of word and object meaning and surface dyslexia. LPA patients have word-finding difficulties, syntactically simple but accurate language output and impaired sentence comprehension. The neuropsychological data demonstrated that SD patients show the most characteristic pattern of impairment, while PNFA and LPA overlap within many cognitive domains. The neuroimaging analysis showed left perisylvian region involvement. A comprehensive cognitive, neuroimaging and pathological approach is necessary to identify the clinical and pathogenetic features of different PPA variants

An Overview on Primary Progressive Aphasia and Its Variants

We present a review of the literature on Primary Progressive Aphasia (PPA) together with the analysis of neuropschychological and neuroradiologic profiles of 42 PPA patients. Mesulam originally defined PPA as a progressive degenerative disorder characterized by isolated language impairment for at least two years. The most common variants of PPA are: (1) Progressive nonfluent aphasia (PNFA), (2) semantic dementia (SD), (3) logopenic progressive aphasia (LPA). PNFA is characterized by labored speech, agrammatism in production, and/or comprehension. In some cases the syndrome begins with isolated deficits in speech. SD patients typically present with loss of word and object meaning and surface dyslexia. LPA patients have word-finding difficulties, syntactically simple but accurate language output and impaired sentence comprehension. The neuropsychological data demonstrated that SD patients show the most characteristic pattern of impairment, while PNFA and LPA overlap within many cognitive domains. The neuroimaging analysis showed left perisylvian region involvement. A comprehensive cognitive, neuroimaging and pathological approach is necessary to identify the clinical and pathogenetic features of different PPA variants

Neuropsychological, behavioral, and anatomical evolution in right temporal variant frontotemporal dementia: A longitudinal and post-mortem single case analysis

We describe a patient with semantic variant of frontotemporal dementia who received longitudinal clinical evaluations and structural MRI scans and subsequently came to autopsy. She presented with early behavior changes and semantic loss for foods and people and ultimately developed a pervasive semantic impairment affecting social-emotional as well as linguistic domains. Imaging revealed predominant atrophy of the right temporal lobe, with later involvement of the left, and pathology confirmed bilateral temporal involvement. Findings support the view that left and right anterior temporal lobes serve as semantic hubs that may be affected differentially in semantic variant by early, relatively unilateral damage

Inflectional morphology in primary progressive aphasia: An elicited production study

Inflectional morphology lies at the intersection of phonology, syntax and the lexicon, three language domains that are differentially impacted in the three main variants of primary progressive aphasia (PPA). To characterize spared and impaired aspects of inflectional morphology in PPA, we elicited inflectional morphemes in 48 individuals with PPA and 13 healthy age-matched controls. We varied the factors of regularity, frequency, word class, and lexicality, and used voxel-based morphometry to identify brain regions where atrophy was predictive of deficits on particular conditions. All three PPA variants showed deficits in inflectional morphology, with the specific nature of the deficits dependent on the anatomical and linguistic features of each variant. Deficits in inflecting low-frequency irregular words were associated with semantic PPA, with lexical/semantic deficits, and with left temporal atrophy. Deficits in inflecting pseudowords were associated with non-fluent/agrammatic and logopenic variants, with phonological deficits, and with left frontal and parietal atrophy

In vivo signatures of nonfluent/agrammatic primary progressive aphasia caused by FTLD pathology

ObjectiveTo identify early cognitive and neuroimaging features of sporadic nonfluent/agrammatic variant of primary progressive aphasia (nfvPPA) caused by frontotemporal lobar degeneration (FTLD) subtypes.MethodsWe prospectively collected clinical, neuroimaging, and neuropathologic data in 11 patients with sporadic nfvPPA with FTLD-tau (nfvPPA-tau, n = 9) or FTLD-transactive response DNA binding protein pathology of 43 kD type A (nfvPPA-TDP, n = 2). We analyzed patterns of cognitive and gray matter (GM) and white matter (WM) atrophy at presentation in the whole group and in each pathologic subtype separately. We also considered longitudinal clinical data.ResultsAt first evaluation, regardless of pathologic FTLD subtype, apraxia of speech (AOS) was the most common cognitive feature and atrophy involved the left posterior frontal lobe. Each pathologic subtype showed few distinctive features. At presentation, patients with nfvPPA-tau presented with mild to moderate AOS, mixed dysarthria with prominent hypokinetic features, clear agrammatism, and atrophy in the GM of the left posterior frontal regions and in left frontal WM. While speech and language deficits were prominent early, within 3 years of symptom onset, all patients with nfvPPA-tau developed significant extrapyramidal motor signs. At presentation, patients with nfvPPA-TDP had severe AOS, dysarthria with spastic features, mild agrammatism, and atrophy in left posterior frontal GM only. Selective mutism occurred early, when general neurologic examination only showed mild decrease in finger dexterity in the right hand.ConclusionsClinical features in sporadic nfvPPA caused by FTLD subtypes relate to neurodegeneration of GM and WM in frontal motor speech and language networks. We propose that early WM atrophy in nfvPPA is suggestive of FTLD-tau pathology while early selective GM loss might be indicative of FTLD-TDP