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Ding J, Mirman D. Data-driven classification of narrative speech characteristics in stroke aphasia distinguishes neurological and strategic contributions. Cortex 2025; 186:61-73. [PMID: 40186929 DOI: 10.1016/j.cortex.2025.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2024] [Revised: 03/19/2025] [Accepted: 03/19/2025] [Indexed: 04/07/2025]
Abstract
Narrative speech deficits are common in post-stroke aphasia, resulting in negative influences on social participation and quality of life. Speech rate, complexity, and informativeness deficits all contribute to narrative speech. Research studies typically (implicitly) assume that these aspects of narrative speech production are a result of cognitive/neurological impairment, but they may also result from strategic choices made as individuals with aphasia attempt to produce narrative speech. Here, we used data-driven methods to classify aphasic narrative speech patterns and evaluated their predictability from lesion patterns. 76 stroke aphasia patients completed 11 narrative speech production tasks. Quantitative Production Analysis (QPA) and Correct Information Unit (CIU) analysis were used to measure their structural and functional properties. Based on prior work, we selected QPA measures of speech rate (words per minute) and complexity (mean sentence length, inflection index, and auxiliary index) and four CIU measures of informativeness (#CIU, CIU/min, %CIU, #nonCIU). These measures produced two orthogonal dimensions with four orthogonal participant clusters. Comprehensive comparison between clusters revealed that speech rate and complexity were strongly associated with general aphasia severity and total lesion volume, and were predicted by frontoparietal grey matter and dorsal pathway white matter damage. In contrast, informativeness was independent of other behavioral and neurological deficits, and was not predictable from lesion patterns, suggesting that it reflects communication strategy rather than specific neurological impairment. These results provide an important step toward distinguishing neurological and strategic aspects of narrative speech deficits in post-stroke aphasia, with potential implications for treatment approaches that target communication strategies.
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Affiliation(s)
- Junhua Ding
- State Key Laboratory of Cognitive Science and Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
| | - Daniel Mirman
- Department of Psychology, University of Edinburgh, Edinburgh, UK.
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2
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Ramanan S, Akarca D, Henderson SK, Rouse MA, Allinson K, Patterson K, Rowe JB, Lambon Ralph MA. The graded multidimensional geometry of phenotypic variation and progression in neurodegenerative syndromes. Brain 2025; 148:448-466. [PMID: 39018014 PMCID: PMC11788217 DOI: 10.1093/brain/awae233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 05/29/2024] [Accepted: 06/17/2024] [Indexed: 07/18/2024] Open
Abstract
Clinical variants of Alzheimer's disease and frontotemporal lobar degeneration display a spectrum of cognitive-behavioural changes varying between individuals and over time. Understanding the landscape of these graded individual/group level longitudinal variations is critical for precise phenotyping; however, this remains challenging to model. Addressing this challenge, we leverage the National Alzheimer's Coordinating Center database to derive a unified geometric framework of graded longitudinal phenotypic variation in Alzheimer's disease and frontotemporal lobar degeneration. We included three time point, cognitive-behavioural and clinical data from 390 typical, atypical and intermediate Alzheimer's disease and frontotemporal lobar degeneration variants (114 typical Alzheimer's disease; 107 behavioural variant frontotemporal dementia; 42 motor variants of frontotemporal lobar degeneration; and 103 primary progressive aphasia patients). On these data, we applied advanced data-science approaches to derive low-dimensional geometric spaces capturing core features underpinning clinical progression of Alzheimer's disease and frontotemporal lobar degeneration syndromes. To do so, we first used principal component analysis to derive six axes of graded longitudinal phenotypic variation capturing patient-specific movement along and across these axes. Then, we distilled these axes into a visualizable 2D manifold of longitudinal phenotypic variation using Uniform Manifold Approximation and Projection. Both geometries together enabled the assimilation and interrelation of paradigmatic and mixed cases, capturing dynamic individual trajectories and linking syndromic variability to neuropathology and key clinical end points, such as survival. Through these low-dimensional geometries, we show that (i) specific syndromes (Alzheimer's disease and primary progressive aphasia) converge over time into a de-differentiated pooled phenotype, while others (frontotemporal dementia variants) diverge to look different from this generic phenotype; (ii) phenotypic diversification is predicted by simultaneous progression along multiple axes, varying in a graded manner between individuals and syndromes; and (iii) movement along specific principal axes predicts survival at 36 months in a syndrome-specific manner and in individual pathological groupings. The resultant mapping of dynamics underlying cognitive-behavioural evolution potentially holds paradigm-changing implications to predicting phenotypic diversification and phenotype-neurobiological mapping in Alzheimer's disease and frontotemporal lobar degeneration.
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Affiliation(s)
- Siddharth Ramanan
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
| | - Danyal Akarca
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
| | - Shalom K Henderson
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
- Department of Clinical Neurosciences and Cambridge University Hospitals NHS Trust, University of Cambridge, Cambridge CB2 0SZ, UK
| | - Matthew A Rouse
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
| | - Kieren Allinson
- Department of Clinical Neurosciences and Cambridge University Hospitals NHS Trust, University of Cambridge, Cambridge CB2 0SZ, UK
- Department of Pathology, Cambridge University Hospitals NHS Trust, Cambridge CB2 1QP, UK
| | - Karalyn Patterson
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
- Department of Clinical Neurosciences and Cambridge University Hospitals NHS Trust, University of Cambridge, Cambridge CB2 0SZ, UK
| | - James B Rowe
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
- Department of Clinical Neurosciences and Cambridge University Hospitals NHS Trust, University of Cambridge, Cambridge CB2 0SZ, UK
| | - Matthew A Lambon Ralph
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
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Xi Y, Abuduxiku M, Qu M. GRN knockdown regulates the expression and alternative splicing of genes associated with aphasia-related diseases in PC12 cells. Brain Res 2024; 1840:149031. [PMID: 38823507 DOI: 10.1016/j.brainres.2024.149031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 05/15/2024] [Accepted: 05/25/2024] [Indexed: 06/03/2024]
Abstract
BACKGROUND Prior research has shown that granulin precursor (GRN, also termed PGRN) is closely linked to aphasia. However, there has been little research on the mechanism of action of GRN in post-stroke aphasia (PSA). METHODS In this study, RT-qPCR was used to identify variations in gene expression, while RNA sequencing (RNA-seq) was utilized to acquire transcriptional profiles. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases were employed for bioinformatics analysis. RESULTS GRN was considerably more active in PSA subjects. After silencing the GRN, 197 transcripts had differential expression, and 237 alternative splicing events (ASEs) were substantially affected. The analysis of differentially expressed genes (DEGs) using GO and KEGG approaches showed that these genes have various molecular functions and are significantly enriched in metabolic signaling pathways. Regarding Alternative Splicing (AS), the GO and KEGG analyses revealed numerous functional genes involved in transcription and metabolism. CONCLUSIONS The knockdown of GRN has been shown to be associated with alterations in transcription, metabolism, and ASEs, potentially impacting transcriptional and metabolic pathways through its involvement in AS. Furthermore, GRN knockdown is associated with nervous system disease-related gene transcription and AS processes, as well as its involvement in G protein-coupled receptor (GPCR) and wingless/integrated (Wnt) signaling pathways, which impact the initiation and resolution of PSA.
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Affiliation(s)
- Yanling Xi
- Department of Rehabilitation Medicine, Shanghai Pudong New Area Guangming Hospital of Traditional Chinese Medicine, China
| | - Munire Abuduxiku
- Department of Rehabilitation Medicine, The Affiliated Hospital of Traditional Chinese Medicine of Xinjiang Medical University, China
| | - Mei Qu
- Department of Rehabilitation Medicine, Shanghai Pudong New Area Guangming Hospital of Traditional Chinese Medicine, China.
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Rezaii N, Hochberg D, Quimby M, Wong B, Brickhouse M, Touroutoglou A, Dickerson BC, Wolff P. Artificial intelligence classifies primary progressive aphasia from connected speech. Brain 2024; 147:3070-3082. [PMID: 38912855 PMCID: PMC11370793 DOI: 10.1093/brain/awae196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 05/08/2024] [Accepted: 05/21/2024] [Indexed: 06/25/2024] Open
Abstract
Neurodegenerative dementia syndromes, such as primary progressive aphasias (PPA), have traditionally been diagnosed based, in part, on verbal and non-verbal cognitive profiles. Debate continues about whether PPA is best divided into three variants and regarding the most distinctive linguistic features for classifying PPA variants. In this cross-sectional study, we initially harnessed the capabilities of artificial intelligence and natural language processing to perform unsupervised classification of short, connected speech samples from 78 pateints with PPA. We then used natural language processing to identify linguistic features that best dissociate the three PPA variants. Large language models discerned three distinct PPA clusters, with 88.5% agreement with independent clinical diagnoses. Patterns of cortical atrophy of three data-driven clusters corresponded to the localization in the clinical diagnostic criteria. In the subsequent supervised classification, 17 distinctive features emerged, including the observation that separating verbs into high- and low-frequency types significantly improved classification accuracy. Using these linguistic features derived from the analysis of short, connected speech samples, we developed a classifier that achieved 97.9% accuracy in classifying the four groups (three PPA variants and healthy controls). The data-driven section of this study showcases the ability of large language models to find natural partitioning in the speech of patients with PPA consistent with conventional variants. In addition, the work identifies a robust set of language features indicative of each PPA variant, emphasizing the significance of dividing verbs into high- and low-frequency categories. Beyond improving diagnostic accuracy, these findings enhance our understanding of the neurobiology of language processing.
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Affiliation(s)
- Neguine Rezaii
- Frontotemporal Disorders Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Daisy Hochberg
- Frontotemporal Disorders Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Megan Quimby
- Frontotemporal Disorders Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Bonnie Wong
- Frontotemporal Disorders Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Michael Brickhouse
- Frontotemporal Disorders Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Alexandra Touroutoglou
- Frontotemporal Disorders Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
- Department of Psychology, Emory University, Atlanta, GA 30322, USA
| | - Bradford C Dickerson
- Frontotemporal Disorders Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Harvard Medical School, Boston, MA 02129, USA
- Massachusetts Alzheimer's Disease Research Center, Harvard Medical School, Boston, MA 02114, USA
| | - Phillip Wolff
- Department of Psychology, Emory University, Atlanta, GA 30322, USA
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Ingram RU, Ocal D, Halai A, Pobric G, Cash DM, Crutch S, Yong KX, Lambon Ralph MA. Graded Multidimensional Clinical and Radiologic Variation in Patients With Alzheimer Disease and Posterior Cortical Atrophy. Neurology 2024; 103:e209679. [PMID: 39042846 PMCID: PMC11314952 DOI: 10.1212/wnl.0000000000209679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 05/17/2024] [Indexed: 07/25/2024] Open
Abstract
BACKGROUND AND OBJECTIVES Alzheimer disease (AD) spans heterogeneous typical and atypical phenotypes. Posterior cortical atrophy (PCA) is a striking example, characterized by prominent impairment in visual and other posterior functions in contrast to typical, amnestic AD. The primary study objective was to establish how the similarities and differences of cognition and brain volumes within AD and PCA (and by extension other AD variants) can be conceptualized as systematic variations across a transdiagnostic, graded multidimensional space. METHODS This was a cross-sectional, single-center, observational, cohort study performed at the National Hospital for Neurology & Neurosurgery, London, United Kingdom. Data were collected from a cohort of patients with PCA and AD, matched for age, disease duration, and Mini-Mental State Examination (MMSE) scores. There were 2 sets of outcome measures: (1) scores on a neuropsychological battery containing 22 tests spanning visuoperceptual and visuospatial processing, episodic memory, language, executive functions, calculation, and visuospatial processing and (2) measures extracted from high-resolution T1-weighted volumetric MRI scans. Principal component analysis was used to extract the transdiagnostic dimensions of phenotypical variation from the detailed neuropsychological data. Voxel-based morphometry was used to examine associations between the PCA-derived clinical phenotypes and the structural measures. RESULTS We enrolled 93 participants with PCA (mean: age = 59.9 years, MMSE = 21.2; 59/93 female) and 58 AD participants (mean: age = 57.1 years, MMSE = 19.7; 22/58 female). The principal component analysis for PCA (sample adequacy confirmed: Kaiser-Meyer-Olkin = 0.865) extracted 3 dimensions accounting for 61.0% of variance in patients' performance, reflecting general cognitive impairment, visuoperceptual deficits, and visuospatial impairments. Plotting AD cases into the PCA-derived multidimensional space, and vice versa, revealed graded, overlapping variations between cases along these dimensions, with no evidence for categorical-like patient clustering. Similarly, the relationship between brain volumes and scores on the extracted dimensions was overlapping for PCA and AD cases. DISCUSSION These results provide evidence supporting a reconceptualization of clinical and radiologic variation in these heterogenous AD phenotypes as being along shared phenotypic continua spanning PCA and AD, arising from systematic graded variations within a transdiagnostic, multidimensional neurocognitive geometry.
