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Stockbridge MD, Keser Z, Bonilha L, Hillis AE. Microstructural properties in subacute aphasia: concurrent and prospective relationships underpinning recovery. Brain Struct Funct 2024:10.1007/s00429-024-02826-z. [PMID: 38969934 DOI: 10.1007/s00429-024-02826-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 06/17/2024] [Indexed: 07/07/2024]
Abstract
BACKGROUND Few investigations examined the relationship between microstructural white matter integrity and subacute post-stroke linguistic performance or the relationship between microstructural integrity and the recovery of language function. We examined two key questions: (1) How does subacute language performance, measured in single words and discourse, relate to the microstructural integrity of key white matter regions of interest in the language network? and (2) Does the integrity of these regions before treatment predict the improvement or resolution of linguistic symptoms immediately and chronically following treatment? METHODS 58 participants within the first three months of stroke were enrolled in a randomized, single-center, double-blind, sham-controlled, study of anodal transcranial direct current stimulation combined with a computer-delivered speech and language naming therapy for subacute aphasia and were asked to complete magnetic resonance imaging at enrollment. Microstructural integrity was evaluated using diffusion tensor imaging processed with atlas-based segmentation. Regression and correlation analyses were conducted. RESULTS A subset of 22 participants received diffusion tensor imaging. Picture naming accuracy significantly correlated with lower mean diffusivity (higher microstructural integrity) in the left posterior inferior temporal gyrus. Recovery of naming performance was predicted by days since stroke and baseline microstructural integrity of the left posterior middle temporal gyrus, arcuate fasciculus, and superior longitudinal fasciculus. Recovery of discourse efficiency was significantly predicted by the same model. CONCLUSIONS This study demonstrates an association between picture naming and discourse and microstructural integrity of the key regions in the language network for patients with subacute post-stroke aphasia. Baseline microstructural integrity significantly predicts language recovery.
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Affiliation(s)
- Melissa D Stockbridge
- Department of Neurology, Johns Hopkins University School of Medicine, 600 North Wolfe Street Phipps 4, Suite 446, Baltimore, MD, 21287, USA.
| | - Zafer Keser
- Department of Neurology, Johns Hopkins University School of Medicine, 600 North Wolfe Street Phipps 4, Suite 446, Baltimore, MD, 21287, USA
- Department of Neurology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Leonardo Bonilha
- Department of Neurology, University of South Carolina School of Medicine Columbia, Columbia, SC, 29209, USA
| | - Argye E Hillis
- Department of Neurology, Johns Hopkins University School of Medicine, 600 North Wolfe Street Phipps 4, Suite 446, Baltimore, MD, 21287, USA
- Department of Physical Medicine and Rehabilitation, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA
- Department of Cognitive Science, Krieger School of Arts and Sciences, Johns Hopkins University, Baltimore, MD, 21218, USA
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2
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Teghipco A, Newman-Norlund R, Fridriksson J, Rorden C, Bonilha L. Distinct brain morphometry patterns revealed by deep learning improve prediction of post-stroke aphasia severity. COMMUNICATIONS MEDICINE 2024; 4:115. [PMID: 38866977 PMCID: PMC11169346 DOI: 10.1038/s43856-024-00541-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 06/03/2024] [Indexed: 06/14/2024] Open
Abstract
BACKGROUND Emerging evidence suggests that post-stroke aphasia severity depends on the integrity of the brain beyond the lesion. While measures of lesion anatomy and brain integrity combine synergistically to explain aphasic symptoms, substantial interindividual variability remains unaccounted. One explanatory factor may be the spatial distribution of morphometry beyond the lesion (e.g., atrophy), including not just specific brain areas, but distinct three-dimensional patterns. METHODS Here, we test whether deep learning with Convolutional Neural Networks (CNNs) on whole brain morphometry (i.e., segmented tissue volumes) and lesion anatomy better predicts chronic stroke individuals with severe aphasia (N = 231) than classical machine learning (Support Vector Machines; SVMs), evaluating whether encoding spatial dependencies identifies uniquely predictive patterns. RESULTS CNNs achieve higher balanced accuracy and F1 scores, even when SVMs are nonlinear or integrate linear or nonlinear dimensionality reduction. Parity only occurs when SVMs access features learned by CNNs. Saliency maps demonstrate that CNNs leverage distributed morphometry patterns, whereas SVMs focus on the area around the lesion. Ensemble clustering of CNN saliencies reveals distinct morphometry patterns unrelated to lesion size, consistent across individuals, and which implicate unique networks associated with different cognitive processes as measured by the wider neuroimaging literature. Individualized predictions depend on both ipsilateral and contralateral features outside the lesion. CONCLUSIONS Three-dimensional network distributions of morphometry are directly associated with aphasia severity, underscoring the potential for CNNs to improve outcome prognostication from neuroimaging data, and highlighting the prospective benefits of interrogating spatial dependence at different scales in multivariate feature space.
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Affiliation(s)
- Alex Teghipco
- Department of Communication Sciences and Disorders, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA.
| | - Roger Newman-Norlund
- Department of Psychology, College of Arts and Sciences, University of South Carolina, Columbia, SC, USA
| | - Julius Fridriksson
- Department of Communication Sciences and Disorders, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA
| | - Christopher Rorden
- Department of Psychology, College of Arts and Sciences, University of South Carolina, Columbia, SC, USA
| | - Leonardo Bonilha
- Department of Neurology, School of Medicine, University of South Carolina, Columbia, SC, USA
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3
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Sihvonen AJ, Pitkäniemi A, Siponkoski ST, Kuusela L, Martínez-Molina N, Laitinen S, Särkämö ER, Pekkola J, Melkas S, Schlaug G, Sairanen V, Särkämö T. Structural Neuroplasticity Effects of Singing in Chronic Aphasia. eNeuro 2024; 11:ENEURO.0408-23.2024. [PMID: 38688718 DOI: 10.1523/eneuro.0408-23.2024] [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: 10/13/2023] [Revised: 02/28/2024] [Accepted: 04/18/2024] [Indexed: 05/02/2024] Open
Abstract
Singing-based treatments of aphasia can improve language outcomes, but the neural benefits of group-based singing in aphasia are unknown. Here, we set out to determine the structural neuroplasticity changes underpinning group-based singing-induced treatment effects in chronic aphasia. Twenty-eight patients with at least mild nonfluent poststroke aphasia were randomized into two groups that received a 4-month multicomponent singing intervention (singing group) or standard care (control group). High-resolution T1 images and multishell diffusion-weighted MRI data were collected in two time points (baseline/5 months). Structural gray matter (GM) and white matter (WM) neuroplasticity changes were assessed using language network region of interest-based voxel-based morphometry (VBM) and quantitative anisotropy-based connectometry, and their associations to improved language outcomes (Western Aphasia Battery Naming and Repetition) were evaluated. Connectometry analyses showed that the singing group enhanced structural WM connectivity in the left arcuate fasciculus (AF) and corpus callosum as well as in the frontal aslant tract (FAT), superior longitudinal fasciculus, and corticostriatal tract bilaterally compared with the control group. Moreover, in VBM, the singing group showed GM volume increase in the left inferior frontal cortex (Brodmann area 44) compared with the control group. The neuroplasticity effects in the left BA44, AF, and FAT correlated with improved naming abilities after the intervention. These findings suggest that in the poststroke aphasia group, singing can bring about structural neuroplasticity changes in left frontal language areas and in bilateral language pathways, which underpin treatment-induced improvement in speech production.
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Affiliation(s)
- Aleksi J Sihvonen
- Cognitive Brain Research Unit and Centre of Excellence in Music, Mind, Body and Brain, Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki 00014, Finland
- School of Health and Rehabilitation Sciences, Queensland Aphasia Research Centre and UQ Centre for Clinical Research, The University of Queensland, Brisbane QLD 4072, Australia
- Department of Neurology, University of Helsinki and Helsinki University Hospital, Helsinki 00029, Finland
| | - Anni Pitkäniemi
- Cognitive Brain Research Unit and Centre of Excellence in Music, Mind, Body and Brain, Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki 00014, Finland
| | - Sini-Tuuli Siponkoski
- Cognitive Brain Research Unit and Centre of Excellence in Music, Mind, Body and Brain, Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki 00014, Finland
| | - Linda Kuusela
- HUS Helsinki Medical Imaging Center, Helsinki University Hospital, Helsinki 00029, Finland
| | - Noelia Martínez-Molina
- Cognitive Brain Research Unit and Centre of Excellence in Music, Mind, Body and Brain, Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki 00014, Finland
| | | | | | - Johanna Pekkola
- HUS Helsinki Medical Imaging Center, Helsinki University Hospital, Helsinki 00029, Finland
| | - Susanna Melkas
- Department of Neurology, University of Helsinki and Helsinki University Hospital, Helsinki 00029, Finland
| | - Gottfried Schlaug
- Department of Neurology, UMass Medical School, Springfield, Massachusetts 01655
- Department of Biomedical Engineering and Institute of Applied Life Sciences, UMass Amherst, Amherst, Massachusetts 01655
| | - Viljami Sairanen
- HUS Helsinki Medical Imaging Center, Helsinki University Hospital, Helsinki 00029, Finland
| | - Teppo Särkämö
- Cognitive Brain Research Unit and Centre of Excellence in Music, Mind, Body and Brain, Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki 00014, Finland
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Tilton-Bolowsky V, Stockbridge MD, Hillis AE. Remapping and Reconnecting the Language Network after Stroke. Brain Sci 2024; 14:419. [PMID: 38790398 PMCID: PMC11117613 DOI: 10.3390/brainsci14050419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Revised: 04/22/2024] [Accepted: 04/23/2024] [Indexed: 05/26/2024] Open
Abstract
Here, we review the literature on neurotypical individuals and individuals with post-stroke aphasia showing that right-hemisphere regions homologous to language network and other regions, like the right cerebellum, are activated in language tasks and support language even in healthy people. We propose that language recovery in post-stroke aphasia occurs largely by potentiating the right hemisphere network homologous to the language network and other networks that previously supported language to a lesser degree and by modulating connection strength between nodes of the right-hemisphere language network and undamaged nodes of the left-hemisphere language network. Based on this premise (supported by evidence we review), we propose that interventions should be aimed at potentiating the right-hemisphere language network through Hebbian learning or by augmenting connections between network nodes through neuroplasticity, such as non-invasive brain stimulation and perhaps modulation of neurotransmitters involved in neuroplasticity. We review aphasia treatment studies that have taken this approach. We conclude that further aphasia rehabilitation with this aim is justified.
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Affiliation(s)
| | | | - Argye E. Hillis
- Departments of Neurology, Physical Medicine & Rehabilitation, and Cognitive Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (V.T.-B.); (M.D.S.)
