Phonological Errors in Posterior Cortical Atrophy

2021 ◽  
pp. 1-9
Author(s):  
Katerina A. Tetzloff ◽  
Joseph R. Duffy ◽  
Edythe A. Strand ◽  
Mary M. Machulda ◽  
Christopher G. Schwarz ◽  
...  
Keyword(s):  
Clinical Symptoms ◽  
Primary Progressive Aphasia ◽  
Brain Regions ◽  
Cortical Atrophy ◽  
Posterior Cortical Atrophy ◽  
Boston Naming Test ◽  
Language Tests ◽  
Language Difficulties ◽  
Phonological Errors ◽  
Gray Matter Volumes

<b><i>Background:</i></b> Posterior cortical atrophy (PCA) is an atypical variant of Alzheimer’s disease (AD) that presents with visuospatial/perceptual deficits. PCA is characterized by atrophy in posterior brain regions, which overlaps with atrophy occurring in logopenic variant of primary progressive aphasia (lvPPA), another atypical AD variant characterized by language difficulties, including phonological errors. Language abnormalities have been observed in PCA, although the prevalence of phonological errors is unknown. We aimed to compare the frequency and severity of phonological errors in PCA and lvPPA and determine the neuroanatomical correlates of phonological errors and language abnormalities in PCA. <b><i>Methods:</i></b> The presence and number of phonological errors were recorded during the Boston Naming Test and Western Aphasia Battery repetition subtest in 27 PCA patients and 27 age- and disease duration-matched lvPPA patients. Number of phonological errors and scores from language tests were correlated with regional gray matter volumes using Spearman correlations. <b><i>Results:</i></b> Phonological errors were evident in 55% of PCA patients and 70% of lvPPA patients, with lvPPA having higher average number of errors. Phonological errors in PCA correlated with decreased left inferior parietal and lateral temporal volume. Naming and fluency were also associated with decreased left lateral temporal lobe volume. <b><i>Conclusions:</i></b> Phonological errors are common in PCA, although they are not as prevalent or severe as in lvPPA, and they are related to involvement of left temporoparietal cortex. This highlights the broad spectrum of clinical symptoms associated with AD and overlap between PCA and lvPPA.

Difficulties in diagnosing atypical variants of Alzheimer’s disease

2021 ◽  
Vol 26 (5) ◽  
pp. 16-23
Author(s):  
A. A. Tappakhov ◽  
T. Ya. Nikolaeva ◽  
T. E. Popova ◽  
N. A. Shnayder
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Clinical Picture ◽  
Short Term Memory ◽  
Late Onset ◽  
Early Stage ◽  
Primary Progressive Aphasia ◽  
Cortical Atrophy ◽  
Posterior Cortical Atrophy ◽  
Short Term

Alzheimer’s disease (AD) is the most common cause of dementia in the population. Late onset AD has a classic clinical picture with short-term memory deficit, apraxia and agnosia. Patients with early-onset AD may have an atypical clinical picture which complicates diagnosis. Atypical AD variants include the logopenic variant of primary progressive aphasia, posterior cortical atrophy, behavioral, biparietal, and cortico-basal variants. These variants have pathomorphological signs similar to classical AD, but at an early stage they are characterized by focal atrophy which explains their clinical polymorphism. This article provides a review of the current literature on atypical types of AD and presents a clinical case of a 62-year-old patient in whom the disease debuted with prosopagnosia due to focal atrophy of the temporo-occipital regions of the non-dominant hemisphere.

scholarly journals The Difficult Diagnosis of Posterior Cortical Atrophy in a 62-Year-Old Woman

2019 ◽  
Vol 33 (1) ◽  
pp. 59-64
Author(s):  
Georg C. Ziegler ◽  
Axel Haarmann ◽  
Christine Daniels ◽  
Alexandra Herr
Keyword(s):  
Health Care Professionals ◽  
Brain Regions ◽  
Cortical Atrophy ◽  
Csf Biomarkers ◽  
Symptom Presentation ◽  
Imaging Data ◽  
Posterior Cortical Atrophy ◽  
Considerable Uncertainty ◽  
Affective Symptoms ◽  
Diagnostic Difficulties

Posterior cortical atrophy (PCA) describes a rare heterogenous neurodegenerative syndrome with early visuospatial and visuoperceptual deficits due to atrophy of parieto-occipital brain regions. Here, we describe the case of a 62-year-old woman showing severe cognitive impairments as well as hemianopsia and all core symptoms of Bálint's syndrome. Years ago, the patient had complained about a “tunnel view” and concentration problems. The diagnostic results point to a case of PCA with underlying Alzheimer pathology. The disease course until diagnosis lasted for 7 years, reflecting the diagnostic difficulties with this still largely unknown syndrome. The unfamiliar symptom presentation including fluctuations in cognitive performance, affective symptoms, cerebrospinal fluid (CSF) biomarkers, which were at first inconspicuous, and a former suspected diagnosis of dissociative pseudodementia, altogether brought considerable uncertainty to the involved health-care professionals. We conclude that cases of “atypical dementia” presenting with visual symptoms, even if appearing unspecific at first, are suspect of PCA. This case report provides an ostensive overview of PCA, including imaging data, CSF-findings, original drawings and handwriting samples from the patient.

scholarly journals What’s “up”? Impaired Spatial Preposition Processing in Posterior Cortical Atrophy

2021 ◽  
Vol 15 ◽  
Author(s):  
Zubaida Shebani ◽  
Peter J. Nestor ◽  
Friedemann Pulvermüller
Keyword(s):  
Serial Recall ◽  
Semantic Processing ◽  
Memory Performance ◽  
Strong Support ◽  
Case Series ◽  
Brain Regions ◽  
Cortical Atrophy ◽  
Posterior Cortical Atrophy ◽  
Atypical Form ◽  
Spatial Prepositions