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Affiliation(s)
- Ruth U Ingram
- From the Division of Psychology and Mental Health (R.U.I., G.P.), University of Manchester; Dementia Research Centre (D.O., D.M.C., S.C., K.X.Y.), UCL Institute of Neurology, London; and MRC Cognition and Brain Sciences Unit (A.H., M.A.L.R.), University of Cambridge, United Kingdom
| | - Dilek Ocal
- From the Division of Psychology and Mental Health (R.U.I., G.P.), University of Manchester; Dementia Research Centre (D.O., D.M.C., S.C., K.X.Y.), UCL Institute of Neurology, London; and MRC Cognition and Brain Sciences Unit (A.H., M.A.L.R.), University of Cambridge, United Kingdom
| | - Ajay Halai
- From the Division of Psychology and Mental Health (R.U.I., G.P.), University of Manchester; Dementia Research Centre (D.O., D.M.C., S.C., K.X.Y.), UCL Institute of Neurology, London; and MRC Cognition and Brain Sciences Unit (A.H., M.A.L.R.), University of Cambridge, United Kingdom
| | - Gorana Pobric
- From the Division of Psychology and Mental Health (R.U.I., G.P.), University of Manchester; Dementia Research Centre (D.O., D.M.C., S.C., K.X.Y.), UCL Institute of Neurology, London; and MRC Cognition and Brain Sciences Unit (A.H., M.A.L.R.), University of Cambridge, United Kingdom
| | - David M Cash
- From the Division of Psychology and Mental Health (R.U.I., G.P.), University of Manchester; Dementia Research Centre (D.O., D.M.C., S.C., K.X.Y.), UCL Institute of Neurology, London; and MRC Cognition and Brain Sciences Unit (A.H., M.A.L.R.), University of Cambridge, United Kingdom
| | - Sebastian Crutch
- From the Division of Psychology and Mental Health (R.U.I., G.P.), University of Manchester; Dementia Research Centre (D.O., D.M.C., S.C., K.X.Y.), UCL Institute of Neurology, London; and MRC Cognition and Brain Sciences Unit (A.H., M.A.L.R.), University of Cambridge, United Kingdom
| | - Keir X Yong
- From the Division of Psychology and Mental Health (R.U.I., G.P.), University of Manchester; Dementia Research Centre (D.O., D.M.C., S.C., K.X.Y.), UCL Institute of Neurology, London; and MRC Cognition and Brain Sciences Unit (A.H., M.A.L.R.), University of Cambridge, United Kingdom
| | - Matthew A Lambon Ralph
- From the Division of Psychology and Mental Health (R.U.I., G.P.), University of Manchester; Dementia Research Centre (D.O., D.M.C., S.C., K.X.Y.), UCL Institute of Neurology, London; and MRC Cognition and Brain Sciences Unit (A.H., M.A.L.R.), University of Cambridge, United Kingdom
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Ding J, Yang Q, Drossinos N, Guo Q. Advances in semantic dementia: Neuropsychology, pathology & neuroimaging. Ageing Res Rev 2024; 99:102375. [PMID: 38866186 DOI: 10.1016/j.arr.2024.102375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 06/03/2024] [Accepted: 06/04/2024] [Indexed: 06/14/2024]
Abstract
Semantic dementia is a kind of neurodegenerative disorder, characterized by prominent semantic impairments and anterior temporal lobe atrophy. Since 2010, more studies have devoted to this rare disorder, revealing that it is more complex than we think. Clinical advances include more specific findings of semantic impairments and other higher order cognitive deficits. Neuroimaging techniques can help revealing the different brain networks affected (both structurally and functionally) in this condition. Pathological and genetic studies have also found more complex situations of semantic dementia, which might explain the huge variance existing in semantic dementia. Moreover, the current diagnosis criteria mainly focus on semantic dementia's classical prototype. We further delineated the features of three subtypes of semantic dementia based on atrophy lateralization with three severity stages. In a broader background, as a part of the continuum of neurodegenerative disorders, semantic dementia is commonly compared with other resembling conditions. Therefore, we summarized the differential diagnosis between semantic dementia and them. Finally, we introduced the challenges and achievements of its diagnosis, treatment, care and cross cultural comparison. By providing a comprehensive picture of semantic dementia on different aspects of advances, we hope to deepen the understanding of semantic dementia and promote more inspirations on both clinical and theoretical studies about it.
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Affiliation(s)
- Junhua Ding
- Department of Gerontology, Shanghai Sixth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Department of Psychology, University of Edinburgh, Edinburgh, UK
| | - Qing Yang
- Department of Rehabilitation, Hushan Hospital, Fudan University, Shanghai, China
| | - Niki Drossinos
- Division of Psychology, Communication and Human Neuroscience, University of Manchester, Manchester, UK
| | - Qihao Guo
- Department of Gerontology, Shanghai Sixth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
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Cordella C, Di Filippo L, Kolachalama VB, Kiran S. Connected Speech Fluency in Poststroke and Progressive Aphasia: A Scoping Review of Quantitative Approaches and Features. AMERICAN JOURNAL OF SPEECH-LANGUAGE PATHOLOGY 2024; 33:2091-2128. [PMID: 38652820 PMCID: PMC11253646 DOI: 10.1044/2024_ajslp-23-00208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 10/09/2023] [Accepted: 01/08/2024] [Indexed: 04/25/2024]
Abstract
PURPOSE Speech fluency has important diagnostic implications for individuals with poststroke aphasia (PSA) as well as primary progressive aphasia (PPA), and quantitative assessment of connected speech has emerged as a widely used approach across both etiologies. The purpose of this review was to provide a clearer picture on the range, nature, and utility of individual quantitative speech/language measures and methods used to assess connected speech fluency in PSA and PPA, and to compare approaches across etiologies. METHOD We conducted a scoping review of literature published between 2012 and 2022 following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidelines. Forty-five studies were included in the review. Literature was charted and summarized by etiology and characteristics of included patient populations and method(s) used for derivation and analysis of speech/language features. For a subset of included articles, we also charted the individual quantitative speech/language features reported and the level of significance of reported results. RESULTS Results showed that similar methodological approaches have been used to quantify connected speech fluency in both PSA and PPA. Two hundred nine individual speech-language features were analyzed in total, with low levels of convergence across etiology on specific features but greater agreement on the most salient features. The most useful features for differentiating fluent from nonfluent aphasia in both PSA and PPA were features related to overall speech quantity, speech rate, or grammatical competence. CONCLUSIONS Data from this review demonstrate the feasibility and utility of quantitative approaches to index connected speech fluency in PSA and PPA. We identified emergent trends toward automated analysis methods and data-driven approaches, which offer promising avenues for clinical translation of quantitative approaches. There is a further need for improved consensus on which subset of individual features might be most clinically useful for assessment and monitoring of fluency. SUPPLEMENTAL MATERIAL https://doi.org/10.23641/asha.25537237.
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Affiliation(s)
- Claire Cordella
- Department of Speech, Language and Hearing Sciences, Boston University, MA
| | - Lauren Di Filippo
- Department of Speech, Language and Hearing Sciences, Boston University, MA
| | - Vijaya B. Kolachalama
- Department of Medicine, Boston University Chobanian & Avedisian School of Medicine, MA
- Department of Computer Science and Faculty of Computing & Data Sciences, Boston University, MA
| | - Swathi Kiran
- Department of Speech, Language and Hearing Sciences, Boston University, MA
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Ossewaarde R, Pijnenburg Y, Keulen A, Jonkers R, Leijnen S. Role of pause duration in primary progressive aphasia. APHASIOLOGY 2024; 39:601-619. [PMID: 40303008 PMCID: PMC12036531 DOI: 10.1080/02687038.2024.2366285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Accepted: 06/06/2024] [Indexed: 05/02/2025]
Abstract
Aims To detect differences in speech fluency in separate primary progressive aphasia syndromes (PPA) using automated analysis techniques. The resulting linguistic features are evaluated for their use in a predictive model to identify common patterns in speakers with PPA. As fluency is observable in audio recordings, its quantification may provide a low-cost instrument that augments spontaneous speech analyses in clinical practice. Methods and Procedures Speech was recorded in 14 controls, 7 nonfluent variant (nfvPPA) and 8 semantic variant (svPPA) speakers. The recordings were annotated for speech and non-speech with Kaldi, a common toolkit for speech processing software. Variables relating to fluency (pause rate, number of pauses, length of pauses) were analyzed. Outcomes and Results The best fitting distribution of pause duration was a combination of two Gaussian distributions, corresponding with pause categories short vs. long.Group level differences were found in the rate of pauses and proportion of silence: nfvPPA speakers use more short pauses relative to long pauses than control speakers, and the duration of short and long pauses is longer; svPPA speakers use more longer pauses relative to short pauses. Their short pauses are significantly shorter than those from control speakers.Participants in both PPA groups pause more frequently. SvPPA speakers are typically perceived as fluent. However, our analysis shows their fluency patterns to be distinct from control speakers, if the long-short distinction is observed. Conclusions Automatic measurements of pause duration show meaningful distinctions across the groups and might provide future aid in clinical assessment.
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Affiliation(s)
- Roelant Ossewaarde
- Center for Language and Cognition, Research School for Behavioral and Cognitive Neurosciences, University of Groningen, Groningen, The Netherlands
- Institute for ICT, HU University of Applied Science, Utrecht, The Netherlands
- Alzheimercentrum UMC Amsterdam, Neurology, Amsterdam, The Netherlands
| | | | - Antoinette Keulen
- Alzheimercentrum UMC Amsterdam, Neurology, Amsterdam, The Netherlands
| | - Roel Jonkers
- Center for Language and Cognition, Research School for Behavioral and Cognitive Neurosciences, University of Groningen, Groningen, The Netherlands
| | - Stefan Leijnen
- Institute for ICT, HU University of Applied Science, Utrecht, The Netherlands
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Mazzeo S, Morinelli C, Polito C, Giacomucci G, Moschini V, Ingannato A, Balestrini J, Frigerio D, Emiliani F, Galdo G, Crucitti C, Piazzesi D, Bagnoli S, Padiglioni S, Berti V, Sorbi S, Nacmias B, Bessi V. Data-driven subtypes of mixed semantic-logopenic primary progressive aphasia: Linguistic features, biomarker profiles and brain metabolic patterns. J Neurol Sci 2024; 460:122998. [PMID: 38615405 DOI: 10.1016/j.jns.2024.122998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 04/02/2024] [Accepted: 04/04/2024] [Indexed: 04/16/2024]
Abstract
Mixed primary progressive aphasia (mPPA) accounts for a substantial proportion of primary progressive aphasia (PPA) cases. However, the lack of a standardised definition of this condition has resulted in misclassification of PPA cases. In this study, we enrolled 55 patients diagnosed with PPA, comprising 12 semantic variant (svPPA), 23 logopenic variant (lvPPA), and 20 mPPA cases with linguistic characteristics consistent with both svPPA and lvPPA (s/lvPPA). All patients underwent language assessments, evaluation of Alzheimer's disease biomarkers (via cerebrospinal fluid analysis or Amyloid-PET), and 18F-FDG-PET brain scans. An agglomerative hierarchical clustering (AHC) analysis based on linguistic characteristics revealed two distinct clusters within the s/lvPPA group: cluster k1 (n = 10) displayed an AD-like biomarker profile, with lower levels of Aβ42 and Aβ42/Aβ40 ratio, along with higher levels of t-tau and p-tau compared to cluster k2 (n = 10). Interestingly, k1 exhibited linguistic features that were similar to those of svPPA. Both clusters exhibited extensive temporoparietal hypometabolism. These findings support the hypothesis that a subgroup of s/lvPPA may represent a clinical manifestation of AD-related PPA.
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Affiliation(s)
- Salvatore Mazzeo
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Italy; Research and Innovation Centre for Dementia-CRIDEM, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy; Vita-Salute San Raffaele University, Milan, Italy; IRCCS Policlinico San Donato, San Donato Milanese, Italy
| | - Carmen Morinelli
- Research and Innovation Centre for Dementia-CRIDEM, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy
| | | | - Giulia Giacomucci
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Italy
| | - Valentina Moschini
- Research and Innovation Centre for Dementia-CRIDEM, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy
| | - Assunta Ingannato
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Italy
| | - Juri Balestrini
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Italy
| | - Daniele Frigerio
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Italy
| | - Filippo Emiliani
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Italy
| | - Giulia Galdo
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Italy
| | - Chiara Crucitti
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Italy
| | - Diletta Piazzesi
- Research and Innovation Centre for Dementia-CRIDEM, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy
| | - Silvia Bagnoli
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Italy
| | - Sonia Padiglioni
- Research and Innovation Centre for Dementia-CRIDEM, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy; Regional Referral Centre for Relational Criticalities, 50139 Tuscany Region, Italy
| | - Valentina Berti
- Department of Biomedical, Experimental and Clinical Sciences "Mario Serio", University of Florence, Italy
| | - Sandro Sorbi
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Italy; IRCCS Fondazione Don Carlo Gnocchi, Florence, Italy
| | - Benedetta Nacmias
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Italy; IRCCS Fondazione Don Carlo Gnocchi, Florence, Italy
| | - Valentina Bessi
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Italy; Research and Innovation Centre for Dementia-CRIDEM, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy.
