Logopenic variant

BACKGROUND: Clinical variants of primary progressive aphasia (PPA) are diagnosed based on characteristic patterns of language deficits, supported by corresponding neural changes on brain imaging. However, there is (i) considerable phenotypic variability within and between each diagnostic category with partially overlapping profiles of language performance between variants and (ii) accompanying non-linguistic cognitive impairments that may be independent of aphasia magnitude and disease severity...

BACKGROUND: Binary reversals (exemplified by 'yes'/'no' confusions) have been described in patients with primary progressive aphasia (PPA) but their diagnostic value and phenotypic correlates have not been defined. METHODS: We conducted a retrospective cohort study analysing demographic, clinical, neuropsychological, linguistic and behavioural data from patients representing all major PPA syndromes (non-fluent/agrammatic variant, nfvPPA; logopenic variant, lvPPA; semantic variant, svPPA) and behavioural variant frontotemporal dementia (bvFTD)...

Posterior cortical atrophy (PCA) is a rare neurodegenerative condition characterized by progressive visual and visuospatial dysfunction. The consensus criteria state that patients should present "relatively spared behavior and personality" in early stages. However, limited research has focused on these symptoms in PCA. This study compared 157 patients with PCA in early stages of the disease with 352 healthy controls (HC), 202 typical AD (tAD), and 177 logopenic variant primary progressive aphasia (lvPPA) patients from the National Alzheimer's Coordinating Center (NACC) dataset...

Prior research has revealed distinctive patterns of impaired language abilities across the three variants of Primary Progressive Aphasia (PPA): nonfluent/agrammatic (nfvPPA), logopenic (lvPPA) and semantic (svPPA). However, little is known about whether, and to what extent, non-verbal cognitive abilities, such as processing speed, are impacted in PPA patients. This is because neuropsychological tests typically contain linguistic stimuli and require spoken output, being therefore sensitive to verbal deficits in aphasic patients...

Increasing evidence implicates endo-lysosomal dysfunction in frontotemporal dementia (FTD). 18 proteins were quantified using a mass spectrometry assay panel in the cerebrospinal fluid of 36 people with the language variant of FTD, primary progressive aphasia (PPA) (including 13 with non-fluent variant (nfvPPA), 11 with semantic variant (svPPA), and 12 with logopenic variant (lvPPA)) and 19 healthy controls. The concentrations of the cathepsins (B, D, F, L1, and Z) as well as AP-2 complex subunit beta, ganglioside GM2 activator, beta-hexosaminidase subunit beta, tissue alpha L-fucosidase, and ubiquitin were decreased in nfvPPA compared with controls...

We report a 73-year-old woman who started developing recurrent transient aphasia at the age of 66 years. During the attacks, she was aware she could not understand what was being said and both her spoken and written speech were meaningless. The attacks usually lasted for a few days, following which she could explain what had happened. Anti-epileptics did not improve her symptoms. She also noticed tremor of her right hand and gait disturbance at the age of 71 years. The recurrent transient aphasia was followed by drop attacks...

BACKGROUND: In Alzheimer's disease (AD), the gradual accumulation of amyloid-β (Aβ) and tau proteins may underlie alterations in empathy. OBJECTIVE: To assess whether tau aggregation in the medial temporal lobes relates to differences in cognitive empathy (the ability to take others' perspectives) and emotional empathy (the ability to experience others' feelings) in AD. METHODS: Older adults (n = 105) completed molecular Aβ positron emission tomography (PET) scans...

OBJECTIVE: To examine the audiological characteristics and neuroanatomical regions associated with auditory phonological identification impairment in primary progressive aphasia (PPA). METHODS: Twenty-seven patients with PPA [13 non-fluent/agrammatic variant PPA (nfvPPA), three logopenic variant PPA (lvPPA), seven semantic variant PPA (svPPA), and four mixed type PPA] were included in the study. Neuropsychological, language, audiological, and neuroradiological examinations were also performed...

BACKGROUND: Logopenic variant primary progressive aphasia (lvPPA), which is most commonly an early onset variant of Alzheimer's disease (AD), is a progressive impairment in word retrieval and language expression. Clinicians often misdiagnose these patients when they present with severely unintelligible speech consistent with jargonaphasia. METHODS: We reviewed all patients presenting to a behavioral neurology program over a 23-year period who met criteria for lvPPA after completion of an evaluation extending to positron emission tomography (PET) of the brain...

The logopenic variant of primary progressive aphasia (lvPPA) is characterized mainly by anomia, production of phonological errors, and impairment in repetition of sentences. The functional origin of these language impairments is mainly attributed to the breakdown of phonological short-term memory. The present study examined the effects of phonological short-term memory impairment on language processing in lvPPA. In two studies, 11 participants with lvPPA and 11 healthy control participants were presented with repetition tasks in which the type and length of stimuli and the mode of administration were manipulated...

Despite the important role of written language in everyday life, abnormalities in functional written communication have been sparsely investigated in primary progressive aphasia. Prior studies have analysed written language separately in each of the three variants of primary progressive aphasia-but have rarely compared them to each other or to spoken language. Manual analysis of written language can be a time-consuming process. We therefore developed a program that quantifies content units and total units in written or transcribed language samples...

