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Papageorgiou G, Kasselimis D, Laskaris N, Potagas C. Unraveling the Thread of Aphasia Rehabilitation: A Translational Cognitive Perspective. Biomedicines 2023; 11:2856. [PMID: 37893229 PMCID: PMC10604624 DOI: 10.3390/biomedicines11102856] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 10/07/2023] [Accepted: 10/09/2023] [Indexed: 10/29/2023] Open
Abstract
Translational neuroscience is a multidisciplinary field that aims to bridge the gap between basic science and clinical practice. Regarding aphasia rehabilitation, there are still several unresolved issues related to the neural mechanisms that optimize language treatment. Although there are studies providing indications toward a translational approach to the remediation of acquired language disorders, the incorporation of fundamental neuroplasticity principles into this field is still in progress. From that aspect, in this narrative review, we discuss some key neuroplasticity principles, which have been elucidated through animal studies and which could eventually be applied in the context of aphasia treatment. This translational approach could be further strengthened by the implementation of intervention strategies that incorporate the idea that language is supported by domain-general mechanisms, which highlights the impact of non-linguistic factors in post-stroke language recovery. Here, we highlight that translational research in aphasia has the potential to advance our knowledge of brain-language relationships. We further argue that advances in this field could lead to improvement in the remediation of acquired language disturbances by remodeling the rationale of aphasia-therapy approaches. Arguably, the complex anatomy and phenomenology of aphasia dictate the need for a multidisciplinary approach with one of its main pillars being translational research.
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Affiliation(s)
- Georgios Papageorgiou
- Neuropsychology and Language Disorders Unit, 1st Department of Neurology, Eginition Hospital, National and Kapodistrian University of Athens, 11528 Athens, Greece
| | - Dimitrios Kasselimis
- Neuropsychology and Language Disorders Unit, 1st Department of Neurology, Eginition Hospital, National and Kapodistrian University of Athens, 11528 Athens, Greece
- Department of Psychology, Panteion University of Social and Political Sciences, 17671 Athens, Greece
| | - Nikolaos Laskaris
- Neuropsychology and Language Disorders Unit, 1st Department of Neurology, Eginition Hospital, National and Kapodistrian University of Athens, 11528 Athens, Greece
- Department of Industrial Design and Production Engineering, School of Engineering, University of West Attica, 12241 Athens, Greece
| | - Constantin Potagas
- Neuropsychology and Language Disorders Unit, 1st Department of Neurology, Eginition Hospital, National and Kapodistrian University of Athens, 11528 Athens, Greece
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Zhou Y, Du X, Xiao J, Cao Y, Guo Q, Zhou A, Zhou J, Li N, Wang Y, Jiao L. A physician survey of poststroke aphasia diagnosis and treatment in China: SPEECH study. Medicine (Baltimore) 2021; 100:e25833. [PMID: 34087826 PMCID: PMC8183701 DOI: 10.1097/md.0000000000025833] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 04/16/2021] [Indexed: 01/04/2023] Open
Abstract
The current status of the diagnosis and management of poststroke aphasia (PSA) in China is unknown.To analyze the physicians' strategy and knowledge about the management of PSA in clinical practice and the needs for standardization of diagnosis and treatment.This survey was conducted in March-August 2019 at 32 tertiary hospitals in 16 provinces/municipalities in China. The attending physicians from the Neurology and Neuro-rehabilitation/Rehabilitation Departments were included. The online questionnaire inquired about patient information, physicians' diagnosis and treatment behavior for PSA, and physicians' understanding of PSA.A total of 236 physicians completed the survey. Regarding PSA assessment, 99.2% of the physicians reported using medical history and physical examination, 93.2% reported using neuroimaging, and 76.3% reported using dedicated scales. Most physicians used a combination of drug and non-drug treatment. Neuro-regenerators/cerebral activators and anti-dementia drugs were the most common pharmacotherapies; butylphthalide, edaravone, and memantine were most frequently prescribed. Six months poststroke was rendered as a spontaneous language recovery period, and a ≥6-month treatment for PSA was suggested by many physicians. The lack of standardized treatment regimen/clinical guidelines and the limited number of approved drugs for PSA were the primary challenges encountered by physicians during practice. The majority of the physicians agreed with the necessity of guidelines or consensus for the diagnosis and treatment of PSA.The knowledge gaps exist among physicians in China regarding the assessment and management of PSA. The improved awareness of the available guidelines/consensus could improve the performance of the physicians.