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Jebahi F, Kielar A. The relationship between semantics, phonology, and naming performance in aphasia: a structural equation modeling approach. Cogn Neuropsychol 2024; 41:113-128. [PMID: 38970815 DOI: 10.1080/02643294.2024.2373842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 06/20/2024] [Accepted: 06/24/2024] [Indexed: 07/08/2024]
Abstract
The exploration of naming error patterns in aphasia provides insights into the cognitive processes underlying naming performance. We investigated how semantic and phonological abilities correlate and how they influence naming performance in aphasia. Data from 296 individuals with aphasia, drawn from the Moss Aphasia Psycholinguistics Project Database, were analyzed using a structural equation model. The model incorporated latent variables for semantics and phonology and manifest variables for naming accuracy and error patterns. There was a moderate positive correlation between semantics and phonology after controlling for overall aphasia severity. Both semantic and phonological abilities influenced naming accuracy. Semantic abilities negatively related to semantic, mixed, unrelated errors, and no responses. Interestingly, phonology positively affected semantic errors. Additionally, phonological abilities negatively related to each of phonological and neologism errors. These results highlight the role of semantic and phonological skills on naming performance in aphasia and reveal a relationship between these cognitive processes.
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Affiliation(s)
- Fatima Jebahi
- Department of Speech, Language and Hearing Sciences, University of Arizona, Tucson, AZ, USA
- Cognitive Science Graduate Interdisciplinary Program, University of Arizona, Tucson, AZ, USA
| | - Aneta Kielar
- Department of Speech, Language and Hearing Sciences, University of Arizona, Tucson, AZ, USA
- Cognitive Science Graduate Interdisciplinary Program, University of Arizona, Tucson, AZ, USA
- BIO5 Institute, University of Arizona, Tucson, AZ, USA
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11
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Harrington RM, Kristinsson S, Wilmskoetter J, Busby N, den Ouden D, Rorden C, Fridriksson J, Bonilha L. Dissociating reading and auditory comprehension in persons with aphasia. Brain Commun 2024; 6:fcae102. [PMID: 38585671 PMCID: PMC10998352 DOI: 10.1093/braincomms/fcae102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 01/10/2024] [Accepted: 03/21/2024] [Indexed: 04/09/2024] Open
Abstract
Language comprehension is often affected in individuals with post-stroke aphasia. However, deficits in auditory comprehension are not fully correlated with deficits in reading comprehension and the mechanisms underlying this dissociation remain unclear. This distinction is important for understanding language mechanisms, predicting long-term impairments and future development of treatment interventions. Using comprehensive auditory and reading measures from a large cohort of individuals with aphasia, we evaluated the relationship between aphasia type and reading comprehension impairments, the relationship between auditory versus reading comprehension deficits and the crucial neuroanatomy supporting the dissociation between post-stroke reading and auditory deficits. Scores from the Western Aphasia Battery-Revised from 70 participants with aphasia after a left-hemisphere stroke were utilized to evaluate both reading and auditory comprehension of linguistically equivalent stimuli. Repeated-measures and univariate ANOVA were used to assess the relationship between auditory comprehension and aphasia types and correlations were employed to test the relationship between reading and auditory comprehension deficits. Lesion-symptom mapping was used to determine the dissociation of crucial brain structures supporting reading comprehension deficits controlling for auditory deficits and vice versa. Participants with Broca's or global aphasia had the worst performance on reading comprehension. Auditory comprehension explained 26% of the variance in reading comprehension for sentence completion and 44% for following sequential commands. Controlling for auditory comprehension, worse reading comprehension performance was independently associated with damage to the inferior temporal gyrus, fusiform gyrus, posterior inferior temporal gyrus, inferior occipital gyrus, lingual gyrus and posterior thalamic radiation. Auditory and reading comprehension are only partly correlated in aphasia. Reading is an integral part of daily life and directly associated with quality of life and functional outcomes. This study demonstrated that reading performance is directly related to lesioned areas in the boundaries between visual association regions and ventral stream language areas. This behavioural and neuroanatomical dissociation provides information about the neurobiology of language and mechanisms for potential future treatment interventions.
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Affiliation(s)
- Rachael M Harrington
- Department of Communication Sciences and Disorders and Center for Research on the Challenges of Acquiring Language and Literacy, Georgia State University, Atlanta, GA 30310, USA
| | - Sigfus Kristinsson
- Department of Communication Sciences and Disorders, University of South Carolina, Columbia, SC 29208, USA
| | - Janina Wilmskoetter
- Department of Health and Rehabilitation Sciences, Medical University of South Carolina, Charleston, SC 29464, USA
| | - Natalie Busby
- Department of Communication Sciences and Disorders, University of South Carolina, Columbia, SC 29208, USA
| | - Dirk den Ouden
- Department of Communication Sciences and Disorders, University of South Carolina, Columbia, SC 29208, USA
| | - Chris Rorden
- Department of Psychology, University of South Carolina, Columbia, SC 29208, USA
| | - Julius Fridriksson
- Department of Communication Sciences and Disorders, University of South Carolina, Columbia, SC 29208, USA
| | - Leonardo Bonilha
- School of Medicine Columbia, University of South Carolina, Columbia, SC 29208, USA
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12
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Santi GC, Conca F, Esposito V, Polito C, Caminiti SP, Boccalini C, Morinelli C, Berti V, Mazzeo S, Bessi V, Marcone A, Iannaccone S, Kim SK, Sorbi S, Perani D, Cappa SF, Catricalà E. 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. Alzheimers Res Ther 2024; 16:49. [PMID: 38448894 PMCID: PMC10918940 DOI: 10.1186/s13195-024-01403-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 01/29/2024] [Indexed: 03/08/2024]
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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Affiliation(s)
- Gaia Chiara Santi
- IUSS Cognitive Neuroscience (ICoN) Center, Scuola Universitaria Superiore IUSS, Pavia, Italy
| | | | | | | | | | | | - Carmen Morinelli
- Research and Innovation Centre for Dementia-CRIDEM, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy
| | - Valentina Berti
- Department of Biomedical Experimental and Clinical Sciences, University of Florence, Florence, Italy
| | - Salvatore Mazzeo
- Research and Innovation Centre for Dementia-CRIDEM, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy
| | - Valentina Bessi
- Research and Innovation Centre for Dementia-CRIDEM, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy
| | - Alessandra Marcone
- Department of Rehabilitation and Functional Recovery, San Raffaele Hospital, Milan, Italy
| | - Sandro Iannaccone
- Department of Rehabilitation and Functional Recovery, San Raffaele Hospital, Milan, Italy
| | - Se-Kang Kim
- Department of Paediatrics, Baylor College of Medicine, Houston, TX, USA
| | - Sandro Sorbi
- IRCCS Fondazione Don Carlo Gnocchi, Florence, Italy
- Research and Innovation Centre for Dementia-CRIDEM, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy
| | - Daniela Perani
- Vita-Salute San Raffaele University, Milan, Italy
- Nuclear Medicine Unit, San Raffaele Hospital, Milan, Italy
| | - Stefano F Cappa
- IUSS Cognitive Neuroscience (ICoN) Center, Scuola Universitaria Superiore IUSS, Pavia, Italy.
- IRCCS Mondino Foundation, Pavia, Italy, Pavia, Italy.
| | - Eleonora Catricalà
- IUSS Cognitive Neuroscience (ICoN) Center, Scuola Universitaria Superiore IUSS, Pavia, Italy
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Kram L, Ohlerth AK, Ille S, Meyer B, Krieg SM. CompreTAP: Feasibility and reliability of a new language comprehension mapping task via preoperative navigated transcranial magnetic stimulation. Cortex 2024; 171:347-369. [PMID: 38086145 DOI: 10.1016/j.cortex.2023.09.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 02/01/2023] [Accepted: 09/25/2023] [Indexed: 02/12/2024]
Abstract
OBJECTIVE Stimulation-based language mapping approaches that are used pre- and intraoperatively employ predominantly overt language tasks requiring sufficient language production abilities. Yet, these production-based setups are often not feasible in brain tumor patients with severe expressive aphasia. This pilot study evaluated the feasibility and reliability of a newly developed language comprehension task with preoperative navigated transcranial magnetic stimulation (nTMS). METHODS Fifteen healthy subjects and six brain tumor patients with severe expressive aphasia unable to perform classic overt naming tasks underwent preoperative nTMS language mapping based on an auditory single-word Comprehension TAsk for Perioperative mapping (CompreTAP). Comprehension was probed by button-press responses to auditory stimuli, hence not requiring overt language responses. Positive comprehension areas were identified when stimulation elicited an incorrect or delayed button press. Error categories, case-wise cortical error rate distribution and inter-rater reliability between two experienced specialists were examined. RESULTS Overall, the new setup showed to be feasible. Comprehension-disruptions induced by nTMS manifested in no responses, delayed or hesitant responses, searching behavior or selection of wrong target items across all patients and controls and could be performed even in patients with severe expressive aphasia. The analysis agreement between both specialists was substantial for classifying comprehension-positive and -negative sites. Extensive left-hemispheric individual cortical comprehension sites were identified for all patients. Apart from one case presenting with transient worsening of aphasic symptoms, pre-existing language deficits did not aggravate if results were used for subsequent surgical planning. CONCLUSION Employing this new comprehension-based nTMS setup allowed to identify language relevant cortical sites in all healthy subjects and severely aphasic patients who were thus far precluded from classic production-based mapping. This pilot study, moreover, provides first indications that the CompreTAP mapping results may support the preservation of residual language function if used for subsequent surgical planning.
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Affiliation(s)
- Leonie Kram
- Department of Neurosurgery, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Germany; Department of Neurosurgery, Heidelberg University Hospital, Ruprecht-Karls-University Heidelberg, Germany
| | - Ann-Katrin Ohlerth
- Department of Neurosurgery, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Germany; Neurobiology of Language Department, Max Planck Institute for Psycholinguistics, Nijmegen, the Netherlands
| | - Sebastian Ille
- Department of Neurosurgery, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Germany; TUM Neuroimaging Center, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Germany; Department of Neurosurgery, Heidelberg University Hospital, Ruprecht-Karls-University Heidelberg, Germany
| | - Bernhard Meyer
- Department of Neurosurgery, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Germany
| | - Sandro M Krieg
- Department of Neurosurgery, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Germany; TUM Neuroimaging Center, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Germany; Department of Neurosurgery, Heidelberg University Hospital, Ruprecht-Karls-University Heidelberg, Germany.
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14
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Belder CRS, Marshall CR, Jiang J, Mazzeo S, Chokesuwattanaskul A, Rohrer JD, Volkmer A, Hardy CJD, Warren JD. Primary progressive aphasia: six questions in search of an answer. J Neurol 2024; 271:1028-1046. [PMID: 37906327 PMCID: PMC10827918 DOI: 10.1007/s00415-023-12030-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Accepted: 09/27/2023] [Indexed: 11/02/2023]
Abstract
Here, we review recent progress in the diagnosis and management of primary progressive aphasia-the language-led dementias. We pose six key unanswered questions that challenge current assumptions and highlight the unresolved difficulties that surround these diseases. How many syndromes of primary progressive aphasia are there-and is syndromic diagnosis even useful? Are these truly 'language-led' dementias? How can we diagnose (and track) primary progressive aphasia better? Can brain pathology be predicted in these diseases? What is their core pathophysiology? In addition, how can primary progressive aphasia best be treated? We propose that pathophysiological mechanisms linking proteinopathies to phenotypes may help resolve the clinical complexity of primary progressive aphasia, and may suggest novel diagnostic tools and markers and guide the deployment of effective therapies.
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Affiliation(s)
- Christopher R S Belder
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, 8 - 11 Queen Square, London, WC1N 3BG, UK
- UK Dementia Research Institute at UCL, UCL Queen Square Institute of Neurology, University College London, London, UK
- Adelaide Medical School, The University of Adelaide, Adelaide, South Australia, Australia
| | - Charles R Marshall
- Preventive Neurology Unit, Wolfson Institute of Population Health, Queen Mary University of London, London, UK
| | - Jessica Jiang
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, 8 - 11 Queen Square, London, WC1N 3BG, UK
| | - Salvatore Mazzeo
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, 8 - 11 Queen Square, London, WC1N 3BG, UK
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Azienda Ospedaliera-Universitaria Careggi, Florence, Italy
| | - Anthipa Chokesuwattanaskul
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, 8 - 11 Queen Square, London, WC1N 3BG, UK
- Division of Neurology, Department of Internal Medicine, King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand
- Cognitive Clinical and Computational Neuroscience Research Unit, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Jonathan D Rohrer
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, 8 - 11 Queen Square, London, WC1N 3BG, UK
| | - Anna Volkmer
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, 8 - 11 Queen Square, London, WC1N 3BG, UK
| | - Chris J D Hardy
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, 8 - 11 Queen Square, London, WC1N 3BG, UK
| | - Jason D Warren
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, 8 - 11 Queen Square, London, WC1N 3BG, UK.