Overlapping clinical presentations in primary progressive aphasia (PPA) variants present challenges for diagnosis and understanding pathophysiology, particularly in the early stages of the disease when behavioral (speech) symptoms are not clearly evident. Divergent atrophy patterns (temporoparietal degeneration in logopenic variant lvPPA, frontal degeneration in nonfluent variant nfvPPA) can partially account for differential speech production errors in the two groups in the later stages of the disease. While the existing dogma states that neurodegeneration is the root cause of compromised behavior and cortical activity in PPA, the extent to which neurophysiological signatures of speech dysfunction manifest independent of their divergent atrophy patterns remain unknown...

Alzheimer-Perusini's (AD) disease represents the most spread dementia around the world and constitutes a serious problem for public health. It was first described by the two physicians from whom it took its name. Nowadays, we have extensively expanded our knowledge about this disease. Starting from a merely clinical and histopathologic description, we have now reached better molecular comprehension. For instance, we passed from an old conceptualization of the disease based on plaques and tangles to a more modern vision of mixed proteinopathy in a one-to-one relationship with an alteration of specific glial and neuronal phenotypes...

INTRODUCTION: Atypical variants of Alzheimer's disease (AD) include the visual variant, known as posterior cortical atrophy (PCA), and the language variant, known as logopenic progressive aphasia (LPA). Clinically, rates of disease progression differ between them. METHODS: We evaluated 34 PCA and 29 LPA participants. Structural magnetic resonance imaging and 18 F-flortaucipir positron emission tomography were performed at baseline and at 1-year follow-up. Rates of change in tau uptake and grey matter volumes were compared between PCA and LPA with linear mixed-effects models and voxel-based analyses...

BACKGROUND: The majority of patients with primary progressive aphasia (PPA) can be distinguished into one of three variants: semantic, non-fluent/agrammatic, or logopenic. However, many do not meet criteria for any one variant. AIM: To identify aspects of cognitive-linguistic performance that yield an early unclassifiable PPA designation that predicted the later emergence of a given variant. METHODS & PROCEDURES: Of 256 individuals with PPA evaluated, 19 initially were unclassifiable and later met criteria for a variant...

PURPOSE OF REVIEW: The aim of this paper is to summarize the latest work on neuroimaging in atypical Alzheimer's disease (AD) patients and to emphasize innovative aspects in the clinic and research. The paper will mostly cover language (logopenic variant of primary progressive aphasia; lvPPA), visual (posterior cortical atrophy; PCA), behavioral (bvAD) and dysexecutive (dAD) variants of AD. RECENT FINDINGS: MRI and PET can detect and differentiate typical and atypical AD variants, and novel imaging markers like brain iron deposition, white matter hyperintensities (WMH), cortical mean diffusivity, and brain total creatine can also contribute...

Agrammatism is a disorder of language production characterized by short, simplified sentences, the omission of function words, an increased use of nouns over verbs and a higher use of heavy verbs. Despite observing these phenomena for decades, the accounts of agrammatism have not converged. Here, we propose and test the hypothesis that the lexical profile of agrammatism results from a process that opts for words with a lower frequency of occurrence to increase lexical information. Furthermore, we hypothesize that this process is a compensatory response to patients' core deficit in producing long, complex sentences...

The logopenic variant of primary progressive aphasia (lvPPA) is a neurodegenerative syndrome characterized linguistically by gradual loss of repetition and naming skills resulting from left posterior temporal and inferior parietal atrophy. Here, we sought to identify which specific cortical loci are initially targeted by the disease (epicenters) and investigate whether atrophy spreads through predetermined networks. First, we used cross-sectional structural MRI data from individuals with lvPPA to define putative disease epicenters using a surface-based approach paired with an anatomically fine-grained parcellation of the cortical surface (i...

The logopenic variant of primary progressive aphasia (lvPPA) is a neurodegenerative syndrome characterized linguistically by gradual loss of repetition and naming skills, resulting from left posterior temporal and inferior parietal atrophy. Here, we sought to identify which specific cortical loci are initially targeted by the disease (epicenters) and investigate whether atrophy spreads through pre-determined networks. First, we used cross-sectional structural MRI data from individuals with lvPPA to define putative disease epicenters using a surface-based approach paired with an anatomically-fine-grained parcellation of the cortical surface (i...

Successful communication in daily life depends on accurate decoding of speech signals that are acoustically degraded by challenging listening conditions. This process presents the brain with a demanding computational task that is vulnerable to neurodegenerative pathologies. However, despite recent intense interest in the link between hearing impairment and dementia, comprehension of acoustically degraded speech in these diseases has been little studied. Here we addressed this issue in a cohort of 19 patients with typical Alzheimer's disease and 30 patients representing the three canonical syndromes of primary progressive aphasia (nonfluent/agrammatic variant primary progressive aphasia; semantic variant primary progressive aphasia; logopenic variant primary progressive aphasia), compared to 25 healthy age-matched controls...