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Open Access 01-12-2024 | Aphasia | Research

Heterogeneity and overlap in the continuum of linguistic profile of logopenic and semantic variants of primary progressive aphasia: a Profile Analysis based on Multidimensional Scaling study

Authors: Gaia Chiara Santi, Francesca Conca, Valentina Esposito, Cristina Polito, Silvia Paola Caminiti, Cecilia Boccalini, Carmen Morinelli, Valentina Berti, Salvatore Mazzeo, Valentina Bessi, Alessandra Marcone, Sandro Iannaccone, Se-Kang Kim, Sandro Sorbi, Daniela Perani, Stefano F. Cappa, Eleonora Catricalà

Published in: Alzheimer's Research & Therapy | Issue 1/2024

Abstract

Background

Primary progressive aphasia (PPA) diagnostic criteria underestimate the complex presentation of semantic (sv) and logopenic (lv) variants, in which symptoms partially overlap, and mixed clinical presentation (mixed-PPA) and heterogenous profile (lvPPA +) are frequent. Conceptualization of similarities and differences of these clinical conditions is still scarce.

Methods

Lexical, semantic, phonological, and working memory errors from nine language tasks of sixty-seven PPA were analyzed using Profile Analysis based on Multidimensional Scaling, which allowed us to create a distributed representation of patients’ linguistic performance in a shared space. Patients had been studied with [¹⁸F] FDG-PET. Correlations were performed between metabolic and behavioral data.

Results

Patients’ profiles were distributed across a continuum. All PPA, but two, presented a lexical retrieval impairment, in terms of reduced production of verbs and nouns. svPPA patients occupied a fairly clumped space along the continuum, showing a preponderant semantic deficit, which correlated to fusiform gyrus hypometabolism, while only few presented working memory deficits. Adjacently, lvPPA + presented a semantic impairment combined with phonological deficits, which correlated with metabolism in the anterior fusiform gyrus and posterior middle temporal gyrus. Starting from the shared phonological deficit side, a large portion of the space was occupied by all lvPPA, showing a combination of phonological, lexical, and working memory deficits, with the latter correlating with posterior temporo-parietal hypometabolism. Mixed PPA did not show unique profile, distributing across the space.

Discussion

Different clinical PPA entities exist but overlaps are frequent. Identifying shared and unique clinical markers is critical for research and clinical practice. Further research is needed to identify the role of genetic and pathological factors in such distribution, including also higher sample size of less represented groups.

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Title: Heterogeneity and overlap in the continuum of linguistic profile of logopenic and semantic variants of primary progressive aphasia: a Profile Analysis based on Multidimensional Scaling study
Authors: Gaia Chiara Santi
Francesca Conca
Valentina Esposito
Cristina Polito
Silvia Paola Caminiti
Cecilia Boccalini
Carmen Morinelli
Valentina Berti
Salvatore Mazzeo
Valentina Bessi
Alessandra Marcone
Sandro Iannaccone
Se-Kang Kim
Sandro Sorbi
Daniela Perani
Stefano F. Cappa
Eleonora Catricalà
Publication date: 01-12-2024
Publisher: BioMed Central
Keyword: Aphasia
Published in: Alzheimer's Research & Therapy / Issue 1/2024
Electronic ISSN: 1758-9193
DOI: https://doi.org/10.1186/s13195-024-01403-0

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Heterogeneity and overlap in the continuum of linguistic profile of logopenic and semantic variants of primary progressive aphasia: a Profile Analysis based on Multidimensional Scaling study

Abstract

Background

Methods

Results

Discussion

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Abstract

Background

Methods

Results

Discussion

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