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15
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Hardy CJD, Taylor‐Rubin C, Taylor B, Harding E, Gonzalez AS, Jiang J, Thompson L, Kingma R, Chokesuwattanaskul A, Walker F, Barker S, Brotherhood E, Waddington C, Wood O, Zimmermann N, Kupeli N, Yong KXX, Camic PM, Stott J, Marshall CR, Oxtoby NP, Rohrer JD, Volkmer A, Crutch SJ, Warren JD. Symptom-led staging for semantic and non-fluent/agrammatic variants of primary progressive aphasia. Alzheimers Dement 2024; 20:195-210. [PMID: 37548125 PMCID: PMC10917001 DOI: 10.1002/alz.13415] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 07/07/2023] [Accepted: 07/10/2023] [Indexed: 08/08/2023]
Abstract
INTRODUCTION Here we set out to create a symptom-led staging system for the canonical semantic and non-fluent/agrammatic variants of primary progressive aphasia (PPA), which present unique diagnostic and management challenges not well captured by functional scales developed for Alzheimer's disease and other dementias. METHODS An international PPA caregiver cohort was surveyed on symptom development under six provisional clinical stages and feedback was analyzed using a mixed-methods sequential explanatory design. RESULTS Both PPA syndromes were characterized by initial communication dysfunction and non-verbal behavioral changes, with increasing syndromic convergence and functional dependency at later stages. Milestone symptoms were distilled to create a prototypical progression and severity scale of functional impairment: the PPA Progression Planning Aid ("PPA-Squared"). DISCUSSION This work introduces a symptom-led staging scheme and functional scale for semantic and non-fluent/agrammatic variants of PPA. Our findings have implications for diagnostic and care pathway guidelines, trial design, and personalized prognosis and treatment for PPA. HIGHLIGHTS We introduce new symptom-led perspectives on primary progressive aphasia (PPA). The focus is on non-fluent/agrammatic (nfvPPA) and semantic (svPPA) variants. Foregrounding of early and non-verbal features of PPA and clinical trajectories is featured. We introduce a symptom-led staging scheme for PPA. We propose a prototype for a functional impairment scale, the PPA Progression Planning Aid.
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Affiliation(s)
- Chris J. D. Hardy
- Dementia Research CentreUCL Queen Square Institute of NeurologyUCLLondonUK
| | - Cathleen Taylor‐Rubin
- Uniting War Memorial HospitalSydneyAustralia
- Faculty of MedicineHealth and Human SciencesMacquarie UniversitySydneyAustralia
| | - Beatrice Taylor
- Centre for Medical Image ComputingDepartment of Computer ScienceUCLLondonUK
| | - Emma Harding
- Dementia Research CentreUCL Queen Square Institute of NeurologyUCLLondonUK
| | | | - Jessica Jiang
- Dementia Research CentreUCL Queen Square Institute of NeurologyUCLLondonUK
| | | | | | - Anthipa Chokesuwattanaskul
- Dementia Research CentreUCL Queen Square Institute of NeurologyUCLLondonUK
- Division of NeurologyDepartment of Internal MedicineKing Chulalongkorn Memorial HospitalBangkokThailand
- Cognitive Clinical and Computational Neuroscience Research UnitFaculty of MedicineChulalongkorn UniversityBangkokThailand
| | | | - Suzie Barker
- Dementia Research CentreUCL Queen Square Institute of NeurologyUCLLondonUK
| | - Emilie Brotherhood
- Dementia Research CentreUCL Queen Square Institute of NeurologyUCLLondonUK
| | - Claire Waddington
- Dementia Research CentreUCL Queen Square Institute of NeurologyUCLLondonUK
| | - Olivia Wood
- Dementia Research CentreUCL Queen Square Institute of NeurologyUCLLondonUK
| | - Nikki Zimmermann
- Dementia Research CentreUCL Queen Square Institute of NeurologyUCLLondonUK
| | - Nuriye Kupeli
- Marie Curie Palliative Care Research DepartmentDivision of PsychiatryUCLLondonUK
| | - Keir X. X. Yong
- Dementia Research CentreUCL Queen Square Institute of NeurologyUCLLondonUK
| | - Paul M. Camic
- Dementia Research CentreUCL Queen Square Institute of NeurologyUCLLondonUK
| | - Joshua Stott
- Dementia Research CentreUCL Queen Square Institute of NeurologyUCLLondonUK
- ADAPT LabResearch Department of ClinicalEducational and Health PsychologyUCLLondonUK
| | | | - Neil P. Oxtoby
- Centre for Medical Image ComputingDepartment of Computer ScienceUCLLondonUK
| | - Jonathan D. Rohrer
- Dementia Research CentreUCL Queen Square Institute of NeurologyUCLLondonUK
| | - Anna Volkmer
- Dementia Research CentreUCL Queen Square Institute of NeurologyUCLLondonUK
- Psychology and Language Sciences (PALS)UCLLondonUK
| | | | - Jason D. Warren
- Dementia Research CentreUCL Queen Square Institute of NeurologyUCLLondonUK
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Rezaii N, Quimby M, Wong B, Hochberg D, Brickhouse M, Touroutoglou A, Dickerson BC, Wolff P. Using Generative Artificial Intelligence to Classify Primary Progressive Aphasia from Connected Speech. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.12.22.23300470. [PMID: 38234853 PMCID: PMC10793520 DOI: 10.1101/2023.12.22.23300470] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Neurodegenerative dementia syndromes, such as Primary Progressive Aphasias (PPA), have traditionally been diagnosed based in part on verbal and nonverbal cognitive profiles. Debate continues about whether PPA is best subdivided into three variants and also regarding the most distinctive linguistic features for classifying PPA variants. In this study, we harnessed the capabilities of artificial intelligence (AI) and natural language processing (NLP) to first perform unsupervised classification of concise, connected speech samples from 78 PPA patients. Large Language Models discerned three distinct PPA clusters, with 88.5% agreement with independent clinical diagnoses. Patterns of cortical atrophy of three data-driven clusters corresponded to the localization in the clinical diagnostic criteria. We then used NLP to identify linguistic features that best dissociate the three PPA variants. Seventeen features emerged as most valuable for this purpose, including the observation that separating verbs into high and low-frequency types significantly improves classification accuracy. Using these linguistic features derived from the analysis of brief connected speech samples, we developed a classifier that achieved 97.9% accuracy in predicting PPA subtypes and healthy controls. Our findings provide pivotal insights for refining early-stage dementia diagnosis, deepening our understanding of the characteristics of these neurodegenerative phenotypes and the neurobiology of language processing, and enhancing diagnostic evaluation accuracy.
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Affiliation(s)
- Neguine Rezaii
- Frontotemporal Disorders Unit, Massachusetts General Hospital & Harvard Medical School, Boston MA, USA
- Department of Neurology, Massachusetts General Hospital & Harvard Medical School, Boston MA, USA
| | - Megan Quimby
- Frontotemporal Disorders Unit, Massachusetts General Hospital & Harvard Medical School, Boston MA, USA
| | - Bonnie Wong
- Frontotemporal Disorders Unit, Massachusetts General Hospital & Harvard Medical School, Boston MA, USA
- Department of Psychiatry, Massachusetts General Hospital & Harvard Medical School, Boston MA, USA
| | - Daisy Hochberg
- Frontotemporal Disorders Unit, Massachusetts General Hospital & Harvard Medical School, Boston MA, USA
| | - Michael Brickhouse
- Frontotemporal Disorders Unit, Massachusetts General Hospital & Harvard Medical School, Boston MA, USA
| | - Alexandra Touroutoglou
- Frontotemporal Disorders Unit, Massachusetts General Hospital & Harvard Medical School, Boston MA, USA
- Department of Neurology, Massachusetts General Hospital & Harvard Medical School, Boston MA, USA
- Massachusetts Alzheimer’s Disease Research Center, Massachusetts General Hospital & Harvard Medical School, Boston MA, USA
| | - Bradford C. Dickerson
- Frontotemporal Disorders Unit, Massachusetts General Hospital & Harvard Medical School, Boston MA, USA
- Department of Neurology, Massachusetts General Hospital & Harvard Medical School, Boston MA, USA
- Department of Psychiatry, Massachusetts General Hospital & Harvard Medical School, Boston MA, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital & Harvard Medical School, Boston MA, USA
- Massachusetts Alzheimer’s Disease Research Center, Massachusetts General Hospital & Harvard Medical School, Boston MA, USA
| | - Phillip Wolff
- Department of Psychology, Emory University, Atlanta, GA, USA
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17
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Ramanan S, Halai AD, Garcia-Penton L, Perry AG, Patel N, Peterson KA, Ingram RU, Storey I, Cappa SF, Catricala E, Patterson K, Rowe JB, Garrard P, Ralph MAL. The neural substrates of transdiagnostic cognitive-linguistic heterogeneity in primary progressive aphasia. Alzheimers Res Ther 2023; 15:219. [PMID: 38102724 PMCID: PMC10724982 DOI: 10.1186/s13195-023-01350-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 11/08/2023] [Indexed: 12/17/2023]
Abstract
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. The neurobiological basis of this cognitive-linguistic heterogeneity remains unclear. Understanding the relationship between these variables would improve PPA clinical/research characterisation and strengthen clinical trial and symptomatic treatment design. We address these knowledge gaps using a data-driven transdiagnostic approach to chart cognitive-linguistic differences and their associations with grey/white matter degeneration across multiple PPA variants. METHODS Forty-seven patients (13 semantic, 15 non-fluent, and 19 logopenic variant PPA) underwent assessment of general cognition, errors on language performance, and structural and diffusion magnetic resonance imaging to index whole-brain grey and white matter changes. Behavioural data were entered into varimax-rotated principal component analyses to derive orthogonal dimensions explaining the majority of cognitive variance. To uncover neural correlates of cognitive heterogeneity, derived components were used as covariates in neuroimaging analyses of grey matter (voxel-based morphometry) and white matter (network-based statistics of structural connectomes). RESULTS Four behavioural components emerged: general cognition, semantic memory, working memory, and motor speech/phonology. Performance patterns on the latter three principal components were in keeping with each variant's characteristic profile, but with a spectrum rather than categorical distribution across the cohort. General cognitive changes were most marked in logopenic variant PPA. Regardless of clinical diagnosis, general cognitive impairment was associated with inferior/posterior parietal grey/white matter involvement, semantic memory deficits with bilateral anterior temporal grey/white matter changes, working memory impairment with temporoparietal and frontostriatal grey/white matter involvement, and motor speech/phonology deficits with inferior/middle frontal grey matter alterations. CONCLUSIONS Cognitive-linguistic heterogeneity in PPA closely relates to individual-level variations on multiple behavioural dimensions and grey/white matter degeneration of regions within and beyond the language network. We further show that employment of transdiagnostic approaches may help to understand clinical symptom boundaries and reveal clinical and neural profiles that are shared across categorically defined variants of PPA.
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Affiliation(s)
- Siddharth Ramanan
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, 15 Chaucer Road, Cambridge, CB2 7EF, UK.