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Affiliation(s)
- Yuying Zhou
- Department of Neurology, Huanhu Hospital, Tianjin
| | - Xiaoxia Du
- Department of Neurorehabilitation, School of Rehabilitation Medicine, Capital Medical University, Beijing Bo’Ai Hospital, China Rehabilitation Research Center, Beijing
| | - Jun Xiao
- Department of Neurology, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu, Sichuan Province, PR
| | - Yunpeng Cao
- Department of Neurology, First Affiliated Hospital of China Medical University, Shenyang, Liaoning Province
| | - Qihao Guo
- Department of Gerontology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai
| | - Aihong Zhou
- Innovation Center for Neurological Disorders and Department of Neurology, Xuanwu Hospital, Capital Medical University, National Clinical Research Center for Geriatric Diseases, Beijing
| | - Jiong Zhou
- Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou
| | - Nan Li
- Research Center of Clinical Epidemiology, Peking University Third Hospital
| | - Yinhua Wang
- Department of Neurology, the First Hospital of Peking University
| | - Lifei Jiao
- Drug Development Organization, Lundbeck China, Beijing, China
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Schevenels K, Price CJ, Zink I, De Smedt B, Vandermosten M. A Review on Treatment-Related Brain Changes in Aphasia. NEUROBIOLOGY OF LANGUAGE (CAMBRIDGE, MASS.) 2020; 1:402-433. [PMID: 37215585 PMCID: PMC10158631 DOI: 10.1162/nol_a_00019] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 06/29/2020] [Indexed: 05/24/2023]
Abstract
Numerous studies have investigated brain changes associated with interventions targeting a range of language problems in patients with aphasia. We strive to integrate the results of these studies to examine (1) whether the focus of the intervention (i.e., phonology, semantics, orthography, syntax, or rhythmic-melodic) determines in which brain regions changes occur; and (2a) whether the most consistent changes occur within the language network or outside, and (2b) whether these are related to individual differences in language outcomes. The results of 32 studies with 204 unique patients were considered. Concerning (1), the location of treatment-related changes does not clearly depend on the type of language processing targeted. However, there is some support that rhythmic-melodic training has more impact on the right hemisphere than linguistic training. Concerning (2), we observed that language recovery is not only associated with changes in traditional language-related structures in the left hemisphere and homolog regions in the right hemisphere, but also with more medial and subcortical changes (e.g., precuneus and basal ganglia). Although it is difficult to draw strong conclusions, because there is a lack of systematic large-scale studies on this topic, this review highlights the need for an integrated approach to investigate how language interventions impact on the brain. Future studies need to focus on larger samples preserving subject-specific information (e.g., lesion effects) to cope with the inherent heterogeneity of stroke-induced aphasia. In addition, recovery-related changes in whole-brain connectivity patterns need more investigation to provide a comprehensive neural account of treatment-related brain plasticity and language recovery.
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Affiliation(s)
- Klara Schevenels
- Experimental Oto-Rhino-Laryngology, Department of Neurosciences, KU Leuven, Leuven, Belgium
| | - Cathy J. Price
- Welcome Centre for Human Neuroimaging, Institute of Neurology, University College London, UK
| | - Inge Zink
- Experimental Oto-Rhino-Laryngology, Department of Neurosciences, KU Leuven, Leuven, Belgium
| | - Bert De Smedt
- Parenting and Special Education Research Unit, Faculty of Psychology and Educational Sciences, KU Leuven, Leuven, Belgium
| | - Maaike Vandermosten
- Experimental Oto-Rhino-Laryngology, Department of Neurosciences, KU Leuven, Leuven, Belgium
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Paek EJ, Murray LL, Newman SD, Kim DJ. Test-retest reliability in an fMRI study of naming in dementia. BRAIN AND LANGUAGE 2019; 191:31-45. [PMID: 30807893 DOI: 10.1016/j.bandl.2019.02.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 12/18/2018] [Accepted: 02/12/2019] [Indexed: 06/09/2023]
Abstract
fMRI has been used as an outcome measure in dementia treatment studies, with many previous studies comparing only single pre- and post-treatment fMRI scans to determine treatment-induced neural changes, while utilizing single subject experimental designs. The purpose of the current study was to evaluate fMRI test-retest reliability in dementia patients and typical older adults using noun and verb confrontation naming to evaluate the validity of using a single pre/post-treatment scan comparison. Seven individuals with dementia and 9 control participants were tested three times over two months using the same fMRI procedures. Differences in individual and group level activation patterns were observed that varied across time. Additionally, the extent of variability fluctuated across individuals, groups, and the grammatical category of target words. Our findings suggested that one time fMRI scanning may inadequately represent an individual's typical brain activation pattern, particularly an individual with dementia. Thus, multiple imaging baselines are recommended.