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Falconer I, Varkanitsa M, Kiran S. Resting-state brain network connectivity is an independent predictor of responsiveness to language therapy in chronic post-stroke aphasia. Cortex 2024; 173:296-312. [PMID: 38447266 PMCID: PMC11188988 DOI: 10.1016/j.cortex.2023.11.022] [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: 08/25/2022] [Revised: 05/11/2023] [Accepted: 11/29/2023] [Indexed: 03/08/2024]
Abstract
Post-stroke aphasia recovery, especially in the chronic phase, is challenging to predict. Functional integrity of the brain and brain network topology have been suggested as biomarkers of language recovery. This study sought to investigate functional connectivity in four predefined brain networks (i.e., language, default mode, dorsal attention, and salience networks), in relation to aphasia severity and response to language therapy. Thirty patients with chronic post-stroke aphasia were recruited and received a treatment targeting word finding. Structural and functional brain scans were acquired at baseline and resting state functional connectivity for each network was calculated. Additionally, graph measures quantifying network properties were calculated for each network. These included global efficiency for all networks and average strength and clustering coefficient for the language network. Linear mixed effects models showed that mean functional connectivity in the default mode, dorsal attention, and salience networks as well as graph measures of all four networks are independent predictors of response to therapy. While greater mean functional connectivity and global efficiency of the dorsal attention and salience networks predicted greater treatment response, greater mean functional connectivity and global efficiency in the default mode network predicted poorer treatment response. Results for the language network were more nuanced with more efficient network configurations (as reflected in graph measures), but not mean functional connectivity, predicting greater treatment response. These findings highlight the prognostic value of resting-state functional connectivity in chronic treatment-induced aphasia recovery.
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Affiliation(s)
- Isaac Falconer
- Center for Brain Recovery, Boston University, Boston, MA, USA.
| | | | - Swathi Kiran
- Center for Brain Recovery, Boston University, Boston, MA, USA
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Billot A, Kiran S. Disentangling neuroplasticity mechanisms in post-stroke language recovery. BRAIN AND LANGUAGE 2024; 251:105381. [PMID: 38401381 PMCID: PMC10981555 DOI: 10.1016/j.bandl.2024.105381] [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] [Received: 07/20/2023] [Revised: 11/28/2023] [Accepted: 01/12/2024] [Indexed: 02/26/2024]
Abstract
A major objective in post-stroke aphasia research is to gain a deeper understanding of neuroplastic mechanisms that drive language recovery, with the ultimate goal of enhancing treatment outcomes. Subsequent to recent advances in neuroimaging techniques, we now have the ability to examine more closely how neural activity patterns change after a stroke. However, the way these neural activity changes relate to language impairments and language recovery is still debated. The aim of this review is to provide a theoretical framework to better investigate and interpret neuroplasticity mechanisms underlying language recovery in post-stroke aphasia. We detail two sets of neuroplasticity mechanisms observed at the synaptic level that may explain functional neuroimaging findings in post-stroke aphasia recovery at the network level: feedback-based homeostatic plasticity and associative Hebbian plasticity. In conjunction with these plasticity mechanisms, higher-order cognitive control processes dynamically modulate neural activity in other regions to meet communication demands, despite reduced neural resources. This work provides a network-level neurobiological framework for understanding neural changes observed in post-stroke aphasia and can be used to define guidelines for personalized treatment development.
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Affiliation(s)
- Anne Billot
- Center for Brain Recovery, Boston University, Boston, USA; Department of Psychology, Center for Brain Science, Harvard University, Cambridge, Massachusetts, USA; Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Swathi Kiran
- Center for Brain Recovery, Boston University, Boston, USA.
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Bonilha L, Rorden C, Roth R, Sen S, George MS, Fridriksson J. Improved naming in patients with Broca's aphasia with tDCS. J Neurol Neurosurg Psychiatry 2024; 95:273-276. [PMID: 38071545 DOI: 10.1136/jnnp-2023-331541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 08/23/2023] [Indexed: 12/22/2023]
Abstract
BACKGROUND Language impairment (aphasia) is a common neurological deficit after strokes. For individuals with chronic aphasia (beyond 6 months after the stroke), language improvements with speech therapy (ST) are often limited. Transcranial direct current stimulation (tDCS) is a promising approach to complement language recovery but interindividual variability in treatment response is common after tDCS, suggesting a possible relationship between tDCS and type of linguistic impairment (aphasia type). METHODS This current study is a subgroup analysis of a randomised controlled phase II futility design clinical trial on tDCS in chronic post-stroke aphasia. All participants received ST coupled with tDCS (n=31) vs sham tDCS (n=39). Confrontation naming was tested at baseline, and 1, 4, and 24 weeks post-treatment. RESULTS Broca's aphasia was associated with maximal adjunctive benefit of tDCS, with an average improvement of 10 additional named items with tDCS+ST compared with ST alone at 4 weeks post-treatment. In comparison, tDCS was not associated with significant benefits for other aphasia types F(1)=4.23, p=0.04. Among participants with Broca's aphasia, preservation of the perilesional posterior inferior temporal cortex was associated with higher treatment benefit (R=0.35, p=0.03). CONCLUSIONS These results indicate that adjuvant tDCS can enhance ST to treat naming in Broca's aphasia, and this may guide intervention approaches in future studies.
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Affiliation(s)
- Leonardo Bonilha
- Neurology, University of South Carolina School of Medicine, Columbia, South Carolina, USA
| | - Chris Rorden
- Psychology, University of South Carolina, Columbia, South Carolina, USA
| | - Rebecca Roth
- Neurology, Emory University, Atlanta, Georgia, USA
| | - Souvik Sen
- Neurology, University of South Carolina School of Medicine, Columbia, South Carolina, USA
| | - Mark S George
- Psychiatry, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Julius Fridriksson
- Communication Sciences and Disorders, University of South Carolina, Columbia, South Carolina, USA
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Varkanitsa M, Kiran S. Insights gained over 60 years on factors shaping post-stroke aphasia recovery: A commentary on Vignolo (1964). Cortex 2024; 170:90-100. [PMID: 38123405 PMCID: PMC10962385 DOI: 10.1016/j.cortex.2023.12.002] [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: 10/31/2023] [Revised: 12/01/2023] [Accepted: 12/04/2023] [Indexed: 12/23/2023]
Abstract
Aphasia is an acquired language disorder resulting from brain injury, including strokes which is the most common etiology, neurodegenerative diseases, tumors, traumatic brain injury, and resective surgery. Aphasia affects a significant portion of stroke survivors, with approximately one third experiencing its debilitating effects in the long term. Despite its challenges, there is growing evidence that recovery from aphasia is possible, even in the chronic phase of stroke. Sixty years ago, Vignolo (1964) outlined the primary challenges confronted by researchers in this field. These challenges encompassed the absence of an objective evaluation of language difficulties, the scarcity of evidence regarding spontaneous aphasia recovery, and the presence of numerous variables that could potentially influence the process of aphasia recovery. In this paper, we discuss the remarkable progress that has been made in the assessment of language and communication in aphasia as well as in understanding the factors influencing post-stroke aphasia recovery.
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Affiliation(s)
| | - Swathi Kiran
- Center for Brain Recovery, Boston University, USA
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Ding J, Middleton EL, Mirman D. Impaired discourse content in aphasia is associated with frontal white matter damage. Brain Commun 2023; 5:fcad310. [PMID: 38025278 PMCID: PMC10664411 DOI: 10.1093/braincomms/fcad310] [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: 12/23/2022] [Revised: 09/04/2023] [Accepted: 11/09/2023] [Indexed: 12/01/2023] Open
Abstract
Aphasia is a common consequence of stroke with severe impacts on employability, social interactions and quality of life. Producing discourse-relevant information in a real-world setting is the most important aspect of recovery because it is critical to successful communication. This study sought to identify the lesion correlates of impaired production of relevant information in spoken discourse in a large, unselected sample of participants with post-stroke aphasia. Spoken discourse (n = 80) and structural brain scans (n = 66) from participants with aphasia following left hemisphere stroke were analysed. Each participant provided 10 samples of spoken discourse elicited in three different genres, and 'correct information unit' analysis was used to quantify the informativeness of speech samples. The lesion correlates were identified using multivariate lesion-symptom mapping, voxel-wise disconnection and tract-wise analyses. Amount and speed of relevant information were highly correlated across different genres and with total lesion size. The analyses of lesion correlates converged on the same pattern: impaired production of relevant information was associated with damage to anterior dorsal white matter pathways, specifically the arcuate fasciculus, frontal aslant tract and superior longitudinal fasciculus. Damage to these pathways may be a useful biomarker for impaired informative spoken discourse and informs development of neurorehabilitation strategies.
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Affiliation(s)
- Junhua Ding
- Department of Psychology, University of Edinburgh, Edinburgh EH8 9JZ, UK
| | | | - Daniel Mirman
- Department of Psychology, University of Edinburgh, Edinburgh EH8 9JZ, UK
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Kim TH, Yoon MK, Choi SG, Kim JS, Choi JL. Patient With Crossed Aphasia Undergoing Long-Term Speech Therapy: A Case Report. BRAIN & NEUROREHABILITATION 2023; 16:e23. [PMID: 38047091 PMCID: PMC10689864 DOI: 10.12786/bn.2023.16.e23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 08/21/2023] [Accepted: 08/31/2023] [Indexed: 12/05/2023] Open
Abstract
Crossed aphasia (CA) is a type of aphasia caused by cerebral hemispheric lesions on the same side of the dominant hand. The prevalence of CA is extremely rare. To the best of our knowledge, this is the first case report in Korea to conduct 6 years of long-term speech therapy in a case of a patient with CA. The patient was a 57-year-old right-handed man with aphasia caused by extensive acute infarction in the right middle cerebral artery territory. He presented with global aphasia, right-left disorientation, and agraphia. Language function recovered in the first 6 months and then plateaued.