| | - Ajay D Halai
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, 15 Chaucer Road, Cambridge, CB2 7EF, UK
| | - Lorna Garcia-Penton
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, 15 Chaucer Road, Cambridge, CB2 7EF, UK
| | - Alistair G Perry
- Department of Clinical Neurosciences and Cambridge University Hospitals NHS Trust, University of Cambridge, Cambridge, UK
| | - Nikil Patel
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, UK
| | - Katie A Peterson
- Department of Clinical Neurosciences and Cambridge University Hospitals NHS Trust, University of Cambridge, Cambridge, UK
| | - Ruth U Ingram
- Division of Psychology and Mental Health, University of Manchester, Manchester, UK
| | - Ian Storey
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, UK
| | - Stefano F Cappa
- IUSS Cognitive Neuroscience Center (ICoN), University Institute of Advanced Studies IUSS, Pavia, Italy
- Dementia Research Center, IRCCS Mondino Foundation, Pavia, Italy
| | - Eleonora Catricala
- IUSS Cognitive Neuroscience Center (ICoN), University Institute of Advanced Studies IUSS, Pavia, Italy
- Dementia Research Center, IRCCS Mondino Foundation, Pavia, Italy
| | - Karalyn Patterson
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, 15 Chaucer Road, Cambridge, CB2 7EF, UK
| | - James B Rowe
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, 15 Chaucer Road, Cambridge, CB2 7EF, UK
- Department of Clinical Neurosciences and Cambridge University Hospitals NHS Trust, University of Cambridge, Cambridge, UK
| | - Peter Garrard
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, UK
| | - Matthew A Lambon Ralph
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, 15 Chaucer Road, Cambridge, CB2 7EF, UK
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18
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Pini L, Bisogno AL, Salvalaggio A, Shulman GL, Corbetta M. The correlation of behavioural deficits post-stroke: a trivial issue? Brain 2023; 146:e83-e85. [PMID: 37226212 DOI: 10.1093/brain/awad173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 05/06/2023] [Indexed: 05/26/2023] Open
Affiliation(s)
- Lorenzo Pini
- Padova Neuroscience Center, University of Padova, 35131 Padova, Italy
- Veneto Institute of Molecular Medicine, VIMM, 35129 Padova, Italy
| | | | - Alessandro Salvalaggio
- Padova Neuroscience Center, University of Padova, 35131 Padova, Italy
- Department of Neuroscience, University of Padova, 35131 Padova, Italy
| | - Gordon L Shulman
- Department of Neurology, Washington University in Saint Louis, St Louis, MO 63110, USA
- Department of Radiology, Washington University in Saint Louis, St Louis, MO 63110, USA
| | - Maurizio Corbetta
- Padova Neuroscience Center, University of Padova, 35131 Padova, Italy
- Veneto Institute of Molecular Medicine, VIMM, 35129 Padova, Italy
- Department of Neuroscience, University of Padova, 35131 Padova, Italy
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19
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Staiger A, Schroeter ML, Ziegler W, Pino D, Regenbrecht F, Schölderle T, Rieger T, Riedl L, Müller-Sarnowski F, Diehl-Schmid J. Speech Motor Profiles in Primary Progressive Aphasia. AMERICAN JOURNAL OF SPEECH-LANGUAGE PATHOLOGY 2023; 32:1296-1321. [PMID: 37099755 DOI: 10.1044/2023_ajslp-22-00319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
PURPOSE Previous research on motor speech disorders (MSDs) in primary progressive aphasia (PPA) has largely focused on patients with the nonfluent/agrammatic variant of PPA (nfvPPA), with few systematic descriptions of MSDs in variants other than nfvPPA. There has also been an emphasis on studying apraxia of speech, whereas less is known about dysarthria or other forms of MSDs. This study aimed to examine the qualitative and quantitative characteristics of MSDs in a prospective sample of individuals with PPA independent of subtype. METHOD We included 38 participants with a root diagnosis of PPA according to current consensus criteria, including one case with primary progressive apraxia of speech. Speech tasks comprised various speech modalities and levels of complexity. Expert raters used a novel protocol for auditory speech analyses covering all major dimensions of speech. RESULTS Of the participants, 47.4% presented with some form of MSD. Individual speech motor profiles varied widely with respect to the different speech dimensions. Besides apraxia of speech, we observed different dysarthria syndromes, special forms of MSDs (e.g., neurogenic stuttering), and mixed forms. Degrees of severity ranged from mild to severe. We also observed MSDs in patients whose speech and language profiles were incompatible with nfvPPA. CONCLUSIONS The results confirm that MSDs are common in PPA and can manifest in different syndromes. The findings emphasize that future studies of MSDs in PPA should be extended to all clinical variants and should take into account the qualitative characteristics of motor speech dysfunction across speech dimensions. SUPPLEMENTAL MATERIAL https://doi.org/10.23641/asha.22555534.
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Affiliation(s)
- Anja Staiger
- Clinical Neuropsychology Research Group (EKN), Institute of Phonetics and Speech Processing, Ludwig-Maximilians-Universität (LMU) München, Germany
| | - Matthias L Schroeter
- Max Planck Institute for Human Cognitive and Brain Sciences Leipzig & Clinic for Cognitive Neurology, University Hospital Leipzig, Germany
| | - Wolfram Ziegler
- Clinical Neuropsychology Research Group (EKN), Institute of Phonetics and Speech Processing, Ludwig-Maximilians-Universität (LMU) München, Germany
| | - Danièle Pino
- Max Planck Institute for Human Cognitive and Brain Sciences Leipzig & Clinic for Cognitive Neurology, University Hospital Leipzig, Germany
| | - Frank Regenbrecht
- Max Planck Institute for Human Cognitive and Brain Sciences Leipzig & Clinic for Cognitive Neurology, University Hospital Leipzig, Germany
| | - Theresa Schölderle
- Clinical Neuropsychology Research Group (EKN), Institute of Phonetics and Speech Processing, Ludwig-Maximilians-Universität (LMU) München, Germany
| | - Theresa Rieger
- Clinical Neuropsychology Research Group (EKN), Institute of Phonetics and Speech Processing, Ludwig-Maximilians-Universität (LMU) München, Germany
| | - Lina Riedl
- Department of Psychiatry and Psychotherapy, Technical University of Munich School of Medicine, Germany
| | - Felix Müller-Sarnowski
- Department of Psychiatry and Psychotherapy, Technical University of Munich School of Medicine, Germany
- Medical Information Sciences, Faculty of Medicine, University of Augsburg, Germany
| | - Janine Diehl-Schmid
- Department of Psychiatry and Psychotherapy, Technical University of Munich School of Medicine, Germany
- Munich Cluster for Systems Neurology (SyNergy), Germany
- kbo-Inn-Salzach-Klinikum, Clinical Center for Psychiatry, Psychotherapy, Psychosomatic Medicine, Geriatrics and Neurology, Wasserburg am Inn, Germany
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20
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Hardy CJD, Taylor-Rubin C, Taylor B, Harding E, Gonzalez AS, Jiang J, Thompson L, Kingma R, Chokesuwattanaskul A, Walker F, Barker S, Brotherhood E, Waddington C, Wood O, Zimmermann N, Kupeli N, Yong KXX, Camic PM, Stott J, Marshall CR, Oxtoby NP, Rohrer JD, Volkmer A, Crutch SJ, Warren JD. Symptom-led staging for primary progressive aphasia. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.03.13.23286972. [PMID: 36993460 PMCID: PMC10055437 DOI: 10.1101/2023.03.13.23286972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
The primary progressive aphasias (PPA) present complex and diverse challenges of diagnosis, management and prognosis. A clinically-informed, syndromic staging system for PPA would take a substantial step toward meeting these challenges. This study addressed this need using detailed, multi-domain mixed-methods symptom surveys of people with lived experience in a large international PPA cohort. We administered structured online surveys to caregivers of patients with a canonical PPA syndromic variant (nonfluent/agrammatic (nvPPA), semantic (svPPA) or logopenic (lvPPA)). In an 'exploratory' survey, a putative list and ordering of verbal communication and nonverbal functioning (nonverbal thinking, conduct and wellbeing, physical) symptoms was administered to 118 caregiver members of the UK national PPA Support Group. Based on feedback, we expanded the symptom list and created six provisional clinical stages for each PPA subtype. In a 'consolidation' survey, these stages were presented to 110 caregiver members of UK and Australian PPA Support Groups, and refined based on quantitative and qualitative feedback. Symptoms were retained if rated as 'present' by a majority (at least 50%) of respondents representing that PPA syndrome, and assigned to a consolidated stage based on majority consensus; the confidence of assignment was estimated for each symptom as the proportion of respondents in agreement with the final staging for that symptom. Qualitative responses were analysed using framework analysis. For each PPA syndrome, six stages ranging from 1 ('Very mild') to 6 ('Profound') were identified; earliest stages were distinguished by syndromic hallmark symptoms of communication dysfunction, with increasing trans-syndromic convergence and dependency for basic activities of daily living at later stages. Spelling errors, hearing changes and nonverbal behavioural features were reported at early stages in all syndromes. As the illness evolved, swallowing and mobility problems were reported earlier in nfvPPA than other syndromes, while difficulty recognising familiar people and household items characterised svPPA and visuospatial symptoms were more prominent in lvPPA. Overall confidence of symptom staging was higher for svPPA than other syndromes. Across syndromes, functional milestones were identified as key deficits that predict the sequence of major daily life impacts and associated management needs. Qualitatively, we identified five major themes encompassing 15 subthemes capturing respondents' experiences of PPA and suggestions for staging implementation. This work introduces a prototypical, symptom-led staging scheme for canonical PPA syndromes: the PPA Progression Planning Aid (PPA 2 ). Our findings have implications for diagnostic and care pathway guidelines, trial design and personalised prognosis and treatment for people living with these diseases.
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Affiliation(s)
- Chris JD Hardy
- Dementia Research Centre, UCL Queen Square Institute of Neurology, UCL, London, UK
| | - Cathleen Taylor-Rubin
- Uniting War Memorial Hospital, Sydney, Australia
- Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, Australia
| | - Beatrice Taylor
- Centre for Medical Image Computing, Department of Computer Science, UCL, London, UK
| | - Emma Harding
- Dementia Research Centre, UCL Queen Square Institute of Neurology, UCL, London, UK
| | - Aida Suarez Gonzalez
- Dementia Research Centre, UCL Queen Square Institute of Neurology, UCL, London, UK
| | - Jessica Jiang
- Dementia Research Centre, UCL Queen Square Institute of Neurology, UCL, London, UK
| | | | | | - Anthipa Chokesuwattanaskul
- Dementia Research Centre, UCL Queen Square Institute of Neurology, UCL, London, UK
- Division of Neurology, Department of Internal Medicine, King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand
- Cognitive Clinical and Computational Neuroscience Research Unit, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | | | - Suzie Barker
- Dementia Research Centre, UCL Queen Square Institute of Neurology, UCL, London, UK
| | - Emilie Brotherhood
- Dementia Research Centre, UCL Queen Square Institute of Neurology, UCL, London, UK
| | - Claire Waddington
- Dementia Research Centre, UCL Queen Square Institute of Neurology, UCL, London, UK
| | - Olivia Wood
- Dementia Research Centre, UCL Queen Square Institute of Neurology, UCL, London, UK
| | - Nikki Zimmermann
- Dementia Research Centre, UCL Queen Square Institute of Neurology, UCL, London, UK
| | - Nuriye Kupeli
- Marie Curie Palliative Care Research Department, Division of Psychiatry, UCL, London, UK
| | - Keir XX Yong
- Dementia Research Centre, UCL Queen Square Institute of Neurology, UCL, London, UK
| | - Paul M Camic
- Dementia Research Centre, UCL Queen Square Institute of Neurology, UCL, London, UK
| | - Josh Stott
- Dementia Research Centre, UCL Queen Square Institute of Neurology, UCL, London, UK
- ADAPTlab, Research Department of Clinical, Educational and Health Psychology, UCL, London, UK
| | | | - Neil P. Oxtoby
- Centre for Medical Image Computing, Department of Computer Science, UCL, London, UK
| | - Jonathan D Rohrer
- Dementia Research Centre, UCL Queen Square Institute of Neurology, UCL, London, UK
| | - Anna Volkmer
- Dementia Research Centre, UCL Queen Square Institute of Neurology, UCL, London, UK
- Psychology and Language Sciences (PALS), UCL, London, UK
| | - Sebastian J Crutch
- Dementia Research Centre, UCL Queen Square Institute of Neurology, UCL, London, UK
| | - Jason D Warren
- Dementia Research Centre, UCL Queen Square Institute of Neurology, UCL, London, UK
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21
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Ramanan S, El-Omar H, Roquet D, Ahmed RM, Hodges JR, Piguet O, Lambon Ralph MA, Irish M. Mapping behavioural, cognitive and affective transdiagnostic dimensions in frontotemporal dementia. Brain Commun 2023; 5:fcac344. [PMID: 36687395 PMCID: PMC9847565 DOI: 10.1093/braincomms/fcac344] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 09/26/2022] [Accepted: 01/03/2023] [Indexed: 01/09/2023] Open
Abstract
Two common clinical variants of frontotemporal dementia are the behavioural variant frontotemporal dementia, presenting with behavioural and personality changes attributable to prefrontal atrophy, and semantic dementia, displaying early semantic dysfunction primarily due to anterior temporal degeneration. Despite representing independent diagnostic entities, mounting evidence indicates overlapping cognitive-behavioural profiles in these syndromes, particularly with disease progression. Why such overlap occurs remains unclear. Understanding the nature of this overlap, however, is essential to improve early diagnosis, characterization and management of those affected. Here, we explored common cognitive-behavioural and neural mechanisms contributing to heterogeneous frontotemporal dementia presentations, irrespective of clinical diagnosis. This transdiagnostic approach allowed us to ascertain whether symptoms not currently considered core to these two syndromes are present in a significant proportion of cases and to explore the neural basis of clinical heterogeneity. Sixty-two frontotemporal dementia patients (31 behavioural variant frontotemporal dementia and 31 semantic dementia) underwent comprehensive neuropsychological, behavioural and structural neuroimaging assessments. Orthogonally rotated principal component analysis of neuropsychological and behavioural data uncovered eight statistically independent factors explaining the majority of cognitive-behavioural performance variation in behavioural variant frontotemporal dementia and semantic dementia. These factors included Behavioural changes, Semantic dysfunction, General Cognition, Executive function, Initiation, Disinhibition, Visuospatial function and Affective changes. Marked individual-level overlap between behavioural variant frontotemporal dementia and semantic dementia was evident on the Behavioural changes, General Cognition, Initiation, Disinhibition and Affective changes factors. Compared to behavioural variant frontotemporal dementia, semantic dementia patients displayed disproportionate impairment on the Semantic dysfunction factor, whereas greater impairment on Executive and Visuospatial function factors was noted in behavioural variant frontotemporal dementia. Both patient groups showed comparable magnitude of atrophy to frontal regions, whereas severe temporal lobe atrophy was characteristic of semantic dementia. Whole-brain voxel-based morphometry correlations with emergent factors revealed associations between fronto-insular and striatal grey matter changes with Behavioural, Executive and Initiation factor performance, bilateral temporal atrophy with Semantic dysfunction factor scores, parietal-subcortical regions with General Cognitive performance and ventral temporal atrophy associated with Visuospatial factor scores. Together, these findings indicate that cognitive-behavioural overlap (i) occurs systematically in frontotemporal dementia; (ii) varies in a graded manner between individuals and (iii) is associated with degeneration of different neural systems. Our findings suggest that phenotypic heterogeneity in frontotemporal dementia syndromes can be captured along continuous, multidimensional spectra of cognitive-behavioural changes. This has implications for the diagnosis of both syndromes amidst overlapping features as well as the design of symptomatic treatments applicable to multiple syndromes.