This study seeks to confirm whether lesions in posterior regions of the brain involved in visuo-spatial processing are of functional relevance to the processing of words with spatial meaning. We investigated whether patients with Posterior Cortical Atrophy (PCA), an atypical form of Alzheimer’s Disease which predominantly affects parieto-occipital brain regions, is associated with deficits in working memory for spatial prepositions. Case series of patients with PCA and matched healthy controls performed tests of immediate and delayed serial recall on words from three lexico-semantic word categories: number words (twelve), spatial prepositions (behind) and function words (e.g., shall). The three word categories were closely matched for a number of psycholinguistic and semantic variables including length, bi-/tri-gram frequency, word frequency, valence and arousal. Relative to controls, memory performance of PCA patients on short word lists was significantly impaired on spatial prepositions in the delayed serial recall task. These results suggest that lesions in posterior parieto-occipital regions specifically impair the processing of spatial prepositions. Our findings point to a pertinent role of posterior cortical regions in the semantic processing of words with spatial meaning and provide strong support for modality-specific semantic theories that recognize the necessary contributions of sensorimotor regions to conceptual semantic processing.

scholarly journals COGNITIVE MEASURE MAY IDENTIFY ATROPHY IN BRAIN REGIONS ASSOCIATED WITH POSTERIOR CORTICAL ATROPHY

2017 ◽  
Vol 1 (suppl_1) ◽  
pp. 587-587
Author(s):  
E. Couser ◽  
M. Albert ◽  
C. Pettigrew ◽  
A. Soldan
Keyword(s):  
Brain Regions ◽  
Cortical Atrophy ◽  
Posterior Cortical Atrophy ◽  
Cognitive Measure

scholarly journals Tau filaments from multiple cases of sporadic and inherited Alzheimer’s disease adopt a common fold

2018 ◽  
Author(s):  
Benjamin Falcon ◽  
Wenjuan Zhang ◽  
Manuel Schweighauser ◽  
Alexey G. Murzin ◽  
Ruben Vidal ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Frontal Cortex ◽  
Paired Helical Filaments ◽  
Brain Regions ◽  
Cortical Atrophy ◽  
Posterior Cortical Atrophy ◽  
Negative Stain ◽  
Negative Stain Electron Microscopy ◽  
Ordered Assembly

AbstractThe ordered assembly of tau protein into abnormal filaments is a defining characteristic of Alzheimer’s disease (AD) and other neurodegenerative disorders. It is not known if the structures of tau filaments vary within, or between, the brains of individuals with AD. We used a combination of electron cryo-microscopy (cryo-EM) and immuno-gold negative-stain electron microscopy (immuno-EM) to determine the structures of paired helical filaments (PHFs) and straight filaments (SFs) from the frontal cortex of 17 cases of typical AD (15 sporadic and 2 inherited) and 2 cases of atypical AD (posterior cortical atrophy). The high-resolution structures of PHFs and SFs from the frontal cortex of 3 cases of typical AD, 2 sporadic and 1 inherited, were determined by cryo-EM. We also used immuno-EM to study the PHFs and SFs from a number of cortical and subcortical brain regions. PHFs outnumbered SFs in all AD cases. By cryo-EM, PHFs and SFs were made of two C-shaped protofilaments with a combined cross-β/β-helix structure, as described previously for a case of AD. The higher resolution structures obtained here showed two additional amino acids at each end of the protofilament structure. The immuno-EM findings, which established the presence of repeats 3 and 4, but not repeats 1 and 2, of tau in the filament cores of all AD cases and brain regions thereof, were consistent with the cryo-EM results. These findings show that there is no significant variation in tau filament structures between individuals with AD. This knowledge will be crucial for understanding the mechanisms that underlie tau filament formation and for developing novel diagnostics and therapies.

scholarly journals 18F–THK–5351, Fluorodeoxyglucose, and Florbetaben PET Images in Atypical Alzheimer’s Disease: A Pictorial Insight into Disease Pathophysiology

2021 ◽  
Vol 11 (4) ◽  
pp. 465
Author(s):  
Sohee Park ◽  
Minyoung Oh ◽  
Jae Kim ◽  
Jae-Hong Lee ◽  
Young Yoon ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Clinical Symptoms ◽  
Primary Progressive Aphasia ◽  
Clinical Findings ◽  
Cortical Atrophy ◽  
Positron Emission ◽  
Clinical Presentations ◽  
Atypical Alzheimer’S Disease ◽  
Insight Into

The recent advance of positron emission tomography (PET) tracers as biomarkers in Alzheimer’s disease (AD) provides more insight into pathophysiology, preclinical diagnosis, and further therapeutic strategies. However, synergistic processes or interactions between amyloid and tau deposits are still poorly understood. To better understand their relationship in focal brain changes with clinical phenotypes, we focused on region-specific or atypical AD characterized by focal clinical presentations: Posterior cortical atrophy (PCA) and logopenic variant of primary progressive aphasia (lpvPPA). We compared three different PET images with 18F–THK–5351 (tau), 18F–Florbetaben (amyloid beta, Aβ), and 18F–Fluorodeoxyglucose (glucose metabolism) to investigate potential interactions among pathologies and clinical findings. Whereas the amyloid accumulations were widespread throughout the neocortex, tau retentions and glucose hypometabolism showed focal changes corresponding to the clinical features. The distinctly localized patterns were more prominent in tau PET imaging. These findings suggest that tau pathology correlates more closely to the clinical symptoms and the neurodegenerative processes than Aβ pathology in AD.

Sign in / Sign up

Export Citation Format

Share Document