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Affiliation(s)
- Eun Jin Paek
- Department of Audiology and Speech Pathology, University of Tennessee Health Science Center, Knoxville, TN 37996, United States.
| | - Laura L Murray
- School of Communication Sciences and Disorders, Western University, London, Ontario N6G 1H1, Canada.
| | - Sharlene D Newman
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN 47401, United States.
| | - Dae-Jin Kim
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN 47401, United States.
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Abstract
More than thirty years ago, Alfonso Caramazza laid out assumptions for drawing inferences about the undamaged cognitive system from individuals with brain damage. Since then, these assumptions have been challenged including the transparency or subtractivity assumption, that the cognitive system does not reorganize following brain damage. It has been repeatedly demonstrated that brains are highly plastic. However, there is no clear connection between brain plasticity and cognitive reorganization. Brain plasticity research does not require a rethinking of the core logic of cognitive neuropsychology. Differences in task-based activation between damaged and undamaged brains provide little insight into the cognitive architectures of brain-damaged patients. Theory and methods are needed to understand cognitive neuroplasticity, or how neural reorganization that follows brain damage relates to reorganization of functions. We discuss alternative types of cognitive neuroplasticity that may occur in damaged brains and consider how they impact the basic logic of cognitive neuropsychology.
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Blank IA, Kiran S, Fedorenko E. Can neuroimaging help aphasia researchers? Addressing generalizability, variability, and interpretability. Cogn Neuropsychol 2017; 34:377-393. [PMID: 29188746 PMCID: PMC6157596 DOI: 10.1080/02643294.2017.1402756] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Neuroimaging studies of individuals with brain damage seek to link brain structure and activity to cognitive impairments, spontaneous recovery, or treatment outcomes. To date, such studies have relied on the critical assumption that a given anatomical landmark corresponds to the same functional unit(s) across individuals. However, this assumption is fallacious even across neurologically healthy individuals. Here, we discuss the severe implications of this issue, and argue for an approach that circumvents it, whereby: (i) functional brain regions are defined separately for each subject using fMRI, allowing for inter-individual variability in their precise location; (ii) the response profile of these subject-specific regions are characterized using various other tasks; and (iii) the results are averaged across individuals, guaranteeing generalizabliity. This method harnesses the complementary strengths of single-case studies and group studies, and it eliminates the need for post hoc "reverse inference" from anatomical landmarks back to cognitive operations, thus improving data interpretability.
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Affiliation(s)
- Idan A Blank
- a McGovern Institute for Brain Research , Massachusetts Institute of Technology , Cambridge , MA , USA
| | - Swathi Kiran
- b Department of Speech Language and Hearing Sciences, Aphasia Research Laboratory , Sargent College, Boston University , Boston , MA , USA
| | - Evelina Fedorenko
- c Department of Psychiatry , Massachusetts General Hospital , Charlestown , MA , USA
- d Department of Psychiatry , Harvard Medical School , Boston , MA , USA
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Crosson B, Hampstead BM, Krishnamurthy LC, Krishnamurthy V, McGregor KM, Nocera JR, Roberts S, Rodriguez AD, Tran SM. Advances in neurocognitive rehabilitation research from 1992 to 2017: The ascension of neural plasticity. Neuropsychology 2017; 31:900-920. [PMID: 28857600 DOI: 10.1037/neu0000396] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
OBJECTIVE The last 25 years have seen profound changes in neurocognitive rehabilitation that continue to motivate its evolution. Although the concept of nervous system plasticity was discussed by William James (1890), the foundation for experience-based plasticity had not reached the critical empirical mass to seriously impact rehabilitation research until after 1992. The objective of this review is to describe how the emergence of neural plasticity has changed neurocognitive rehabilitation research. METHOD The important developments included (a) introduction of a widely available tool that could measure brain plasticity (i.e., functional MRI); (b) development of new structural imaging techniques that could define limits of and opportunities for neural plasticity; (c) deployment of noninvasive brain stimulation to leverage neural plasticity for rehabilitation; (d) growth of a literature indicating that exercise has positively impacts neural plasticity, especially for older persons; and (e) enhancement of neural plasticity by creating interventions that generalize beyond the boundaries of treatment activities. Given the massive literature, each of these areas is developed by example. RESULTS The expanding influence of neural plasticity has provided new models and tools for neurocognitive rehabilitation in neural injuries and disorders, as well as methods for measuring neural plasticity and predicting its limits and opportunities. Early clinical trials have provided very encouraging results. CONCLUSION Now that neural plasticity has gained a firm foothold, it will continue to influence the evolution of neurocognitive rehabilitation research for the next 25 years and advance rehabilitation for neural injuries and disease. (PsycINFO Database Record
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Affiliation(s)
- Bruce Crosson
- Veterans Affairs Rehabilitation Research and Development Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center
| | - Benjamin M Hampstead