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Affiliation(s)
- Siddharth Ramanan
- Medical Research Council Cognition and Brain Sciences Unit, The University of Cambridge, Cambridge CB3 1AU, UK
- Brain and Mind Centre, The University of Sydney, Sydney, NSW 2050, Australia
- School of Psychology, The University of Sydney, Sydney, NSW 2050, Australia
| | - Hashim El-Omar
- Brain and Mind Centre, The University of Sydney, Sydney, NSW 2050, Australia
| | - Daniel Roquet
- Brain and Mind Centre, The University of Sydney, Sydney, NSW 2050, Australia
- School of Psychology, The University of Sydney, Sydney, NSW 2050, Australia
| | - Rebekah M Ahmed
- Brain and Mind Centre, The University of Sydney, Sydney, NSW 2050, Australia
- Memory and Cognition Clinic, Department of Clinical Neurosciences, Royal Prince Alfred Hospital, Sydney, NSW 2050, Australia
| | - John R Hodges
- Brain and Mind Centre, The University of Sydney, Sydney, NSW 2050, Australia
- School of Psychology, The University of Sydney, Sydney, NSW 2050, Australia
- School of Medical Sciences, The University of Sydney, Sydney, NSW 2050, Australia
| | - Olivier Piguet
- Brain and Mind Centre, The University of Sydney, Sydney, NSW 2050, Australia
- School of Psychology, The University of Sydney, Sydney, NSW 2050, Australia
| | - Matthew A Lambon Ralph
- Medical Research Council Cognition and Brain Sciences Unit, The University of Cambridge, Cambridge CB3 1AU, UK
| | - Muireann Irish
- Brain and Mind Centre, The University of Sydney, Sydney, NSW 2050, Australia
- School of Psychology, The University of Sydney, Sydney, NSW 2050, Australia
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22
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Comprehensive qualitative characterization of linguistic performance profiles in primary progressive aphasia: a multivariate study with FDG-PET. Neurobiol Aging 2022; 120:137-148. [DOI: 10.1016/j.neurobiolaging.2022.09.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 08/17/2022] [Accepted: 09/02/2022] [Indexed: 12/22/2022]
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23
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Tao Y, Tsapkini K, Rapp B. Inter-hemispheric synchronicity and symmetry: The functional connectivity consequences of stroke and neurodegenerative disease. NEUROIMAGE: CLINICAL 2022; 36:103263. [PMID: 36451366 PMCID: PMC9668669 DOI: 10.1016/j.nicl.2022.103263] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 11/02/2022] [Accepted: 11/06/2022] [Indexed: 11/09/2022] Open
Abstract
Stroke and neurodegenerative diseases differ along several dimensions, including their temporal trajectories -abrupt onset versus slow disease progression. Despite these differences, they can give rise to very similar cognitive impairments, such as specific forms of aphasia. What has been scarcely investigated, however, is the extent to which the underlying functional neuroplastic consequences are similar or different for these diseases. Here, for the first time, we directly compare changes in the brain's functional network connectivity, measured with resting-state fMRI, in stroke and progressive neurological disease. Specifically, we examined two groups of individuals with chronic post-stroke aphasia or non-fluent primary progressive aphasia, matched for their behavioral profiles and distribution of left-hemisphere damage. Using previous proposals regarding the neural functional connectivity (FC) phenotype of stroke as a starting point, we compared the two diseases in terms of homotopic FC, intra-hemispheric FC changes and also the symmetry of the FC patterns between the two hemispheres. We found, first, that progressive disease showed significantly higher levels of homotopic connectivity than neurotypical controls and, further, that stroke showed the reverse pattern. For both groups these effects were found to be behaviorally relevant. In addition, within the directly impacted left hemisphere, FC changes for the two diseases were significantly correlated. In contrast, in the right hemisphere, the FC changes differed markedly between the two groups, with the progressive disease group exhibiting rather symmetrical FC changes across the hemispheres whereas the post-stroke group showed asymmetrical FC changes across the hemispheres. These findings constitute novel evidence that the functional connectivity consequences of stroke and neurodegenerative disease can be very different despite similar behavioral outcomes and damage foci. Specifically, stroke may lead to greater independence of hemispheric responses, while neurodegenerative disease may produce more symmetrical changes across the hemispheres and more synchronized activity between the two hemispheres.
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Affiliation(s)
- Yuan Tao
- Department of Cognitive Science, Johns Hopkins University, Baltimore, MD 21218, USA,Corresponding author.
| | - Kyrana Tsapkini
- Department of Cognitive Science, Johns Hopkins University, Baltimore, MD 21218, USA,Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD 21217, USA
| | - Brenda Rapp
- Department of Cognitive Science, Johns Hopkins University, Baltimore, MD 21218, USA,Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD 21218, USA,Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD 21218, USA
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24
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Beeson PM, Rising K, Sachs A, Rapcsak SZ. Common predictors of spoken and written language performance in aphasia, alexia, and agraphia. Front Hum Neurosci 2022; 16:1025468. [PMID: 36419644 PMCID: PMC9677348 DOI: 10.3389/fnhum.2022.1025468] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 09/28/2022] [Indexed: 09/01/2024] Open
Abstract
Language performance requires support from central cognitive/linguistic abilities as well as the more peripheral sensorimotor skills to plan and implement spoken and written communication. Both output modalities are vulnerable to impairment following damage to the language-dominant hemisphere, but much of the research to date has focused exclusively on spoken language. In this study we aimed to examine an integrated model of language processing that includes the common cognitive processes that support spoken and written language, as well as modality-specific skills. To do so, we evaluated spoken and written language performance from 87 individuals with acquired language impairment resulting from damage to left perisylvian cortical regions that collectively constitute the dorsal language pathway. Comprehensive behavioral assessment served to characterize the status of central and peripheral components of language processing in relation to neurotypical controls (n = 38). Performance data entered into principal components analyses (with or without control scores) consistently yielded a strong five-factor solution. In line with a primary systems framework, three central cognitive factors emerged: semantics, phonology, and orthography that were distinguished from peripheral processes supporting speech production and allographic skill for handwriting. The central phonology construct reflected performance on phonological awareness and manipulation tasks and showed the greatest deficit of all the derived factors. Importantly, this phonological construct was orthogonal to the speech production factor that reflected repetition of words/non-words. When entered into regression analyses, semantics and phonological skill were common predictors of language performance across spoken and written modalities. The speech production factor was also a strong, distinct predictor of spoken naming and oral reading, in contrast to allographic skills which only predicted written output. As expected, visual orthographic processing contributed more to written than spoken language tasks and reading/spelling performance was strongly reliant on phonological and semantic abilities. Despite the heterogeneity of this cohort regarding aphasia type and severity, the marked impairment of phonological skill was a unifying feature. These findings prompt greater attention to clinical assessment and potential treatment of underlying phonological skill in individuals with left perisylvian damage.
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Affiliation(s)
- Pélagie M. Beeson
- Department of Speech, Language, and Hearing Sciences, The University of Arizona, Tucson, AZ, United States
- Department of Neurology, The University of Arizona, Tucson, AZ, United States
| | - Kindle Rising
- Department of Speech, Language, and Hearing Sciences, The University of Arizona, Tucson, AZ, United States
| | - Alyssa Sachs
- Department of Speech, Language, and Hearing Sciences, The University of Arizona, Tucson, AZ, United States
| | - Steven Z. Rapcsak
- Department of Speech, Language, and Hearing Sciences, The University of Arizona, Tucson, AZ, United States
- Department of Neurology, The University of Arizona, Tucson, AZ, United States
- Banner Alzheimer’s Institute, Tucson, AZ, United States
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25
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Ramanan S, Irish M, Patterson K, Rowe JB, Gorno-Tempini ML, Lambon Ralph MA. Understanding the multidimensional cognitive deficits of logopenic variant primary progressive aphasia. Brain 2022; 145:2955-2966. [PMID: 35857482 PMCID: PMC9473356 DOI: 10.1093/brain/awac208] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 05/06/2022] [Accepted: 05/27/2022] [Indexed: 02/02/2023] Open
Abstract
The logopenic variant of primary progressive aphasia is characterized by early deficits in language production and phonological short-term memory, attributed to left-lateralized temporoparietal, inferior parietal and posterior temporal neurodegeneration. Despite patients primarily complaining of language difficulties, emerging evidence points to performance deficits in non-linguistic domains. Temporoparietal cortex, and functional brain networks anchored to this region, are implicated as putative neural substrates of non-linguistic cognitive deficits in logopenic variant primary progressive aphasia, suggesting that degeneration of a shared set of brain regions may result in co-occurring linguistic and non-linguistic dysfunction early in the disease course. Here, we provide a Review aimed at broadening the understanding of logopenic variant primary progressive aphasia beyond the lens of an exclusive language disorder. By considering behavioural and neuroimaging research on non-linguistic dysfunction in logopenic variant primary progressive aphasia, we propose that a significant portion of multidimensional cognitive features can be explained by degeneration of temporal/inferior parietal cortices and connected regions. Drawing on insights from normative cognitive neuroscience, we propose that these regions underpin a combination of domain-general and domain-selective cognitive processes, whose disruption results in multifaceted cognitive deficits including aphasia. This account explains the common emergence of linguistic and non-linguistic cognitive difficulties in logopenic variant primary progressive aphasia, and predicts phenotypic diversification associated with progression of pathology in posterior neocortex.
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Affiliation(s)
- Siddharth Ramanan
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK
| | - Muireann Irish
- The University of Sydney, Brain and Mind Centre and School of Psychology, Sydney, Australia
| | - Karalyn Patterson
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK
| | - James B Rowe
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK
- Department of Clinical Neurosciences, Cambridge University Centre for Frontotemporal Dementia, Cambridge, UK
- Cambridge University Hospitals NHS Trust, Cambridge, UK
| | | | - Matthew A Lambon Ralph
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK
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26
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Belder CRS, Chokesuwattanaskul A, Marshall CR, Hardy CJD, Rohrer JD, Warren JD. The problematic syndrome of right temporal lobe atrophy: Unweaving the phenotypic rainbow. Front Neurol 2022; 13:1082828. [PMID: 36698890 PMCID: PMC9868162 DOI: 10.3389/fneur.2022.1082828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 12/14/2022] [Indexed: 01/10/2023] Open
Affiliation(s)
- Christopher R S Belder
- Department of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square, London, United Kingdom.,Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia
| | - Anthipa Chokesuwattanaskul
- Division of Neurology, Department of Internal Medicine, King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand.,Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Charles R Marshall
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom.,Preventive Neurology Unit, Wolfson Institute of Population Health, Queen Mary University of London, London, United Kingdom
| | - Chris J D Hardy
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Jonathan D Rohrer
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Jason D Warren
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
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27
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Watanabe H, Hikida S, Ikeda M, Mori E. OUP accepted manuscript. Brain Commun 2022; 4:fcac015. [PMID: 35686225 PMCID: PMC9171501 DOI: 10.1093/braincomms/fcac015] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 09/07/2021] [Accepted: 01/31/2022] [Indexed: 11/26/2022] Open
Abstract
Primary progressive aphasia, a neurodegenerative syndrome, presents mainly with language impairment. Both semantic and logopenic variants are fluent variants of primary progressive aphasia. Before the research criteria of primary progressive aphasia were proposed, progressive fluent aphasias, such as progressive anomic aphasia, transcortical sensory aphasia and Wernicke’s aphasia, were reported as classical progressive fluent aphasias seen in Alzheimer’s disease. However, since the research criteria of primary progressive aphasia were established, classical fluent variants (other than semantic and logopenic variants) have been neglected and have not been included in the current classification of primary progressive aphasia. This study aimed to determine whether unclassified fluent variants (other than semantic and logopenic variants) can be manifestations of primary progressive aphasia. This study also reconfirmed the characteristics of classical progressive fluent aphasia, such as progressive anomic aphasia, progressive transcortical sensory aphasia and progressive Wernicke’s aphasia as unclassified fluent variants of primary progressive aphasia, using comparison with the current model of primary progressive aphasia. Twelve consecutive patients with an unclassified fluent variant other than semantic or logopenic variant underwent language, neurological, neuropsychological and neuroimaging (MRI and single-photon emission computed tomography) testing. Based on comprehensive language tests, we redefined the diagnoses as primary progressive anomic aphasia (n = 8), primary progressive transcortical sensory aphasia (n = 3) and primary progressive Wernicke’s aphasia (n = 1). Anomic aphasia was characterized by anomia but preserved repetition and comprehension; transcortical sensory aphasia by relatively preserved repetition but poor word comprehension; and Wernicke’s aphasia by poor repetition and word comprehension. In patients with anomic aphasia, voxel-based morphometry of MRI data revealed cortical atrophy, which was most prominent in the temporoparietal lobes, with no obvious lateralization; in two-thirds of patients with transcortical sensory aphasia and in one patient with Wernicke’s aphasia, it revealed atrophy, predominantly in the left temporoparietal lobe. Statistical analysis of single-photon emission computed tomography using three-dimensional stereotactic surface projections revealed patterns of left-sided hypoperfusion in the majority of patients. The temporal and parietal lobes were involved in all cases; the degree of hypoperfusion was higher in patients with transcortical sensory aphasia or Wernicke’s aphasia than in patients with anomic aphasia. The present study demonstrated the clinical and imaging features of 12 patients with an unclassified fluent variant of primary progressive aphasia, which we redefined as primary progressive anomic aphasia, primary progressive transcortical sensory aphasia and primary progressive Wernicke’s aphasia. Classical fluent variants other than semantic and logopenic variants can be found in primary progressive aphasia.