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Affiliation(s)
- Tae-Hwan Kim
- Department of Physical Medicine and Rehabilitation and Medical Device Clinical Trial Center, Presbyterian Medical Center, Jeonju, Korea
| | - Myeong-Kwon Yoon
- Department of Physical Medicine and Rehabilitation and Medical Device Clinical Trial Center, Presbyterian Medical Center, Jeonju, Korea
| | - Seung-Gue Choi
- Department of Physical Medicine and Rehabilitation and Medical Device Clinical Trial Center, Presbyterian Medical Center, Jeonju, Korea
| | - Jeong-Seob Kim
- Department of Physical Medicine and Rehabilitation and Medical Device Clinical Trial Center, Presbyterian Medical Center, Jeonju, Korea
| | - Jyul-Lee Choi
- Department of Physical Medicine and Rehabilitation and Medical Device Clinical Trial Center, Presbyterian Medical Center, Jeonju, Korea
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Varkanitsa M, Peñaloza C, Charidimou A, Kiran S. Cerebral Small Vessel Disease Burden: An Independent Biomarker for Anomia Treatment Responsiveness in Chronic Stroke Patients With Aphasia. Arch Phys Med Rehabil 2023; 104:1630-1637. [PMID: 37290492 PMCID: PMC10543408 DOI: 10.1016/j.apmr.2023.05.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 03/31/2023] [Accepted: 05/08/2023] [Indexed: 06/10/2023]
Abstract
OBJECTIVE To determine whether MRI-based cerebral small vessel disease (cSVD) burden predicts treatment-induced aphasia recovery in chronic stroke patients above and beyond initial aphasia severity and stroke-lesion volume. DESIGN Retrospective. Four cSVD neuroimaging markers were rated using validated visual scales: white matter hyperintensities, enlarged perivascular spaces, lacunes, and global cortical atrophy. We also calculated a cSVD total score. We employed linear regression models to model treatment response as a function of cSVD burden. We also ran correlation analyses to determine the association among cSVD burden and pre-treatment linguistic and non-linguistic cognition. SETTING Research clinic. PARTICIPANTS The study includes data from 30 chronic stroke patients with aphasia who received treatment for word finding difficulties and completed additional pre-treatment neuroimaging and behavioral assessments (N=30). INTERVENTIONS 120-minute sessions of anomia treatment 2 times per week for up to 12 weeks. MAIN OUTCOME MEASURES Change in accuracy on the treatment probes measured as a percentage (ie, change in accuracy percentage score=post-treatment accuracy percentage minus pre-treatment accuracy percentage). RESULTS Baseline cSVD burden predicted response to anomia treatment independently from demographic and stroke-related factors. Patients with lower cSVD burden exhibited enhanced rehabilitation response compared with those with higher cSVD burden (β=-6.816e-02, P=.019). cSVD burden was highly associated with nonverbal executive function at baseline (r=-0.49, P=.005): patients with lower cSVD burden exhibited higher performance on nonverbal executive function tasks compared with participants with higher cSVD burden. No association was observed among cSVD burden and performance on language tasks at the baseline. CONCLUSIONS cSVD, a marker of brain reserve and a robust risk factor for post-stroke dementia, may be used as a biomarker for distinguishing patients who are more likely to respond to anomia therapy from those who are less likely to do so and for individualizing treatment parameters (eg, targeting both linguistic and nonlinguistic cognition in severe cSVD).
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Affiliation(s)
- Maria Varkanitsa
- Center for Brain Recovery, Sargent College of Health and Rehabilitation Sciences, Boston University, Boston, MA.
| | - Claudia Peñaloza
- Department of Cognition, Development and Educational Psychology, Faculty of Psychology, University of Barcelona, Barcelona, Spain; Institute of Neurosciences, University of Barcelona, Barcelona, Spain; Cognition and Brain Plasticity Unit, Bellvitge Biomedical Research Institute-IDIBELL, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Andreas Charidimou
- Department of Neurology, Boston University Medical Center and Boston University School of Medicine, MA
| | - Swathi Kiran
- Center for Brain Recovery, Sargent College of Health and Rehabilitation Sciences, Boston University, Boston, MA
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12
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Neophytou K, Wiley R, Litovsky C, Tsapkini K, Rapp B. The right hemisphere's capacity for language: evidence from primary progressive aphasia. Cereb Cortex 2023; 33:9971-9985. [PMID: 37522277 PMCID: PMC10502784 DOI: 10.1093/cercor/bhad258] [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: 01/06/2023] [Revised: 06/21/2023] [Accepted: 06/22/2023] [Indexed: 08/01/2023] Open
Abstract
The role of the right hemisphere (RH) in core language processes is still a matter of intense debate. Most of the relevant evidence has come from studies of gray matter, with relatively little research on RH white matter (WM) connectivity. Using Diffusion Tensor Imaging-based tractography, the current work examined the role of the two hemispheres in language processing in 33 individuals with Primary Progressive Aphasia (PPA), aiming to better characterize the contribution of the RH to language processing in the context of left hemisphere (LH) damage. The findings confirm the impact of PPA on the integrity of the WM language tracts in the LH. Additionally, an examination of the relationship between tract integrity and language behaviors provides robust evidence of the involvement of the WM language tracts of both hemispheres in language processing in PPA. Importantly, this study provides novel evidence of a unique contribution of the RH to language processing (i.e. a contribution independent from that of the language-dominant LH). Finally, we provide evidence that the RH contribution is specific to language processing rather than being domain general. These findings allow us to better characterize the role of RH in language processing, particularly in the context of LH damage.
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Affiliation(s)
- Kyriaki Neophytou
- Department of Neurology, Johns Hopkins Medicine, Baltimore, MD, United States
| | - Robert Wiley
- Department of Psychology, University of North Carolina at Greensboro, Greensboro, NC, United States
- Department of Cognitive Science, Johns Hopkins University, Baltimore, MD, United States
| | - Celia Litovsky
- Department of Cognitive Science, Johns Hopkins University, Baltimore, MD, United States
| | - Kyrana Tsapkini
- Department of Neurology, Johns Hopkins Medicine, Baltimore, MD, United States
- Department of Cognitive Science, Johns Hopkins University, Baltimore, MD, United States
| | - Brenda Rapp
- Department of Cognitive Science, Johns Hopkins University, Baltimore, MD, United States
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Simic T, Desjardins MÈ, Courson M, Bedetti C, Houzé B, Brambati SM. Treatment-induced neuroplasticity after anomia therapy in post-stroke aphasia: A systematic review of neuroimaging studies. BRAIN AND LANGUAGE 2023; 244:105300. [PMID: 37633250 DOI: 10.1016/j.bandl.2023.105300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 05/02/2023] [Accepted: 06/21/2023] [Indexed: 08/28/2023]
Abstract
We systematically reviewed the literature on neural changes following anomia treatment post-stroke. We conducted electronic searches of CINAHL, Cochrane Trials, Embase, Ovid MEDLINE, MEDLINE-in-Process and PsycINFO databases; two independent raters assessed all abstracts and full texts. Accepted studies reported original data on adults with post-stroke aphasia, who received behavioural treatment for anomia, and magnetic resonance brain imaging (MRI) pre- and post-treatment. Search results yielded 2481 citations; 33 studies were accepted. Most studies employed functional MRI and the quality of reporting neuroimaging methodology was variable, particularly for pre-processing steps and statistical analyses. The most methodologically robust data were synthesized, focusing on pre- versus post-treatment contrasts. Studies more commonly reported increases (versus decreases) in activation following naming therapy, primarily in the left supramarginal gyrus, and left/bilateral precunei. Our findings highlight the methodological heterogeneity across MRI studies, and the paucity of robust evidence demonstrating direct links between brain and behaviour in anomia rehabilitation.
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Affiliation(s)
- Tijana Simic
- Centre de Recherche de l'Institut Universitaire de Gériatrie de Montréal (CRIUGM), 4545 Queen Mary R.d., Montréal, QC H3W 1W4, Canada; Département de Psychologie, Université de Montréal, 90 Vincent-d'Indy Avenue, Montréal, QC H2V 2S9, Canada; Hôpital du Sacré-Cœur de Montréal (HSCM), 5400 Boul Gouin O, Montréal, QC H4J 1C5, Canada.
| | - Marie-Ève Desjardins
- Centre de Recherche de l'Institut Universitaire de Gériatrie de Montréal (CRIUGM), 4545 Queen Mary R.d., Montréal, QC H3W 1W4, Canada; Département de Psychologie, Université de Montréal, 90 Vincent-d'Indy Avenue, Montréal, QC H2V 2S9, Canada; Hôpital du Sacré-Cœur de Montréal (HSCM), 5400 Boul Gouin O, Montréal, QC H4J 1C5, Canada
| | - Melody Courson
- Centre de Recherche de l'Institut Universitaire de Gériatrie de Montréal (CRIUGM), 4545 Queen Mary R.d., Montréal, QC H3W 1W4, Canada; Département de Psychologie, Université de Montréal, 90 Vincent-d'Indy Avenue, Montréal, QC H2V 2S9, Canada
| | - Christophe Bedetti
- Centre de Recherche de l'Institut Universitaire de Gériatrie de Montréal (CRIUGM), 4545 Queen Mary R.d., Montréal, QC H3W 1W4, Canada
| | - Bérengère Houzé
- Centre de Recherche de l'Institut Universitaire de Gériatrie de Montréal (CRIUGM), 4545 Queen Mary R.d., Montréal, QC H3W 1W4, Canada; Département de Psychologie, Université de Montréal, 90 Vincent-d'Indy Avenue, Montréal, QC H2V 2S9, Canada
| | - Simona Maria Brambati
- Centre de Recherche de l'Institut Universitaire de Gériatrie de Montréal (CRIUGM), 4545 Queen Mary R.d., Montréal, QC H3W 1W4, Canada; Département de Psychologie, Université de Montréal, 90 Vincent-d'Indy Avenue, Montréal, QC H2V 2S9, Canada; Hôpital du Sacré-Cœur de Montréal (HSCM), 5400 Boul Gouin O, Montréal, QC H4J 1C5, Canada
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Hannan J, Wilmskoetter J, Fridriksson J, Hillis AE, Bonilha L, Busby N. Brain health imaging markers, post-stroke aphasia and Cognition: A scoping review. Neuroimage Clin 2023; 39:103480. [PMID: 37536153 PMCID: PMC10412866 DOI: 10.1016/j.nicl.2023.103480] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 07/18/2023] [Accepted: 07/19/2023] [Indexed: 08/05/2023]
Abstract
For the past decade, brain health has been an emerging line of scientific inquiry assessing the impact of age-related neurostructural changes on cognitive decline and recovery from brain injury. Typically, compromised brain health is attributed to the presence of small vessel disease (SVD) and brain tissue atrophy, which are represented by various neuroimaging features. However, to date, the relationship between brain health markers and chronic aphasia severity remains unclear. Thus, the goal of this scoping review was to assess the current body of evidence regarding the relationship between SVD-related brain health biomarkers and post-stroke aphasia and cognition. In all, 187 articles were identified from 3 databases, of which 16 articles met the criteria for inclusion. Among these studies, 11 focused on cognition rather than aphasia, while 2 investigated both. Of the 10 studies that used white matter hyperintensities (WMHs) as an indicator of SVD severity, 8 studies (80%) demonstrated a relationship between WMH load and worse cognition in stroke patients. Interestingly, among the studies that specifically investigated aphasia, all 5 studies (100%) demonstrated a relationship between SVD and worse language performance. They also indicated that factors other than brain health (e.g., lesion, age, time post onset) played an important role in determining aphasia severity at a single timepoint. These findings suggest that brain health is likely a crucial factor in the context of aphasia recovery, possibly indicating the necessity of cognitive reserve thresholds for the multimodal cognitive demands associated with language recovery. While SVD and structural brain health are not commonly considered as predictors of aphasia severity, more comprehensive models incorporating brain health have the potential to improve prognosis of post-stroke cognitive and language deficits. Given the variability in the existing literature, a uniform grading system for overall SVD would be beneficial for future research on the mechanisms related to brain networks and neuroplasticity, and their translational impact.