- Neuropsychology Section, Department of Mental Health Services, Veterans Affairs Ann Arbor Healthcare Systems
| | | | | | | | | | | | - Amy D Rodriguez
- Atlanta Veterans Affairs Rehabilitation Research and Development Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center
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Nouwens F, Visch-Brink EG, Van de Sandt-Koenderman MME, Dippel DWJ, Koudstaal PJ, de Lau LML. Optimal timing of speech and language therapy for aphasia after stroke: more evidence needed. Expert Rev Neurother 2015; 15:885-93. [DOI: 10.1586/14737175.2015.1058161] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Cahana-Amitay D, Albert ML, Oveis A. Psycholinguistics of Aphasia Pharmacotherapy: Asking the Right Questions. APHASIOLOGY 2014; 28:133-154. [PMID: 24489425 PMCID: PMC3904395 DOI: 10.1080/02687038.2013.818099] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
BACKGROUND Among the obstacles to demonstrating efficacy of pharmacological intervention for aphasia is quantifying patients' responses to treatment in a statistically valid and reliable manner. In many of the review papers on this topic (e.g., Berthier et al., 2011; de Boissezon, Peran, de Boysson, & Démonet, 2007; Small & Llano, 2009), detailed discussions of various methodological problems are highlighted, with some suggestions on how these shortcomings should be addressed. Given this deep understanding of caveats associated with the experimental design of aphasia pharmacotherapy studies (e.g., Berthier et al., 2011), investigations continue to produce inconsistent results. AIM In this review paper we suggest that inclusion of theory-driven linguistic measures in aphasia pharmacotherapy studies would add an important step toward elucidating precise patterns of improvement in language performance resulting from pharmacotherapeutic intervention. MAIN CONTRIBUTION We provide a brief review of the clinical approaches currently used in pharmacotherapy studies of aphasia, which often lack psycholinguistic grounding. We then present ways in which psycholinguistic models can complement this approach, offering a rationale for task selection, and as a result, lead to a better understanding of treatment effects. We then follow with an example of how such an integrative approach can be implemented in studies targeting stress reduction in people with aphasia, via beta-blocking agents, as a means to augment language performance, using the psycholinguistic framework of "linguistic anxiety" outlined in Cahana-Amitay et al, 2011 as our guideline. CONCLUSION We conclude that the incorporation of psycholinguistic models into aphasia pharmacotherapy studies can increase the resolution with which we can identify functional changes.
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Affiliation(s)
- Dalia Cahana-Amitay
- Boston University School of Medicine, Department of Neurology, Harold Goodglass Aphasia Research Center, VA Boston Healthcare System, 150 South Huntington Avenue Boston, MA02130
| | - Martin L Albert
- Boston University School of Medicine, Department of Neurology, Harold Goodglass Aphasia Research Center, VA Boston Healthcare System, 150 South Huntington Avenue Boston, MA02130
| | - Abigail Oveis
- Boston University School of Medicine, Department of Neurology, Harold Goodglass Aphasia Research Center, VA Boston Healthcare System, 150 South Huntington Avenue Boston, MA02130
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Thompson CK, Riley EA, den Ouden DB, Meltzer-Asscher A, Lukic S. Training verb argument structure production in agrammatic aphasia: behavioral and neural recovery patterns. Cortex 2013; 49:2358-76. [PMID: 23514929 PMCID: PMC3759546 DOI: 10.1016/j.cortex.2013.02.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Revised: 09/06/2012] [Accepted: 02/04/2013] [Indexed: 11/24/2022]
Abstract
INTRODUCTION Neuroimaging and lesion studies indicate a left hemisphere network for verb and verb argument structure processing, involving both frontal and temporoparietal brain regions. Although their verb comprehension is generally unimpaired, it is well known that individuals with agrammatic aphasia often present with verb production deficits, characterized by an argument structure complexity hierarchy, indicating faulty access to argument structure representations for production and integration into syntactic contexts. Recovery of verb processing in agrammatism, however, has received little attention and no studies have examined the neural mechanisms associated with improved verb and argument structure processing. In the present study we trained agrammatic individuals on verbs with complex argument structure in sentence contexts and examined generalization to verbs with less complex argument structure. The neural substrates of improved verb production were examined using functional magnetic resonance imaging (fMRI). METHODS Eight individuals with chronic agrammatic aphasia participated in the study (four experimental and four control participants). Production of three-argument verbs in active sentences was trained using a sentence generation task emphasizing the verb's argument structure and the thematic roles of sentential noun phrases. Before and after training, production of trained and untrained verbs was tested in naming and sentence production and fMRI scans were obtained, using an action naming task. RESULTS Significant pre- to post-training improvement in trained and untrained (one- and two-argument) verbs was found for treated, but not control, participants, with between-group differences found for verb naming, production of verbs in sentences, and production of argument structure. fMRI activation derived from post-treatment compared to pre-treatment scans revealed upregulation in cortical regions implicated for verb and argument structure processing in healthy controls. CONCLUSIONS Training verb deficits emphasizing argument structure and thematic role mapping is effective for improving verb and sentence production and results in recruitment of neural networks engaged for verb and argument structure processing in healthy individuals.