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Affiliation(s)
- Hiroyuki Watanabe
- Correspondence to: Hiroyuki Watanabe Department of Behavioral Neurology and Neuropsychiatry Osaka University United Graduate School of Child Development 2-2, Yamadaoka, Suita Osaka 565-0871, Japan E-mail:
| | - Sakura Hikida
- Department of Psychiatry, Osaka University Graduate School of Medicine, Suita, Japan
- Brain Function Center, Nippon Life Hospital, Osaka, Japan
| | - Manabu Ikeda
- Department of Psychiatry, Osaka University Graduate School of Medicine, Suita, Japan
- Brain Function Center, Nippon Life Hospital, Osaka, Japan
| | - Etsuro Mori
- Department of Behavioral Neurology and Neuropsychiatry, Osaka University United Graduate School of Child Development, Suita, Japan
- Brain Function Center, Nippon Life Hospital, Osaka, Japan
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28
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Borghesani V, DeLeon J, Gorno-Tempini ML. Frontotemporal dementia: A unique window on the functional role of the temporal lobes. HANDBOOK OF CLINICAL NEUROLOGY 2022; 187:429-448. [PMID: 35964986 PMCID: PMC9793689 DOI: 10.1016/b978-0-12-823493-8.00011-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Frontotemporal dementia (FTD) is an umbrella term covering a plethora of progressive changes in executive functions, motor abilities, behavior, and/or language. Different clinical syndromes have been described in relation to localized atrophy, informing on the functional networks that underlie these specific cognitive, emotional, and behavioral processes. These functional declines are linked with the underlying neurodegeneration of frontal and/or temporal lobes due to diverse molecular pathologies. Initially, the accumulation of misfolded proteins targets specifically susceptible cell assemblies, leading to relatively focal neurodegeneration that later spreads throughout large-scale cortical networks. Here, we discuss the most recent clinical, neuropathological, imaging, and genetics findings in FTD-spectrum syndromes affecting the temporal lobe. We focus on the semantic variant of primary progressive aphasia and its mirror image, the right temporal variant of FTD. Incipient focal atrophy of the left anterior temporal lobe (ATL) manifests with predominant naming, word comprehension, reading, and object semantic deficits, while cases of predominantly right ATL atrophy present with impairments of socioemotional, nonverbal semantic, and person-specific knowledge. Overall, the observations in FTD allow for crucial clinical-anatomic inferences, shedding light on the role of the temporal lobes in both cognition and complex behaviors. The concerted activity of both ATLs is critical to ensure that percepts are translated into concepts, yet important hemispheric differences should be acknowledged. On one hand, the left ATL attributes meaning to linguistic, external stimuli, thus supporting goal-oriented, action-related behaviors (e.g., integrating sounds and letters into words). On the other hand, the right ATL assigns meaning to emotional, visceral stimuli, thus guiding socially relevant behaviors (e.g., integrating body sensations into feelings of familiarity).
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Affiliation(s)
- Valentina Borghesani
- Centre de recherche de l'Institut universitaire de gériatrie de Montréal, Montréal, QC, Canada; Department of Psychology, Université de Montréal, Montréal, QC, Canada.
| | - Jessica DeLeon
- Memory and Aging Center, Department of Neurology, University of California, San Francisco, CA, United States; Department of Neurology, Dyslexia Center, University of California, San Francisco, CA, United States
| | - Maria Luisa Gorno-Tempini
- Memory and Aging Center, Department of Neurology, University of California, San Francisco, CA, United States; Department of Neurology, Dyslexia Center, University of California, San Francisco, CA, United States
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29
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Patel N, Peterson KA, Ingram RU, Storey I, Cappa SF, Catricala E, Halai A, Patterson KE, Lambon Ralph MA, Rowe JB, Garrard P. A 'Mini Linguistic State Examination' to classify primary progressive aphasia. Brain Commun 2021; 4:fcab299. [PMID: 35282164 PMCID: PMC8914496 DOI: 10.1093/braincomms/fcab299] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 09/27/2021] [Accepted: 12/17/2021] [Indexed: 11/13/2022] Open
Abstract
There are few available methods for qualitatively evaluating patients with primary progressive aphasia. Commonly adopted approaches are time-consuming, of limited accuracy or designed to assess different patient populations. This paper introduces a new clinical test-the Mini Linguistic State Examination-which was designed uniquely to enable a clinician to assess and subclassify both classical and mixed presentations of primary progressive aphasia. The adoption of a novel assessment method (error classification) greatly amplifies the clinical information that can be derived from a set of standard linguistic tasks and allows a five-dimensional profile to be defined. Fifty-four patients and 30 matched controls were recruited. Five domains of language competence (motor speech, phonology, semantics, syntax and working memory) were assessed using a sequence of 11 distinct linguistic assays. A random forest classification was used to assess the diagnostic accuracy for predicting primary progressive aphasia subtypes and create a decision tree as a guide to clinical classification. The random forest prediction model was 96% accurate overall (92% for the logopenic variant, 93% for the semantic variant and 98% for the non-fluent variant). The derived decision tree produced a correct classification of 91% of participants whose data were not included in the training set. The Mini Linguistic State Examination is a new cognitive test incorporating a novel and powerful, yet straightforward, approach to scoring. Rigorous assessment of its diagnostic accuracy confirmed excellent matching of primary progressive aphasia syndromes to clinical gold standard diagnoses. Adoption of the Mini Linguistic State Examination by clinicians will have a decisive impact on the consistency and uniformity with which patients can be described clinically. It will also facilitate screening for cohort-based research, including future therapeutic trials, and is suitable for describing, quantifying and monitoring language deficits in other brain disorders.
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Affiliation(s)
- Nikil Patel
- Molecular and Clinical Sciences Research Institute, St George’s, University of London, London SW17 0RE, UK
| | - Katie A. Peterson
- Department of Clinical Neurosciences and Cambridge University Hospitals NHS Trust, University of Cambridge, Cambridge CB2 0SP, UK
| | - Ruth U. Ingram
- Division of Neuroscience and Experimental Psychology, University of Manchester, Manchester M13 9PL, UK
| | - Ian Storey
- Molecular and Clinical Sciences Research Institute, St George’s, University of London, London SW17 0RE, UK
| | - Stefano F. Cappa
- University Institute for Advanced Studies IUSS, Pavia, Italy
- IRCCS Mondino Foundation, Pavia, Italy
| | | | - Ajay Halai
- Department of Clinical Neurosciences and Cambridge University Hospitals NHS Trust, University of Cambridge, Cambridge CB2 0SP, UK
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
| | - Karalyn E. Patterson
- Department of Clinical Neurosciences and Cambridge University Hospitals NHS Trust, University of Cambridge, Cambridge CB2 0SP, UK
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
| | | | - James B. Rowe
- Department of Clinical Neurosciences and Cambridge University Hospitals NHS Trust, University of Cambridge, Cambridge CB2 0SP, UK
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
| | - Peter Garrard
- Molecular and Clinical Sciences Research Institute, St George’s, University of London, London SW17 0RE, UK
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30
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Gleichgerrcht E, Roth R, Fridriksson J, den Ouden D, Delgaizo J, Stark B, Hickok G, Rorden C, Wilmskoetter J, Hillis A, Bonilha L. Neural bases of elements of syntax during speech production in patients with aphasia. BRAIN AND LANGUAGE 2021; 222:105025. [PMID: 34555689 PMCID: PMC8546356 DOI: 10.1016/j.bandl.2021.105025] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 09/08/2021] [Accepted: 09/08/2021] [Indexed: 06/13/2023]
Abstract
The ability to string together words into a structured arrangement capable of conveying nuanced information is key to speech production. The assessment of the neural bases for structuring sentences has been challenged by the need of experts to delineate the aberrant morphosyntactic structures in aphasic speech. Most studies have relied on focused tasks with limited ecological validity. We characterized syntactic complexity during connected speech produced by patients with chronic post-stroke aphasia. We automated this process by employing Natural Language Processing (NLP). We conducted voxel-based and connectome-based lesion-symptom mapping to identify brain regions crucially associated with sentence production and syntactic complexity. Posterior-inferior aspects of left frontal and parietal lobes, as well as white matter tracts connecting these areas, were essential for syntactic complexity, particularly the posterior inferior frontal gyrus. These findings suggest that sentence structuring during word production depends on the integrity of Broca's area and the dorsal stream of language processing.
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Affiliation(s)
| | - Rebecca Roth
- Department of Neurology, Medical University of South Carolina, Charleston, SC, USA
| | - Julius Fridriksson
- Department of Communication Sciences and Disorders, University of South Carolina, Columbia, SC, USA
| | - Dirk den Ouden
- Department of Communication Sciences and Disorders, University of South Carolina, Columbia, SC, USA
| | - John Delgaizo
- Department of Neurology, Medical University of South Carolina, Charleston, SC, USA
| | - Brielle Stark
- Department of Speech and Hearing Sciences, Indiana University, Bloomington, IN, USA
| | - Gregory Hickok
- Department of Cognitive Sciences, University of California, Irvine, CA, USA
| | - Chris Rorden
- Department of Psychology, University of South Carolina, Columbia, SC, USA
| | - Janina Wilmskoetter
- Department of Neurology, Medical University of South Carolina, Charleston, SC, USA
| | - Argye Hillis
- Department of Neurology, Johns Hopkins University, Baltimore, MD, USA
| | - Leonardo Bonilha
- Department of Neurology, Medical University of South Carolina, Charleston, SC, USA.
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31
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Mesulam MM, Coventry CA, Rader BM, Kuang A, Sridhar J, Martersteck A, Zhang H, Thompson CK, Weintraub S, Rogalski EJ. Modularity and granularity across the language network-A primary progressive aphasia perspective. Cortex 2021; 141:482-496. [PMID: 34153680 PMCID: PMC8319115 DOI: 10.1016/j.cortex.2021.05.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 03/22/2021] [Accepted: 05/05/2021] [Indexed: 11/16/2022]
Abstract
Tests of grammar, repetition and semantics were administered to 62 prospectively enrolled right-handed participants with primary progressive aphasia (PPA). Structural brain images were obtained at the time of testing. Regression analyses uncovered 3 clearly delineated non-overlapping left hemisphere clusters where cortical thinning (atrophy) was significantly correlated with impaired performance. A morphosyntactic cluster associated with the grammaticality of sentence construction was located predominantly within the middle and inferior frontal gyri; a phonolexical cluster associated with language repetition was located in the temporoparietal junction; a lexicosemantic cluster associated with object naming and single word comprehension was located within the middle and anterior parts of the temporal lobe and extended into insular, orbitofrontal, and mediotemporal cortices. Commonality analyses were undertaken to explore whether these three clusters were as modular as indicated by the regression analyses or whether some underlying functional granularity could be uncovered. Modularity was defined as the exclusive association of an anatomical cluster with a single type of language task whereas granularity was defined as the association of a single anatomical cluster with more than one type of language task. The commonality analyses revealed a predominantly modular organization with quantitatively minor instances of inter-cluster granularity. The results also reconfirmed previous work on PPA which had shown that Wernicke's area is not essential for word comprehension, that naming impairments can be based either on deficits of lexical retrieval or word comprehension, and that the essential substrates of word comprehension encompass much wider areas of the temporal lobe than the temporal pole. The anatomy of the language network has traditionally been explored through patients with focal cerebrovascular accidents and experiments based on functional activation. Investigations on PPA are showing that focal neurodegenerations can add new perspectives to existing models of the language network.