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Affiliation(s)
- Jade Hannan
- Department of Communication Sciences and Disorders, University of South Carolina, Columbia, SC, USA.
| | - Janina Wilmskoetter
- Department of Health and Rehabilitation Sciences, Medical University of South Carolina, Charleston, SC, USA
| | - Julius Fridriksson
- Department of Communication Sciences and Disorders, University of South Carolina, Columbia, SC, USA
| | - Argye E Hillis
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA; Department of Physical Medicine, Rehabilitation, and Cognitive Science, Johns Hopkins University, Baltimore, MD, USA
| | | | - Natalie Busby
- Department of Communication Sciences and Disorders, University of South Carolina, Columbia, SC, USA
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Teghipco A, Newman-Norlund R, Fridriksson J, Rorden C, Bonilha L. Distinct brain morphometry patterns revealed by deep learning improve prediction of aphasia severity. RESEARCH SQUARE 2023:rs.3.rs-3126126. [PMID: 37461696 PMCID: PMC10350198 DOI: 10.21203/rs.3.rs-3126126/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/28/2023]
Abstract
Emerging evidence suggests that post-stroke aphasia severity depends on the integrity of the brain beyond the stroke lesion. While measures of lesion anatomy and brain integrity combine synergistically to explain aphasic symptoms, significant interindividual variability remains unaccounted for. A possible explanatory factor may be the spatial distribution of brain atrophy beyond the lesion. This includes not just the specific brain areas showing atrophy, but also distinct three-dimensional patterns of atrophy. Here, we tested whether deep learning with Convolutional Neural Networks (CNN) on whole brain morphometry (i.e., segmented tissue volumes) and lesion anatomy can better predict which individuals with chronic stroke (N=231) have severe aphasia, and whether encoding spatial dependencies in the data might be capable of improving predictions by identifying unique individualized spatial patterns. We observed that CNN achieves significantly higher accuracy and F1 scores than Support Vector Machine (SVM), even when the SVM is nonlinear or integrates linear and nonlinear dimensionality reduction techniques. Performance parity was only achieved when the SVM was directly trained on the latent features learned by the CNN. Saliency maps demonstrated that the CNN leveraged widely distributed patterns of brain atrophy predictive of aphasia severity, whereas the SVM focused almost exclusively on the area around the lesion. Ensemble clustering of CNN saliency maps revealed distinct morphometry patterns that were unrelated to lesion size, highly consistent across individuals, and implicated unique brain networks associated with different cognitive processes as measured by the wider neuroimaging literature. Individualized predictions of severity depended on both ipsilateral and contralateral features outside of the location of stroke. Our findings illustrate that three-dimensional network distributions of atrophy in individuals with aphasia are directly associated with aphasia severity, underscoring the potential for deep learning to improve prognostication of behavioral outcomes from neuroimaging data, and highlighting the prospective benefits of interrogating spatial dependence at different scales in multivariate feature space.
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Li T, Feng J, Hu R, Lv M, Chang W, Ma X, Qi W, Zhang Y, Chen X, Ding L, Gu Y, Xu W. Effect and safety of C7 neurotomy at the intervertebral foramen in patients with chronic poststroke aphasia: a multicentre, randomised, controlled study protocol. BMJ Open 2023; 13:e065173. [PMID: 37130672 PMCID: PMC10163524 DOI: 10.1136/bmjopen-2022-065173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/04/2023] Open
Abstract
INTRODUCTION Aphasia affects many stroke survivors; therefore, effective treatments are urgently needed. Preliminary clinical findings have suggested an association between contralateral C7-C7 cross nerve transfer and recovery from chronic aphasia. Randomised controlled trials supporting the efficacy of C7 neurotomy (NC7) are lacking. This study will explore the efficacy of NC7 at the intervertebral foramen for improving chronic poststroke aphasia. METHODS AND ANALYSIS This study protocol reports a multicentre, randomised, assessor-blinded active-controlled trial. A total of 50 patients with chronic poststroke aphasia for over 1 year and with a aphasia quotient calculated by Western Aphasia Battery Aphasia Quotient (WAB-AQ) score below 93.8 will be recruited. Participants will be randomly assigned to 1 of 2 groups (25 individuals each) to receive NC7 plus intensive speech and language therapy (iSLT), or iSLT alone programme. The primary outcome is the change in Boston Naming Test score from baseline to the first follow-up after NC7 plus 3 weeks of iSLT or iSLT alone. The secondary outcomes include the changes in the WAB-AQ, Communication Activities of Daily Living-3, International Classification of Functioning, Disability and Health (ICF) speech language function, Barthel Index, Stroke Aphasic Depression Questionnaire-hospital version and sensorimotor assessments. The study will also collect functional imaging outcomes of naming and semantic violation tasks through functional MRI and electroencephalogram to evaluate the intervention-induced neuroplasticity. ETHICS AND DISSEMINATION This study was approved by the institutional review boards of Huashan Hospital, Fudan University, and all participating institutions. The study findings will be disseminated through peer-reviewed publications and conference presentations. TRIAL REGISTRATION NUMBER ChiCTR2200057180.
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Affiliation(s)
- Tie Li
- Department of Hand Surgery, Huashan Hospital, Fudan University, Shanghai, People's Republic of China
- Department of Hand and Upper Extremity Surgery, Limb Function Reconstruction Center, Jing'an District Central Hospital, Shanghai, People's Republic of China
- National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, People's Republic of China
- Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai, People's Republic of China
- Shanghai Key Laboratory of Peripheral Nerve and Microsurgery, Shanghai, People's Republic of China
| | - Juntao Feng
- Department of Hand Surgery, Huashan Hospital, Fudan University, Shanghai, People's Republic of China
- Department of Hand and Upper Extremity Surgery, Limb Function Reconstruction Center, Jing'an District Central Hospital, Shanghai, People's Republic of China
- National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, People's Republic of China
- Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai, People's Republic of China
- Shanghai Key Laboratory of Peripheral Nerve and Microsurgery, Shanghai, People's Republic of China
| | - Ruiping Hu
- Department of Rehabilitation, Huashan Hospital, Fudan University, Shanghai, People's Republic of China
| | - Minzhi Lv
- Center of Evidence-Based Medicine, Department of Biostatistics, School of Public Health, Fudan University, Shanghai, People's Republic of China
| | - Wenshuo Chang
- Institute of Linguistics, Shanghai International Studies University, Shanghai, People's Republic of China
| | - Xingyi Ma
- Department of Hand Surgery, Huashan Hospital, Fudan University, Shanghai, People's Republic of China
| | - Wenjun Qi
- Department of Hand Surgery, Huashan Hospital, Fudan University, Shanghai, People's Republic of China
| | - Ying Zhang
- Department of Rehabilitation, Shanghai Xuhui Central Hospital, Shanghai, People's Republic of China
| | - Xiuen Chen
- Department of Rehabilitation, Huadong Hospital Affiliated to Fudan University, Shanghai, People's Republic of China
| | - Ling Ding
- Department of Rehabilitation, Shanghai Pudong Hospital, Shanghai, People's Republic of China
| | - Yudong Gu
- Department of Hand Surgery, Huashan Hospital, Fudan University, Shanghai, People's Republic of China
- Department of Hand and Upper Extremity Surgery, Limb Function Reconstruction Center, Jing'an District Central Hospital, Shanghai, People's Republic of China
- National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, People's Republic of China
- Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai, People's Republic of China
- Shanghai Key Laboratory of Peripheral Nerve and Microsurgery, Shanghai, People's Republic of China
| | - Wendong Xu
- Department of Hand Surgery, Huashan Hospital, Fudan University, Shanghai, People's Republic of China
- Department of Hand and Upper Extremity Surgery, Limb Function Reconstruction Center, Jing'an District Central Hospital, Shanghai, People's Republic of China
- National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, People's Republic of China
- Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai, People's Republic of China
- Shanghai Key Laboratory of Peripheral Nerve and Microsurgery, Shanghai, People's Republic of China
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Zevgolatakou E, Thye M, Mirman D. Behavioural and neural structure of fluent speech production deficits in aphasia. Brain Commun 2022; 5:fcac327. [PMID: 36601623 PMCID: PMC9798301 DOI: 10.1093/braincomms/fcac327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 09/03/2022] [Accepted: 12/12/2022] [Indexed: 12/15/2022] Open
Abstract
Deficits in fluent speech production following left hemisphere stroke are a central concern because of their impact on patients' lives and the insight they provide about the neural organization of language processing. Fluent speech production requires the rapid coordination of phonological, semantic, and syntactic processing, so this study examined how deficits in connected speech relate to these language sub-systems. Behavioural data (N = 69 participants with aphasia following left hemisphere stroke) consisted of a diverse and comprehensive set of narrative speech production measures and measures of overall severity, semantic deficits, and phonological deficits. These measures were entered into a principal component analysis with bifactor rotation-a latent structure model where each item loads on a general factor that reflects what is common among the items, and orthogonal factors that explain variance not accounted for by the general factor. Lesion data were available for 58 of the participants, and each factor score was analysed with multivariate lesion-symptom mapping. Effects of connectivity disruption were evaluated using robust regression with tract disconnection or graph theoretic measures of connectivity as predictors. The principal component analysis produced a four-factor solution that accounted for 70.6% of the variance in the data, with a general factor corresponding to the overall severity and length and complexity of speech output (complexity factor), a lexical syntax factor, and independent factors for Semantics and Phonology. Deficits in the complexity of speech output were associated with a large temporo-parietal region, similar to overall aphasia severity. The lexical syntax factor was associated with damage in a relatively small set of fronto-parietal regions which may reflect the recruitment of control systems to support retrieval and correct usage of lexical items that primarily serve a syntactic rather than semantic function. Tract-based measures of connectivity disruption were not statistically associated with the deficit scores after controlling for overall lesion volume. Language network efficiency and average clustering coefficient within the language network were significantly associated with deficit scores after controlling for overall lesion volume. These results highlight overall severity as the critical contributor to fluent speech in post-stroke aphasia, with a dissociable factor corresponding to lexical syntax.