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Affiliation(s)
- Cynthia K. Thompson
- Aphasia and Neurolinguistics Research Laboratory, Department of Communication Sciences and Disorders, Northwestern University, Evanston, IL, USA
- Department of Neurology, Northwestern University, Evanston, IL, USA
- Cognitive Neurology and Alzheimer’s Disease Center, Northwestern University, Evanston, IL, USA
| | - Ellyn A. Riley
- Department of Communication Sciences and Disorders, Bowling Green State University, USA
| | - Dirk-Bart den Ouden
- Department of Communication Sciences and Disorders, University of South Carolina, USA
| | - Aya Meltzer-Asscher
- Linguistics Department, Tel Aviv University, Israel
- Sagol School of Neuroscience, Tel Aviv University, Israel
| | - Sladjana Lukic
- Aphasia and Neurolinguistics Research Laboratory, Department of Communication Sciences and Disorders, Northwestern University, Evanston, IL, USA
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Kiran S, Ansaldo A, Bastiaanse R, Cherney LR, Howard D, Faroqi-Shah Y, Meinzer M, Thompson CK. Neuroimaging in aphasia treatment research: standards for establishing the effects of treatment. Neuroimage 2013; 76:428-35. [PMID: 23063559 PMCID: PMC3552150 DOI: 10.1016/j.neuroimage.2012.10.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Revised: 07/06/2012] [Accepted: 10/05/2012] [Indexed: 11/29/2022] Open
Abstract
The goal of this paper is to discuss experimental design options available for establishing the effects of treatment in studies that aim to examine the neural mechanisms associated with treatment-induced language recovery in aphasia, using functional magnetic resonance imaging (fMRI). We present both group and single-subject experimental or case-series design options for doing this and address advantages and disadvantages of each. We also discuss general components of and requirements for treatment research studies, including operational definitions of variables, criteria for defining behavioral change and treatment efficacy, and reliability of measurement. Important considerations that are unique to neuroimaging-based treatment research are addressed, pertaining to the relation between the selected treatment approach and anticipated changes in language processes/functions and how such changes are hypothesized to map onto the brain.
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Affiliation(s)
- Swathi Kiran
- Boston University, Sargent College of Health and Rehabilitation Sciences, Boston, MA 02215, USA.
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Kiran S. What is the nature of poststroke language recovery and reorganization? ISRN NEUROLOGY 2012; 2012:786872. [PMID: 23320190 PMCID: PMC3540797 DOI: 10.5402/2012/786872] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Accepted: 11/05/2012] [Indexed: 12/16/2022]
Abstract
This review focuses on three main topics related to the nature of poststroke language recovery and reorganization. The first topic pertains to the nature of anatomical and physiological substrates in the infarcted hemisphere in poststroke aphasia, including the nature of the hemodynamic response in patients with poststroke aphasia, the nature of the peri-infarct tissue, and the neuronal plasticity potential in the infarcted hemisphere. The second section of the paper reviews the current neuroimaging evidence for language recovery in the acute, subacute, and chronic stages of recovery. The third and final section examines changes in connectivity as a function of recovery in poststroke aphasia, specifically in terms of changes in white matter connectivity, changes in functional effective connectivity, and changes in resting state connectivity after stroke. While much progress has been made in our understanding of language recovery, more work needs to be done. Future studies will need to examine whether reorganization of language in poststroke aphasia corresponds to a tighter, more coherent, and efficient network of residual and new regions in the brain. Answering these questions will go a long way towards being able to predict which patients are likely to recover and may benefit from future rehabilitation.
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Affiliation(s)
- Swathi Kiran
- Department of Speech, Language, and Hearing Sciences, Sargent College of Health & Rehabilitation Sciences, Boston University, 635 Commonwealth Avenue, Boston, MA 02215, USA ; Massachusetts General Hospital, Boston, MA, USA
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