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Affiliation(s)
- M-Marsel Mesulam
- Mesulam Center for Cognitive Neurology and Alzheimer's Disease, Northwestern University Feinberg School of Medicine, Chicago, IL, USA; Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
| | - Christina A Coventry
- Mesulam Center for Cognitive Neurology and Alzheimer's Disease, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | | | - Alan Kuang
- Northwestern University Feinberg School of Medicine, Department of Preventive Medicine, Chicago, IL, USA
| | - Jaiashre Sridhar
- Mesulam Center for Cognitive Neurology and Alzheimer's Disease, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Adam Martersteck
- Helen Wills Neuroscience Institute, University of California, Berkeley, CA, USA
| | - Hui Zhang
- Mesulam Center for Cognitive Neurology and Alzheimer's Disease, Northwestern University Feinberg School of Medicine, Chicago, IL, USA; Northwestern University Feinberg School of Medicine, Department of Preventive Medicine, Chicago, IL, USA
| | - Cynthia K Thompson
- Mesulam Center for Cognitive Neurology and Alzheimer's Disease, Northwestern University Feinberg School of Medicine, Chicago, IL, USA; Northwestern University School of Communication, Evanston, IL, USA
| | - Sandra Weintraub
- Mesulam Center for Cognitive Neurology and Alzheimer's Disease, Northwestern University Feinberg School of Medicine, Chicago, IL, USA; Northwestern University Feinberg School of Medicine, Department of Psychiatry and Behavioral Sciences, Chicago, IL, USA
| | - Emily J Rogalski
- Mesulam Center for Cognitive Neurology and Alzheimer's Disease, Northwestern University Feinberg School of Medicine, Chicago, IL, USA; Northwestern University Feinberg School of Medicine, Department of Psychiatry and Behavioral Sciences, Chicago, IL, USA
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32
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Landrigan JF, Zhang F, Mirman D. A data-driven approach to post-stroke aphasia classification and lesion-based prediction. Brain 2021; 144:1372-1383. [PMID: 34046670 PMCID: PMC8219353 DOI: 10.1093/brain/awab010] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 10/21/2020] [Accepted: 11/01/2020] [Indexed: 12/15/2022] Open
Abstract
Aphasia is an acquired impairment in the production or comprehension of language, typically caused by left hemisphere stroke. The subtyping framework used in clinical aphasiology today is based on the Wernicke-Lichtheim model of aphasia formulated in the late 19th century, which emphasizes the distinction between language production and comprehension. The current study used a data-driven approach that combined modern statistical, machine learning, and neuroimaging tools to examine behavioural deficit profiles and their lesion correlates and predictors in a large cohort of individuals with post-stroke aphasia. First, individuals with aphasia were clustered based on their behavioural deficit profiles using community detection analysis (CDA) and these clusters were compared with the traditional aphasia subtypes. Random forest classifiers were built to evaluate how well individual lesion profiles predict cluster membership. The results of the CDA analyses did not align with the traditional model of aphasia in either behavioural or neuroanatomical patterns. Instead, the results suggested that the primary distinction in aphasia (after severity) is between phonological and semantic processing rather than between production and comprehension. Further, lesion-based classification reached 75% accuracy for the CDA-based categories and only 60% for categories based on the traditional fluent/non-fluent aphasia distinction. The results of this study provide a data-driven basis for a new approach to classification of post-stroke aphasia subtypes in both research and clinical settings.
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Affiliation(s)
| | - Fengqing Zhang
- Department of Psychology, Drexel University, Philadelphia, PA 19104 USA
| | - Daniel Mirman
- Department of Psychology, University of Edinburgh, Edinburgh EH8 9JZ, UK
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33
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Rice GE, Kerry SJ, Robotham RJ, Leff AP, Lambon Ralph MA, Starrfelt R. Category-selective deficits are the exception and not the rule: Evidence from a case-series of 64 patients with ventral occipito-temporal cortex damage. Cortex 2021; 138:266-281. [PMID: 33770511 PMCID: PMC8064027 DOI: 10.1016/j.cortex.2021.01.021] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 11/30/2020] [Accepted: 01/22/2021] [Indexed: 02/07/2023]
Abstract
The organisational principles of the visual ventral stream are still highly debated, particularly the relative association/dissociation between word and face recognition and the degree of lateralisation of the underlying processes. Reports of dissociations between word and face recognition stem from single case-studies of category selective impairments, and neuroimaging investigations of healthy participants. Despite the historical reliance on single case-studies, more recent group studies have highlighted a greater commonality between word and face recognition. Studying individual patients with rare selective deficits misses (a) important variability between patients, (b) systematic associations between task performance, and (c) patients with mild, severe and/or non-selective impairments; meaning that the full spectrum of deficits is unknown. The Back of the Brain project assessed the range and specificity of visual perceptual impairment in 64 patients with posterior cerebral artery stroke recruited based on lesion localization and not behavioural performance. Word, object, and face processing were measured with comparable tests across different levels of processing to investigate associations and dissociations across domains. We present two complementary analyses of the extensive behavioural battery: (1) a data-driven analysis of the whole patient group, and (2) a single-subject case-series analysis testing for deficits and dissociations in each individual patient. In both analyses, the general organisational principle was of associations between words, objects, and faces even following unilateral lesions. The majority of patients either showed deficits across all domains or in no domain, suggesting a spectrum of visuo-perceptual deficits post stroke. Dissociations were observed, but they were the exception and not the rule: Category-selective impairments were found in only a minority of patients, all of whom showed disproportionate deficits for words. Interestingly, such selective word impairments were found following both left and right hemisphere lesions. This large-scale investigation of posterior cerebral artery stroke patients highlights the bilateral representation of visual perceptual function.
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Affiliation(s)
- Grace E Rice
- MRC Cognition and Brain Sciences Unit (CBU), University of Cambridge, UK
| | - Sheila J Kerry
- University College London Queen Square Institute of Neurology, UK
| | - Ro J Robotham
- Department of Psychology, University of Copenhagen, Denmark
| | - Alex P Leff
- University College London Queen Square Institute of Neurology, UK
| | | | - Randi Starrfelt
- Department of Psychology, University of Copenhagen, Denmark.
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34
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Castro N. Methodological Considerations for Incorporating Clinical Data Into a Network Model of Retrieval Failures. Top Cogn Sci 2021; 14:111-126. [PMID: 33818913 DOI: 10.1111/tops.12531] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 03/17/2021] [Accepted: 03/17/2021] [Indexed: 12/01/2022]
Abstract
Difficulty retrieving information (e.g., words) from memory is prevalent in neurogenic communication disorders (e.g., aphasia and dementia). Theoretical modeling of retrieval failures often relies on clinical data, despite methodological limitations (e.g., locus of retrieval failure, heterogeneity of individuals, and progression of disorder/disease). Techniques from network science are naturally capable of handling these limitations. This paper reviews recent work using a multiplex lexical network to account for word retrieval failures and highlights how network science can address the limitations of clinical data. Critically, any model we employ could impact clinical practice and patient lives, harkening the need for theoretically well-informed network models.
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Affiliation(s)
- Nichol Castro
- Department of Communicative Disorders and Sciences, University at Buffalo
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35
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Fan JM, Gorno-Tempini ML, Dronkers NF, Miller BL, Berger MS, Chang EF. Data-Driven, Visual Framework for the Characterization of Aphasias Across Stroke, Post-resective, and Neurodegenerative Disorders Over Time. Front Neurol 2020; 11:616764. [PMID: 33447252 PMCID: PMC7801263 DOI: 10.3389/fneur.2020.616764] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 12/03/2020] [Indexed: 12/04/2022] Open
Abstract
Aphasia classifications and specialized language batteries differ across the fields of neurodegenerative disorders and lesional brain injuries, resulting in difficult comparisons of language deficits across etiologies. In this study, we present a simplified framework, in which a widely-used aphasia battery captures clinical clusters across disease etiologies and provides a quantitative and visual method to characterize and track patients over time. The framework is used to evaluate populations representing three disease etiologies: stroke, primary progressive aphasia (PPA), and post-operative aphasia. A total of 330 patients across three populations with cerebral injury leading to aphasia were investigated, including 76 patients with stroke, 107 patients meeting criteria for PPA, and 147 patients following left hemispheric resective surgery. Western Aphasia Battery (WAB) measures (Information Content, Fluency, answering Yes/No questions, Auditory Word Recognition, Sequential Commands, and Repetition) were collected across the three populations and analyzed to develop a multi-dimensional aphasia model using dimensionality reduction techniques. Two orthogonal dimensions were found to explain 87% of the variance across aphasia phenotypes and three disease etiologies. The first dimension reflects shared weighting across aphasia subscores and correlated with aphasia severity. The second dimension incorporates fluency and comprehension, thereby separating Wernicke's from Broca's aphasia, and the non-fluent/agrammatic from semantic PPA variants. Clusters representing clinical classifications, including late PPA presentations, were preserved within the two-dimensional space. Early PPA presentations were not classifiable, as specialized batteries are needed for phenotyping. Longitudinal data was further used to visualize the trajectory of aphasias during recovery or disease progression, including the rapid recovery of post-operative aphasic patients. This method has implications for the conceptualization of aphasia as a spectrum disorder across different disease etiology and may serve as a framework to track the trajectories of aphasia progression and recovery.
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Affiliation(s)
- Joline M Fan
- Department of Neurology, University of California, San Francisco, San Francisco, CA, United States
| | | | - Nina F Dronkers
- Department of Psychology, University of California, Berkeley, Berkeley, CA, United States.,Department of Neurology, University of California, Davis, Davis, CA, United States
| | - Bruce L Miller
- Department of Neurology, University of California, San Francisco, San Francisco, CA, United States
| | - Mitchel S Berger
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA, United States
| | - Edward F Chang
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA, United States
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36
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Ramanan S, Roquet D, Goldberg ZL, Hodges JR, Piguet O, Irish M, Lambon Ralph MA. Establishing two principal dimensions of cognitive variation in logopenic progressive aphasia. Brain Commun 2020; 2:fcaa125. [PMID: 33376980 PMCID: PMC7750924 DOI: 10.1093/braincomms/fcaa125] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 06/25/2020] [Accepted: 07/13/2020] [Indexed: 12/28/2022] Open
Abstract
Logopenic progressive aphasia is a neurodegenerative syndrome characterized by sentence repetition and naming difficulties arising from left-lateralized temporoparietal atrophy. Clinical descriptions of logopenic progressive aphasia largely concentrate on profiling language deficits, however, accumulating evidence points to the presence of cognitive deficits even on tasks with minimal language demands. Although non-linguistic cognitive deficits in logopenic progressive aphasia are thought to scale with disease severity, patients at discrete stages of language dysfunction display overlapping cognitive profiles, suggesting individual-level variation in cognitive performance, independent of primary language dysfunction. To address this issue, we used principal component analysis to decompose the individual-level variation in cognitive performance in 43 well-characterized logopenic progressive aphasia patients who underwent multi-domain neuropsychological assessments and structural neuroimaging. The principal component analysis solution revealed the presence of two, statistically independent factors, providing stable and clinically intuitive explanations for the majority of variance in cognitive performance in the syndrome. Factor 1 reflected 'speech production and verbal memory' deficits which typify logopenic progressive aphasia. Systematic variations were also confirmed on a second, orthogonal factor mainly comprising visuospatial and executive processes. Adopting a case-comparison approach, we further demonstrate that pairs of patients with comparable Factor 1 scores, regardless of their severity, diverge considerably on visuo-executive test performance, underscoring the inter-individual variability in cognitive profiles in comparably 'logopenic' patients. Whole-brain voxel-based morphometry analyses revealed that speech production and verbal memory factor scores correlated with left middle frontal gyrus, while visuospatial and executive factor scores were associated with grey matter intensity of right-lateralized temporoparietal, middle frontal regions and their underlying white matter connectivity. Importantly, logopenic progressive aphasia patients with poorer visuospatial and executive factor scores demonstrated greater right-lateralized temporoparietal and frontal atrophy. Our findings demonstrate the inherent variation in cognitive performance at an individual- and group-level in logopenic progressive aphasia, suggesting the presence of a genuine co-occurring cognitive impairment that is statistically independent of language function and disease severity.
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Affiliation(s)
- Siddharth Ramanan
- The University of Sydney, Brain and Mind Centre, Sydney, NSW, Australia
- The University of Sydney, School of Psychology, Sydney, NSW, Australia
- ARC Centre of Excellence in Cognition and its Disorders, Sydney, NSW, Australia
| | - Daniel Roquet
- The University of Sydney, Brain and Mind Centre, Sydney, NSW, Australia
- The University of Sydney, School of Psychology, Sydney, NSW, Australia
- ARC Centre of Excellence in Cognition and its Disorders, Sydney, NSW, Australia
| | - Zoë-Lee Goldberg
- The University of Sydney, Brain and Mind Centre, Sydney, NSW, Australia
| | - John R Hodges
- The University of Sydney, Brain and Mind Centre, Sydney, NSW, Australia
- ARC Centre of Excellence in Cognition and its Disorders, Sydney, NSW, Australia
- The University of Sydney, School of Medical Sciences, Sydney, NSW, Australia
| | - Olivier Piguet
- The University of Sydney, Brain and Mind Centre, Sydney, NSW, Australia
- The University of Sydney, School of Psychology, Sydney, NSW, Australia
- ARC Centre of Excellence in Cognition and its Disorders, Sydney, NSW, Australia
| | - Muireann Irish
- The University of Sydney, Brain and Mind Centre, Sydney, NSW, Australia
- The University of Sydney, School of Psychology, Sydney, NSW, Australia
- ARC Centre of Excellence in Cognition and its Disorders, Sydney, NSW, Australia
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