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Affiliation(s)
- Eleni Zevgolatakou
- Department of Psychology, University of Edinburgh, 7 George Square, Edinburgh EH8 9JZ, UK
| | - Melissa Thye
- Department of Psychology, University of Edinburgh, 7 George Square, Edinburgh EH8 9JZ, UK
| | - Daniel Mirman
- Correspondence to: Daniel Mirman Department of Psychology, 7 George Square Edinburgh EH8 9JZ, UK E-mail:
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18
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Schevenels K, Gerrits R, Lemmens R, De Smedt B, Zink I, Vandermosten M. Early white matter connectivity and plasticity in post stroke aphasia recovery. Neuroimage Clin 2022; 36:103271. [PMID: 36510409 PMCID: PMC9723316 DOI: 10.1016/j.nicl.2022.103271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 10/30/2022] [Accepted: 11/17/2022] [Indexed: 11/21/2022]
Abstract
A disruption of white matter connectivity is negatively associated with language (recovery) in patients with aphasia after stroke, and behavioral gains have been shown to coincide with white matter neuroplasticity. However, most brain-behavior studies have been carried out in the chronic phase after stroke, with limited generalizability to earlier phases. Furthermore, few studies have investigated neuroplasticity patterns during spontaneous recovery (i.e., not related to a specific treatment) in the first months after stroke, hindering the investigation of potential early compensatory mechanisms. Finally, the majority of previous research has focused on damaged left hemisphere pathways, while neglecting the potential protective value of their right hemisphere counterparts for language recovery. To address these outstanding issues, we present a longitudinal study of thirty-two patients with aphasia (21 males and 11 females, M = 69.47 years, SD = 10.60 years) who were followed up for a period of 1 year with test moments in the acute (1-2 weeks), subacute (3-6 months) and chronic phase (9-12 months) after stroke. Constrained Spherical Deconvolution-based tractography was performed in the acute and subacute phase to measure Fiber Bundle Capacity (FBC), a quantitative connectivity measure that is valid in crossing fiber regions, in the bilateral dorsal arcuate fasciculus (AF) and the bilateral ventral inferior fronto-occipital fasciculus (IFOF). First, concurrent analyses revealed positive associations between the left AF and phonology, and between the bilateral IFOF and semantics in the acute - but not subacute - phase, supporting the dual-stream language model. Second, neuroplasticity analyses revealed a decrease in connection density of the bilateral AF - but not the IFOF - from the acute to the subacute phase, possibly reflecting post stroke white matter degeneration in areas adjacent to the lesion. Third, predictive analyses revealed no contribution of acute FBC measures to the prediction of later language outcomes over and above the initial language scores, suggesting no added value ofthe diffusion measures for languageprediction. Our study provides new insights on (changes in) connectivity of damaged and undamaged language pathways in patients with aphasia in the first months after stroke, as well as if/how such measures are related to language outcomes at different stages of recovery. Individual results are discussed in the light of current frameworks of language processing and aphasia recovery.
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Affiliation(s)
- Klara Schevenels
- Research Group Experimental Oto-Rhino-Laryngology, Department of Neurosciences, KU Leuven, Onderwijs en Navorsing 2 (O&N2), Herestraat 49 box 721, 3000 Leuven, Belgium,Leuven Brain Institute, KU Leuven, Onderwijs en Navorsing 5 (O&N 5), Herestraat 49 box 1020, 3000 Leuven, Belgium
| | - Robin Gerrits
- Department of Experimental Psychology, Faculty of Psychology and Educational Sciences, Ghent University, Henri Dunantlaan 2, 9000 Ghent, Belgium
| | - Robin Lemmens
- Department of Neurology, University Hospitals Leuven, Herestraat 49, 3000 Leuven, Belgium,Research Group Experimental Neurology, Department of Neurosciences, KU Leuven, Herestraat 49 box 7003, 3000 Leuven, Belgium,Laboratory of Neurobiology, VIB Center for Brain & Disease Research, Onderwijs en Navorsing 5 (O&N 5), Herestraat 49 box 602, 3000 Leuven, Belgium,Leuven Brain Institute, KU Leuven, Onderwijs en Navorsing 5 (O&N 5), Herestraat 49 box 1020, 3000 Leuven, Belgium
| | - Bert De Smedt
- Parenting and Special Education Research Unit, Faculty of Psychology and Educational Sciences, KU Leuven, Leopold Vanderkelenstraat 32 box 3765, 3000 Leuven, Belgium,Leuven Brain Institute, KU Leuven, Onderwijs en Navorsing 5 (O&N 5), Herestraat 49 box 1020, 3000 Leuven, Belgium
| | - Inge Zink
- Research Group Experimental Oto-Rhino-Laryngology, Department of Neurosciences, KU Leuven, Onderwijs en Navorsing 2 (O&N2), Herestraat 49 box 721, 3000 Leuven, Belgium,Leuven Brain Institute, KU Leuven, Onderwijs en Navorsing 5 (O&N 5), Herestraat 49 box 1020, 3000 Leuven, Belgium
| | - Maaike Vandermosten
- Research Group Experimental Oto-Rhino-Laryngology, Department of Neurosciences, KU Leuven, Onderwijs en Navorsing 2 (O&N2), Herestraat 49 box 721, 3000 Leuven, Belgium,Leuven Brain Institute, KU Leuven, Onderwijs en Navorsing 5 (O&N 5), Herestraat 49 box 1020, 3000 Leuven, Belgium,Corresponding author at: Research Group Experimental Oto-Rhino-Laryngology, Department of Neurosciences, KU Leuven, Onderwijs en Navorsing 2 (O&N2), Herestraat 49 box 721, 3000 Leuven, Belgium.
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Couplet Analysis of Linguistic Topology Using Deep Neural Networks in Cognitive Linguistics. COMPUTATIONAL INTELLIGENCE AND NEUROSCIENCE 2022; 2022:9123922. [PMID: 36268161 PMCID: PMC9578848 DOI: 10.1155/2022/9123922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 09/05/2022] [Accepted: 10/03/2022] [Indexed: 11/19/2022]
Abstract
The work reported here primarily aims to realize the automatic generation of couplets using the linguistic topology of deep neural network (DNN). First, the symmetry, topology, and cognitive linguistics of language are explored to lay a theoretical foundation for subsequent model establishment and analysis. Then, the recurrent neural network (RNN) is employed to build the Seq2Seq model, and Liweng's Guide to Rhyme (an ancient Chinese enlightenment reading material to poetry creation) is imported into the Seq2Seq model as a basic corpus. Eventually, the entire system is implemented automatically on TensorFlow. The system undergoes tests of the five-character quatrain, the seven-character quatrain, the couplet, and the part-of-speech detection. Results demonstrate that both the first and the second lines of the couplet present an excellent correspondence regarding sentences and words. After some famous verses are entered, the second line of the couplet obtained is quite vivid and appropriate. Meanwhile, the results can be generated quickly and meet the requirements on rhyme and couplet matching. This model can input verses according to users' own needs and generate the second line of the couplet quickly, showing good correspondence in words, part-of-speech, and sentence pattern. Because the couplet belongs to Chinese traditional culture, it has a strong local Chinese cultural flavor. The system designed based on computer technology can help people learn and experience the charm of couplets.
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Katsuno Y, Ueki Y, Ito K, Murakami S, Aoyama K, Oishi N, Kan H, Matsukawa N, Nagao K, Tatsumi H. Effects of a new speech support application on intensive speech therapy and changes in functional brain connectivity in patients with post-stroke aphasia. Front Hum Neurosci 2022; 16:870733. [PMID: 36211132 PMCID: PMC9535658 DOI: 10.3389/fnhum.2022.870733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 08/29/2022] [Indexed: 11/13/2022] Open
Abstract
Aphasia is a language disorder that occurs after a stroke and impairs listening, speaking, reading, writing, and calculation skills. Patients with post-stroke aphasia in Japan are increasing due to population aging and the advancement of medical treatment. Opportunities for adequate speech therapy in chronic stroke are limited due to time constraints. Recent studies have reported that intensive speech therapy for a short period of time or continuous speech therapy using high-tech equipment, including speech applications (apps, can improve aphasia even in the chronic stage. However, its underlying mechanism for improving language function and its effect on other cognitive functions remains unclear. In the present study, we investigated whether intensive speech therapy using a newly developed speech support app could improve aphasia and other cognitive functions in patients with chronic stroke. Furthermore, we examined whether it can alter the brain network related to language and other cortical areas. Thus, we conducted a prospective, single-comparison study to examine the effects of a new speech support app on language and cognitive functions and used resting state functional MRI (rs-fMRI) regions of interest (ROI) to ROI analysis to determine changes in the related brain network. Two patients with chronic stroke participated in this study. They used the independent speech therapy system to perform eight sets of 20 randomly presented words/time (taking approximately 20 min), for 8 consecutive weeks. Their language, higher cognitive functions including attention function, and rs-fMRI, were evaluated before and after the rehabilitation intervention using the speech support app. Both patients had improved pronunciation, daily conversational situations, and attention. The rs-fMRI analysis showed increased functional connectivity of brain regions associated with language and attention related areas. Our results show that intensive speech therapy using this speech support app can improve language and attention functions even in the chronic stage of stroke, and may be a useful tool for patients with aphasia. In the future, we will conduct longitudinal studies with larger numbers of patients, which we hope will continue the trends seen in the current study, and provide even stronger evidence for the usefulness of this new speech support app.
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Affiliation(s)
- Yuta Katsuno
- Department of Rehabilitation Medicine, Japanese Red Cross Aichi Medical Center Nagoya Daini Hospital, Nagoya, Japan
| | - Yoshino Ueki
- Department of Rehabilitation Medicine, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
- *Correspondence: Yoshino Ueki
| | - Keiichi Ito
- Department of Rehabilitation Medicine, Kamiida Rehabilitation Hospital, Nagoya, Japan
| | - Satona Murakami
- Department of Rehabilitation Medicine, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
- Satona Murakami
| | - Kiminori Aoyama
- Department of Rehabilitation Medicine, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Naoya Oishi
- Medical Innovation Centre, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Hirohito Kan
- Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Noriyuki Matsukawa
- Department of Neurology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Katashi Nagao
- Department of Intelligent Systems, Graduate School of Informatics, Nagoya University, Nagoya, Japan
| | - Hiroshi Tatsumi
- Department of Health Science, Aichi Gakuin University, Nagoya, Japan
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Popova M, Fakhar K, Braun W. ‘One region to control them all'- the surprising effectiveness of network control theory in predicting post-stroke recovery from aphasia. Front Comput Neurosci 2022; 16:943396. [PMID: 36034934 PMCID: PMC9399645 DOI: 10.3389/fncom.2022.943396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 07/26/2022] [Indexed: 12/05/2022] Open
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22
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Varkanitsa M, Kiran S. Understanding, facilitating and predicting aphasia recovery after rehabilitation. INTERNATIONAL JOURNAL OF SPEECH-LANGUAGE PATHOLOGY 2022; 24:248-259. [PMID: 35603543 PMCID: PMC9398975 DOI: 10.1080/17549507.2022.2075036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Purpose: This paper reviews several studies whose aim was to understand the nature of language recovery in chronic aphasia and identify predictors of how people may recover their language functions after a brain injury.Method: Several studies that mostly draw from data collected within the Centre for Neurobiology of Language Recovery were reviewed and categorised in four aspects of language impairment and recovery in aphasia: (a) neural markers for language impairment and recovery, (b) language and cognitive markers for language impairment and recovery, (c) effective treatments and (d) predictive modelling of treatment-induced rehabilitation.Result: Language impairment and recovery in stroke-induced aphasia is multi-factorial, including patient-specific and treatment-specific factors. A combination of these factors may help us predict treatment responsiveness even before treatment begins.Conclusion: Continued work on this topic will lead to a better understanding of the mechanisms that underly language impairment and treatment-induced recovery in aphasia, and, consequently, use this information to predict each person's recovery profile trajectory and provide optimal prescriptions regarding the type and dosage of treatment.
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Affiliation(s)
- Maria Varkanitsa
- Aphasia Research Laboratory, Department of Speech, Language & Hearing Sciences, Sargent College of Health and Rehabilitation Sciences, Boston University, Boston, MA, USA
| | - Swathi Kiran
- Aphasia Research Laboratory, Department of Speech, Language & Hearing Sciences, Sargent College of Health and Rehabilitation Sciences, Boston University, Boston, MA, USA
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Kristinsson S, den Ouden DB, Rorden C, Newman-Norlund R, Neils-Strunjas J, Fridriksson J. Predictors of Therapy Response in Chronic Aphasia: Building a Foundation for Personalized Aphasia Therapy. J Stroke 2022; 24:189-206. [PMID: 35677975 PMCID: PMC9194549 DOI: 10.5853/jos.2022.01102] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 04/21/2022] [Indexed: 11/12/2022] Open
Abstract
Chronic aphasia, a devastating impairment of language, affects up to a third of stroke survivors. Speech and language therapy has consistently been shown to improve language function in prior clinical trials, but few clinicially applicable predictors of individual therapy response have been identified to date. Consequently, clinicians struggle substantially with prognostication in the clinical management of aphasia. A rising prevalence of aphasia, in particular in younger populations, has emphasized the increasing demand for a personalized approach to aphasia therapy, that is, therapy aimed at maximizing language recovery of each individual with reference to evidence-based clinical recommendations. In this narrative review, we discuss the current state of the literature with respect to commonly studied predictors of therapy response in aphasia. In particular, we focus our discussion on biographical, neuropsychological, and neurobiological predictors, and emphasize limitations of the literature, summarize consistent findings, and consider how the research field can better support the development of personalized aphasia therapy. In conclusion, a review of the literature indicates that future research efforts should aim to recruit larger samples of people with aphasia, including by establishing multisite aphasia research centers.
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Affiliation(s)
- Sigfus Kristinsson
- Center for the Study of Aphasia Recovery, University of South Carolina, Columbia, SC, USA
- Department of Communication Sciences and Disorders, University of South Carolina, Columbia, SC, USA
- Correspondence: Sigfus Kristinsson Department of Communication Sciences and Disorders, University of South Carolina, 915 Greene Street, Columbia, SC 29209, USA Tel: +1-803-553-4689 Fax: +1-803-777-9547 E-mail:
| | - Dirk B. den Ouden
- Center for the Study of Aphasia Recovery, University of South Carolina, Columbia, SC, USA
- Department of Communication Sciences and Disorders, University of South Carolina, Columbia, SC, USA
| | - Chris Rorden
- Center for the Study of Aphasia Recovery, University of South Carolina, Columbia, SC, USA
- Department of Psychology, University of South Carolina, Columbia, SC, USA
| | - Roger Newman-Norlund
- Center for the Study of Aphasia Recovery, University of South Carolina, Columbia, SC, USA
- Department of Psychology, University of South Carolina, Columbia, SC, USA
| | - Jean Neils-Strunjas
- Department of Communication Sciences and Disorders, University of South Carolina, Columbia, SC, USA
| | - Julius Fridriksson
- Center for the Study of Aphasia Recovery, University of South Carolina, Columbia, SC, USA
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24
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Adezati E, Thye M, Edmondson-Stait AJ, Szaflarski JP, Mirman D. Lesion correlates of auditory sentence comprehension deficits in post-stroke aphasia. NEUROIMAGE. REPORTS 2022; 2:None. [PMID: 35243477 PMCID: PMC8843825 DOI: 10.1016/j.ynirp.2021.100076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 12/27/2021] [Accepted: 12/28/2021] [Indexed: 11/19/2022]
Abstract
Auditory sentence comprehension requires coordination of multiple levels of processing: auditory-phonological perception, lexical-semantic comprehension, syntactic parsing and discourse construction, as well as executive functions such as verbal working memory (WM) and cognitive control. This study examined the lesion correlates of sentence comprehension deficits in post-stroke aphasia, building on prior work on this topic by using a different and clinically-relevant measure of sentence comprehension (the Token Test) and multivariate (SCCAN) and connectome-based lesion-symptom mapping methods. The key findings were that lesions in the posterior superior temporal lobe and inferior frontal gyrus (pars triangularis) were associated with sentence comprehension deficits, which was observed in both mass univariate and multivariate lesion-symptom mapping. Graph theoretic measures of connectome disruption were not statistically significantly associated with sentence comprehension deficits after accounting for overall lesion size.
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Affiliation(s)
- Erica Adezati
- Department of Psychology, University of Edinburgh, Edinburgh, UK
| | - Melissa Thye
- Department of Psychology, University of Edinburgh, Edinburgh, UK
| | | | - Jerzy P. Szaflarski
- Department of Neurology and the University of Alabama at Birmingham Epilepsy Center, University of Alabama at Birmingham Heersink School of Medicine, Birmingham, AL, USA
| | - Daniel Mirman
- Department of Psychology, University of Edinburgh, Edinburgh, UK
- Corresponding author.
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25
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Li R, Mukadam N, Kiran S. Functional MRI evidence for reorganization of language networks after stroke. HANDBOOK OF CLINICAL NEUROLOGY 2022; 185:131-150. [PMID: 35078595 DOI: 10.1016/b978-0-12-823384-9.00007-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
In this chapter, we review fMRI evidence for language reorganization in individuals with poststroke aphasia. Several studies in the current literature have utilized fMRI as a tool to understand patterns of functional reorganization in poststroke aphasia. Consistent with previous models that have been proposed to explain the trajectory of language recovery, differential patterns of language processing and language recovery have been identified across individuals with poststroke aphasia in different stages of recovery. Overall, a global network breakdown typically occurs in the early stages of aphasia recovery, followed by normalization in "traditional" left hemisphere language networks. Depending on individual characteristics, right hemisphere regions and bilateral domain-general regions may be further recruited. The main takeaway of this chapter is that poststroke aphasia recovery does not depend on individual neural regions, but rather involves a complex interaction among regions in larger networks. Many of the unresolved issues and contrastive findings in the literature warrant further research with larger groups of participants and standard protocols of fMRI implementation.
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Affiliation(s)
- Ran Li
- Department of Speech, Language and Hearing Sciences, Boston University, Boston, MA, United States
| | - Nishaat Mukadam
- Department of Speech, Language and Hearing Sciences, Boston University, Boston, MA, United States
| | - Swathi Kiran
- Department of Speech, Language and Hearing Sciences, Boston University, Boston, MA, United States.
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26
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Billot A, Lai S, Varkanitsa M, Braun EJ, Rapp B, Parrish TB, Higgins J, Kurani AS, Caplan D, Thompson CK, Ishwar P, Betke M, Kiran S. Multimodal Neural and Behavioral Data Predict Response to Rehabilitation in Chronic Poststroke Aphasia. Stroke 2022; 53:1606-1614. [PMID: 35078348 PMCID: PMC9022691 DOI: 10.1161/strokeaha.121.036749] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Poststroke recovery depends on multiple factors and varies greatly across individuals. Using machine learning models, this study investigated the independent and complementary prognostic role of different patient-related factors in predicting response to language rehabilitation after a stroke. METHODS Fifty-five individuals with chronic poststroke aphasia underwent a battery of standardized assessments and structural and functional magnetic resonance imaging scans, and received 12 weeks of language treatment. Support vector machine and random forest models were constructed to predict responsiveness to treatment using pretreatment behavioral, demographic, and structural and functional neuroimaging data. RESULTS The best prediction performance was achieved by a support vector machine model trained on aphasia severity, demographics, measures of anatomic integrity and resting-state functional connectivity (F1=0.94). This model resulted in a significantly superior prediction performance compared with support vector machine models trained on all feature sets (F1=0.82, P<0.001) or a single feature set (F1 range=0.68-0.84, P<0.001). Across random forest models, training on resting-state functional magnetic resonance imaging connectivity data yielded the best F1 score (F1=0.87). CONCLUSIONS While behavioral, multimodal neuroimaging data and demographic information carry complementary information in predicting response to rehabilitation in chronic poststroke aphasia, functional connectivity of the brain at rest after stroke is a particularly important predictor of responsiveness to treatment, both alone and combined with other patient-related factors.
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Affiliation(s)
- Anne Billot
- Sargent College of Health and Rehabilitation Sciences (A.B., M.V., E.J.B., S.K.), Boston University, MA
- School of Medicine (A.B.), Boston University, MA
| | - Sha Lai
- Department of Computer Science (S.L., P.I., M.B.), Boston University, MA
| | - Maria Varkanitsa
- Sargent College of Health and Rehabilitation Sciences (A.B., M.V., E.J.B., S.K.), Boston University, MA
| | - Emily J. Braun
- Sargent College of Health and Rehabilitation Sciences (A.B., M.V., E.J.B., S.K.), Boston University, MA
| | - Brenda Rapp
- Department of Cognitive Science, Johns Hopkins University, Baltimore, MD (B.R.)
| | - Todd B. Parrish
- Department of Radiology (T.B.P., J.H.), Northwestern University, Chicago, IL
| | - James Higgins
- Department of Radiology (T.B.P., J.H.), Northwestern University, Chicago, IL
| | - Ajay S. Kurani
- Department of Neurology (A.S.K.), Northwestern University, Chicago, IL
| | - David Caplan
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston (D.C.)
| | - Cynthia K. Thompson
- Feinberg School of Medicine and Department of Communication Sciences and Disorders (C.K.T.), Northwestern University, Chicago, IL
| | - Prakash Ishwar
- Department of Computer Science (S.L., P.I., M.B.), Boston University, MA
| | - Margrit Betke
- Department of Computer Science (S.L., P.I., M.B.), Boston University, MA
| | - Swathi Kiran
- Sargent College of Health and Rehabilitation Sciences (A.B., M.V., E.J.B., S.K.), Boston University, MA
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27
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Masson-Trottier M, Sontheimer A, Durand E, Ansaldo AI. Resting-State Functional Connectivity following Phonological Component Analysis: The Combined Action of Phonology and Visual Orthographic Cues. Brain Sci 2021; 11:1458. [PMID: 34827457 PMCID: PMC8615968 DOI: 10.3390/brainsci11111458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/22/2021] [Accepted: 10/26/2021] [Indexed: 11/16/2022] Open
Abstract
Anomia is the most frequent and pervasive symptom for people with aphasia (PWA). Phonological component analysis (PCA) is a therapy incorporating phonological cues to treat anomia. Investigations of neural correlates supporting improvements following PCA remain scarce. Resting-state functional connectivity (rsFC) as a marker of therapy-induced neuroplasticity has been reported by our team. The present study explores the efficacy of PCA in French and associated therapy-induced neuroplasticity using whole-brain rsFC analysis. Ten PWA participated in a pre-/post-PCA fMRI study with cognitive linguistic assessments. PCA was delivered in French following the standard procedure. PCA led to significant improvement with trained and untrained items. PCA also led to changes in rsFC between distributed ROIs in the semantic network, visual network, and sub-cortical areas. Changes in rsFC can be interpreted within the frame of the visual and phonological nature of PCA. Behavioral and rsFC data changes associated with PCA in French highlight its efficacy and point to the importance of phonological and orthographic cues to consolidate the word-retrieval strategy, contributing to generalization to untrained words.
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Affiliation(s)
- Michèle Masson-Trottier
- Centre de Recherche de l’Institut Universitaire de Gériatrie de Montréal, Montréal, QC H3W 1W5, Canada;
- Faculté de Médecine, Université de Montréal, Montréal, QC H3T 1J4, Canada
| | - Anna Sontheimer
- Centre National de la Recherche Scientifique, Institut National Polytechnique-Clermont, Institut Pascal, Université Clermont Auvergne, F-63000 Clermont-Ferrand, France;
- Centre Hospitalier Universitaire de Clermont-Ferrand, F-63000 Clermont-Ferrand, France
| | - Edith Durand
- U.F.R. Lettres, Cultures et Sciences Humaines, Université Clermont Auvergne, F-63000 Clermont-Ferrand, France;
| | - Ana Inés Ansaldo
- Centre de Recherche de l’Institut Universitaire de Gériatrie de Montréal, Montréal, QC H3W 1W5, Canada;
- Faculté de Médecine, Université de Montréal, Montréal, QC H3T 1J4, Canada
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28
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Truzman T, Rochon E, Meltzer J, Leonard C, Bitan T. Simultaneous Normalization and Compensatory Changes in Right Hemisphere Connectivity during Aphasia Therapy. Brain Sci 2021; 11:1330. [PMID: 34679395 PMCID: PMC8534113 DOI: 10.3390/brainsci11101330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/01/2021] [Accepted: 10/03/2021] [Indexed: 11/17/2022] Open
Abstract
Changes in brain connectivity during language therapy were examined among participants with aphasia (PWA), aiming to shed light on neural reorganization in the language network. Four PWA with anomia following left hemisphere stroke and eight healthy controls (HC) participated in the study. Two fMRI scans were administered to all participants with a 3.5-month interval. The fMRI scans included phonological and semantic tasks, each consisting of linguistic and perceptual matching conditions. Between the two fMRI scans, PWA underwent Phonological Components Analysis treatment. Changes in effective connectivity during the treatment were examined within right hemisphere (RH) architecture. The results illustrate that following the treatment, the averaged connectivity of PWA across all perceptual and linguistic conditions in both tasks increased resemblance to HC, reflecting the normalization of neural processes associated with silent object name retrieval. In contrast, connections that were specifically enhanced by the phonological condition in PWA decreased in their resemblance to HC, reflecting emerging compensatory reorganization in RH connectivity to support phonological processing. These findings suggest that both normalization and compensation play a role in neural language reorganization at the chronic stage, occurring simultaneously in the same brain.
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Affiliation(s)
- Tammar Truzman
- Communication Sciences and Disorders Department and IIPDM, University of Haifa, Haifa 3498838, Israel
- The Integrated Brain and Behavior Research Center, University of Haifa, Haifa 3498838, Israel
| | - Elizabeth Rochon
- Department of Speech Language Pathology and Rehabilitation Sciences Institute, University of Toronto, Toronto, ON M5G 1V7, Canada; (E.R.); (J.M.); (C.L.); (T.B.)
- KITE Research Institute, Toronto Rehab, University Health Network (UHN), Toronto, ON M5G 2A2, Canada
| | - Jed Meltzer
- Department of Speech Language Pathology and Rehabilitation Sciences Institute, University of Toronto, Toronto, ON M5G 1V7, Canada; (E.R.); (J.M.); (C.L.); (T.B.)
- Psychology Department, University of Toronto, Toronto, ON M5S 1A1, Canada
- Rotman Research Institute, Baycrest Health Sciences, Toronto, ON M6A 2E1, Canada
| | - Carol Leonard
- Department of Speech Language Pathology and Rehabilitation Sciences Institute, University of Toronto, Toronto, ON M5G 1V7, Canada; (E.R.); (J.M.); (C.L.); (T.B.)
- School of Rehabilitation Sciences, University of Ottawa, Ottawa, ON K1H 8L1, Canada
| | - Tali Bitan
- The Integrated Brain and Behavior Research Center, University of Haifa, Haifa 3498838, Israel
- Department of Speech Language Pathology and Rehabilitation Sciences Institute, University of Toronto, Toronto, ON M5G 1V7, Canada; (E.R.); (J.M.); (C.L.); (T.B.)
- Psychology Department and IIPDM, University of Haifa, Haifa 3498838, Israel
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29
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Gilmore N, Yücel MA, Li X, Boas DA, Kiran S. Investigating Language and Domain-General Processing in Neurotypicals and Individuals With Aphasia - A Functional Near-Infrared Spectroscopy Pilot Study. Front Hum Neurosci 2021; 15:728151. [PMID: 34602997 PMCID: PMC8484538 DOI: 10.3389/fnhum.2021.728151] [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: 06/21/2021] [Accepted: 08/25/2021] [Indexed: 11/29/2022] Open
Abstract
Brain reorganization patterns associated with language recovery after stroke have long been debated. Studying mechanisms of spontaneous and treatment-induced language recovery in post-stroke aphasia requires a network-based approach given the potential for recruitment of perilesional left hemisphere language regions, homologous right hemisphere language regions, and/or spared bilateral domain-general regions. Recent hardware, software, and methodological advances in functional near-infrared spectroscopy (fNIRS) make it well-suited to examine this question. fNIRS is cost-effective with minimal contraindications, making it a robust option to monitor treatment-related brain activation changes over time. Establishing clear activation patterns in neurotypical adults during language and domain-general cognitive processes via fNIRS is an important first step. Some fNIRS studies have investigated key language processes in healthy adults, yet findings are challenging to interpret in the context of methodological limitations. This pilot study used fNIRS to capture brain activation during language and domain-general processing in neurotypicals and individuals with aphasia. These findings will serve as a reference when interpreting treatment-related changes in brain activation patterns in post-stroke aphasia in the future. Twenty-four young healthy controls, seventeen older healthy controls, and six individuals with left hemisphere stroke-induced aphasia completed two language tasks (i.e., semantic feature, picture naming) and one domain-general cognitive task (i.e., arithmetic) twice during fNIRS. The probe covered bilateral frontal, parietal, and temporal lobes and included short-separation detectors for scalp signal nuisance regression. Younger and older healthy controls activated core language regions during semantic feature processing (e.g., left inferior frontal gyrus pars opercularis) and lexical retrieval (e.g., left inferior frontal gyrus pars triangularis) and domain-general regions (e.g., bilateral middle frontal gyri) during hard versus easy arithmetic as expected. Consistent with theories of post-stroke language recovery, individuals with aphasia activated areas outside the traditional networks: left superior frontal gyrus and left supramarginal gyrus during semantic feature judgment; left superior frontal gyrus and right precentral gyrus during picture naming; and left inferior frontal gyrus pars opercularis during arithmetic processing. The preliminary findings in the stroke group highlight the utility of using fNIRS to study language and domain-general processing in aphasia.
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Affiliation(s)
- Natalie Gilmore
- Department of Speech Language & Hearing Sciences, Sargent College of Health and Rehabilitation Sciences, Boston University, Boston, MA, United States
| | - Meryem Ayse Yücel
- Neurophotonics Center, Biomedical Engineering, Boston University, Boston, MA, United States
| | - Xinge Li
- Neurophotonics Center, Biomedical Engineering, Boston University, Boston, MA, United States.,Department of Psychology, College of Liberal Arts and Social Sciences, University of Houston, Houston, TX, United States
| | - David A Boas
- Neurophotonics Center, Biomedical Engineering, Boston University, Boston, MA, United States
| | - Swathi Kiran
- Department of Speech Language & Hearing Sciences, Sargent College of Health and Rehabilitation Sciences, Boston University, Boston, MA, United States
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30
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Sihvonen AJ, Ripollés P, Leo V, Saunavaara J, Parkkola R, Rodríguez-Fornells A, Soinila S, Särkämö T. Vocal music listening enhances post-stroke language network reorganization. eNeuro 2021; 8:ENEURO.0158-21.2021. [PMID: 34140351 PMCID: PMC8266215 DOI: 10.1523/eneuro.0158-21.2021] [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: 04/13/2021] [Revised: 05/24/2021] [Accepted: 06/06/2021] [Indexed: 11/25/2022] Open
Abstract
Listening to vocal music has been recently shown to improve language recovery in stroke survivors. The neuroplasticity mechanisms supporting this effect are, however, still unknown. Using data from a three-arm single-blind randomized controlled trial including acute stroke patients (N=38) and a 3-month follow-up, we set out to compare the neuroplasticity effects of daily listening to self-selected vocal music, instrumental music, and audiobooks on both brain activity and structural connectivity of the language network. Using deterministic tractography we show that the 3-month intervention induced an enhancement of the microstructural properties of the left frontal aslant tract (FAT) for the vocal music group as compared to the audiobook group. Importantly, this increase in the strength of the structural connectivity of the left FAT correlated with improved language skills. Analyses of stimulus-specific activation changes showed that the vocal music group exhibited increased activations in the frontal termination points of the left FAT during vocal music listening as compared to the audiobook group from acute to 3-month post-stroke stage. The increased activity correlated with the structural neuroplasticity changes in the left FAT. These results suggest that the beneficial effects of vocal music listening on post-stroke language recovery are underpinned by structural neuroplasticity changes within the language network and extend our understanding of music-based interventions in stroke rehabilitation.Significance statementPost-stroke language deficits have a devastating effect on patients and their families. Current treatments yield highly variable outcomes and the evidence for their long-term effects is limited. Patients often receive insufficient treatment that are predominantly given outside the optimal time window for brain plasticity. Post-stroke vocal music listening improves language outcome which is underpinned by neuroplasticity changes within the language network. Vocal music listening provides a complementary rehabilitation strategy which could be safely implemented in the early stages of stroke rehabilitation and seems to specifically target language symptoms and recovering language network.
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Affiliation(s)
- Aleksi J Sihvonen
- Cognitive Brain Research Unit, Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Finland
- Centre for Clinical Research, The University of Queensland, Australia
| | - Pablo Ripollés
- Department of Psychology, New York University, USA
- Music and Audio Research Laboratory, New York University, USA
- Center for Language Music and emotion, New York UniversityUSA
| | - Vera Leo
- Cognitive Brain Research Unit, Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Finland
| | - Jani Saunavaara
- Department of Medical Physics, Turku University Hospital, Turku, Finland
| | - Riitta Parkkola
- Department of Radiology, Turku University Hospital and University of Turku, Finland
| | - Antoni Rodríguez-Fornells
- Department of Cognition, Development and Education Psychology, University of Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain
- Division of Clinical Neurosciences, Department of Neurology, Turku University Hospital and University of Turku, Finland
| | - Seppo Soinila
- Division of Clinical Neurosciences, Department of Neurology, Turku University Hospital and University of Turku, Finland
| | - Teppo Särkämö
- Cognitive Brain Research Unit, Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Finland
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31
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Vitti E, Hillis AE. Treatment of post-stroke aphasia: A narrative review for stroke neurologists. Int J Stroke 2021; 16:1002-1008. [PMID: 33949274 DOI: 10.1177/17474930211017807] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This review is intended to help physicians guide patients to optimal management of post-stroke aphasia. We review literature on post-stroke aphasia treatment, focusing on: (1) when and for whom language therapy is most effective, (2) the variety of approaches that can be effective for different individuals, and (3) the extent to which behavioral therapy might be augmented by non-invasive brain stimulation and/or medications.
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Affiliation(s)
- Emilia Vitti
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Argye E Hillis
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, USA
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32
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Fridriksson J, Hillis AE. Current Approaches to the Treatment of Post-Stroke Aphasia. J Stroke 2021; 23:183-201. [PMID: 34102754 PMCID: PMC8189855 DOI: 10.5853/jos.2020.05015] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 02/21/2021] [Accepted: 04/30/2021] [Indexed: 12/16/2022] Open
Abstract
Aphasia, impairment of language after stroke or other neurological insult, is a common and often devastating condition that affects nearly every social activity and interaction. Behavioral speech and language therapy is the mainstay of treatment, although other interventions have been introduced to augment the effects of the behavioral therapy. In this narrative review, we discuss advances in aphasia therapy in the last 5 years and focus primarily on properly powered, randomized, controlled trials of both behavioral therapies and interventions to augment therapy for post-stroke aphasia. These trials include evaluation of behavioral therapies and computer-delivered language therapies. We also discuss outcome prediction trials as well as interventional trials that have employed noninvasive brain stimulation, or medications to augment language therapy. Supported by evidence from Phase III trials and large meta-analyses, it is now generally accepted that aphasia therapy can improve language processing for many patients. Not all patients respond similarly to aphasia therapy with the most severe patients being the least likely responders. Nevertheless, it is imperative that all patients, regardless of severity, receive aphasia management focused on direct therapy of language deficits, counseling, or both. Emerging evidence from Phase II trials suggests transcranial brain stimulation is a promising method to boost aphasia therapy outcomes.
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Affiliation(s)
- Julius Fridriksson
- Department of Communication Sciences and Disorders, University of South Carolina, Columbia, SC, USA
| | - Argye Elizabeth Hillis
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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33
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Cherney LR, Babbitt EM, Wang X, Pitts LL. Extended fMRI-Guided Anodal and Cathodal Transcranial Direct Current Stimulation Targeting Perilesional Areas in Post-Stroke Aphasia: A Pilot Randomized Clinical Trial. Brain Sci 2021; 11:306. [PMID: 33671031 PMCID: PMC7997197 DOI: 10.3390/brainsci11030306] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 02/22/2021] [Accepted: 02/25/2021] [Indexed: 11/17/2022] Open
Abstract
Transcranial direct current stimulation (tDCS) may enhance speech and language treatment (SLT) for stroke survivors with aphasia; however, to date, there is no standard protocol for the application of tDCS in post-stroke aphasia. We explored the safety and efficacy of fMRI-guided tDCS on functional language and cortical activity when delivered to the lesioned left hemisphere concurrently with SLT across an extended, six-week treatment period. Twelve persons with chronic, nonfluent aphasia following a single left-hemisphere stroke participated in the three-arm (anodal vs. cathodal vs. sham) single-blind, parallel, pilot trial. No serious adverse events occurred during 30 treatment sessions or in the following six weeks. All groups demonstrated functional language gains following intensive treatment; however, active tDCS resulted in greater gains in standardized, probe, and caregiver-reported measures of functional language than sham. Evidence declaring one polarity as superior for inducing language recovery was mixed. However, cathodal stimulation to the lesioned left hemisphere, expected to have a down-regulating effect, resulted in increased areas of cortical activation across both hemispheres, and specifically perilesionally. Generalization of these preliminary findings is limited; however, results are nevertheless compelling that tDCS combined with SLT can be safely applied across extended durations, with the potential to enhance functional language and cortical activation for persons with aphasia.
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Affiliation(s)
- Leora R. Cherney
- Think + Speak Lab, Shirley Ryan AbilityLab, Chicago, IL 60611, USA; (E.M.B.); (L.L.P.)
- Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Department of Communication Sciences and Disorders, Northwestern University, Evanston, IL 60208, USA
| | - Edna M. Babbitt
- Think + Speak Lab, Shirley Ryan AbilityLab, Chicago, IL 60611, USA; (E.M.B.); (L.L.P.)
- Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Xue Wang
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA;
| | - Laura L. Pitts
- Think + Speak Lab, Shirley Ryan AbilityLab, Chicago, IL 60611, USA; (E.M.B.); (L.L.P.)
- Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Department of Communication Sciences and Disorders, University of Northern Iowa, Cedar Falls, IA 50614, USA
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34
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Cherney LR, Lee JB, Kim KYA, van Vuuren S. Web-based Oral Reading for Language in Aphasia (Web ORLA ®): A pilot randomized control trial. Clin Rehabil 2021; 35:976-987. [PMID: 33472420 DOI: 10.1177/0269215520988475] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE To investigate an intensive asynchronous computer-based treatment delivered remotely with clinician oversight to people with aphasia. DESIGN Single-blind, randomized placebo-controlled trial. SETTING Free-standing urban rehabilitation hospital. PARTICIPANTS Adults with aphasia (at least six months post-onset). INTERVENTIONS Experimental treatment was Web ORLA® (Oral Reading for Language in Aphasia) which provides repeated choral and independent reading aloud of sentences with a virtual therapist. Placebo was a commercially available computer game. Participants were instructed to practice 90 minutes/day, six days/week for six weeks. MAIN MEASURES Change in Language Quotient of the Western Aphasia Battery-Revised from pre-treatment to post-treatment and pre-treatment to six weeks following the end of treatment. RESULTS 32 participants (19 Web ORLA®, 13 Control) completed the intervention and post-treatment assessment; 27 participants (16 Web ORLA®, 11 Control) completed the follow-up assessment six weeks after treatment had ended. Web ORLA® treatment resulted in significant improvements in language performance from pre-treatment to immediately post-treatment (X = 2.96; SD = 4.32; P < 0.01; ES = 0.68) and from pre-treatment to six weeks following the end of treatment (X = 4.53; SD = 3.16; P < 0.001; ES = 1.43). There was no significant difference in the gain from pre-treatment to post-treatment for the Web ORLA® versus Control groups. However, the Web ORLA® group showed significantly greater gains at the six-week follow-up than the control group (X = 2.70; SD = 1.01; P = 0.013; ES = 1.92). CONCLUSION Results provide evidence for improved language outcomes following intensive, web-based delivery of ORLA® to individuals with chronic aphasia. Findings underscore the value of combining clinician oversight with the flexibility of asynchronous practice.
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Affiliation(s)
- Leora R Cherney
- Think and Speak Lab, Shirley Ryan AbilityLab, Chicago, IL, USA.,Departments of Physical Medicine and Rehabilitation and Communication Sciences and Disorders, Northwestern University, Chicago, IL, USA
| | - Jaime B Lee
- Department of Communication Sciences and Disorders, James Madison University, Harrisonburg, VA, USA
| | - Kwang-Youn A Kim
- Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Sarel van Vuuren
- Institute of Cognitive Science, University of Colorado Boulder, Boulder, CO, USA
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Ivanova MV, Herron TJ, Dronkers NF, Baldo JV. An empirical comparison of univariate versus multivariate methods for the analysis of brain-behavior mapping. Hum Brain Mapp 2020; 42:1070-1101. [PMID: 33216425 PMCID: PMC7856656 DOI: 10.1002/hbm.25278] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 10/14/2020] [Accepted: 10/29/2020] [Indexed: 02/06/2023] Open
Abstract
Lesion symptom mapping (LSM) tools are used on brain injury data to identify the neural structures critical for a given behavior or symptom. Univariate lesion symptom mapping (ULSM) methods provide statistical comparisons of behavioral test scores in patients with and without a lesion on a voxel by voxel basis. More recently, multivariate lesion symptom mapping (MLSM) methods have been developed that consider the effects of all lesioned voxels in one model simultaneously. In the current study, we provide a much-needed systematic comparison of several ULSM and MLSM methods, using both synthetic and real data to identify the potential strengths and weaknesses of both approaches. We tested the spatial precision of each LSM method for both single and dual (network type) anatomical target simulations across anatomical target location, sample size, noise level, and lesion smoothing. Additionally, we performed false positive simulations to identify the characteristics associated with each method's spurious findings. Simulations showed no clear superiority of either ULSM or MLSM methods overall, but rather highlighted specific advantages of different methods. No single method produced a thresholded LSM map that exclusively delineated brain regions associated with the target behavior. Thus, different LSM methods are indicated, depending on the particular study design, specific hypotheses, and sample size. Overall, we recommend the use of both ULSM and MLSM methods in tandem to enhance confidence in the results: Brain foci identified as significant across both types of methods are unlikely to be spurious and can be confidently reported as robust results.
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Affiliation(s)
- Maria V Ivanova
- University of California, Berkeley, California, USA.,VA Northern California Health Care System, Martinez, California, USA
| | - Timothy J Herron
- VA Northern California Health Care System, Martinez, California, USA
| | - Nina F Dronkers
- University of California, Berkeley, California, USA.,VA Northern California Health Care System, Martinez, California, USA.,University of California, Davis, California, USA
| | - Juliana V Baldo
- VA Northern California Health Care System, Martinez, California, USA
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Kiran S. Introduction to the 2018 Research Symposium Forum. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2019; 62:3905-3906. [PMID: 31756157 PMCID: PMC7203522 DOI: 10.1044/2019_jslhr-19-00297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 10/22/2019] [Indexed: 06/10/2023]
Abstract
Purpose The purpose of this introduction is to provide an overview of the articles contained within this forum of Journal of Speech, Language, and Hearing Research (JSLHR). Each of these articles is based upon presentations from the Research Symposium at the 2018 annual convention of the American Speech-Language-Hearing Association held in Boston, MA.
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Affiliation(s)
- Swathi Kiran
- Sargent College of Health and Rehabilitation Sciences, Boston University, MA
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