1
|
Papageorgiou G, Kasselimis D, Angelopoulou G, Laskaris N, Tsolakopoulos D, Velonakis G, Tountopoulou A, Vassilopoulou S, Potagas C. Investigating Aphasia Recovery: Demographic and Clinical Factors. Brain Sci 2023; 14:7. [PMID: 38275512 PMCID: PMC10813398 DOI: 10.3390/brainsci14010007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Revised: 12/06/2023] [Accepted: 12/11/2023] [Indexed: 01/27/2024] Open
Abstract
Post-stroke language recovery remains one of the main unresolved topics in the field of aphasia. In recent years, there have been efforts to identify specific factors that could potentially lead to improved language recovery. However, the exact relationship between the recovery of particular language functions and possible predictors, such as demographic or lesion variables, is yet to be fully understood. In the present study, we attempted to investigate such relationships in 42 patients with aphasia after left hemisphere stroke, focusing on three language domains: auditory comprehension, naming and speech fluency. Structural imaging data were also obtained for the identification of the lesion sites. According to our findings, patients demonstrated an overall improvement in all three language domains, while no demographic factor significantly contributed to aphasia recovery. Interestingly, specific lesion loci seemed to have a differential effect on language performance, depending on the time of testing (i.e., acute/subacute vs. chronic phase). We argue that this variability concerning lesion-deficit associations reflects the dynamic nature of aphasia and further discuss possible explanations in the framework of neuroplastic changes during aphasia recovery.
Collapse
Affiliation(s)
- Georgios Papageorgiou
- Neuropsychology & Language Disorders Unit, 1st Neurology Department, Eginition Hospital, Faculty of Medicine, National and Kapodistrian University of Athens, 11528 Athens, Greece; (D.K.); (G.A.); (N.L.); (D.T.); (C.P.)
| | - Dimitrios Kasselimis
- Neuropsychology & Language Disorders Unit, 1st Neurology Department, Eginition Hospital, Faculty of Medicine, National and Kapodistrian University of Athens, 11528 Athens, Greece; (D.K.); (G.A.); (N.L.); (D.T.); (C.P.)
- Department of Psychology, Panteion University of Social and Political Sciences, 17671 Athens, Greece
| | - Georgia Angelopoulou
- Neuropsychology & Language Disorders Unit, 1st Neurology Department, Eginition Hospital, Faculty of Medicine, National and Kapodistrian University of Athens, 11528 Athens, Greece; (D.K.); (G.A.); (N.L.); (D.T.); (C.P.)
| | - Nikolaos Laskaris
- Neuropsychology & Language Disorders Unit, 1st Neurology Department, Eginition Hospital, Faculty of Medicine, National and Kapodistrian University of Athens, 11528 Athens, Greece; (D.K.); (G.A.); (N.L.); (D.T.); (C.P.)
- Department of Industrial Design and Production Engineering, School of Engineering, University of West Attica, 12241 Athens, Greece
| | - Dimitrios Tsolakopoulos
- Neuropsychology & Language Disorders Unit, 1st Neurology Department, Eginition Hospital, Faculty of Medicine, National and Kapodistrian University of Athens, 11528 Athens, Greece; (D.K.); (G.A.); (N.L.); (D.T.); (C.P.)
| | - Georgios Velonakis
- 2nd Department of Radiology, General University Hospital “Attikon”, Medical School, National and Kapodistrian University of Athens, 15772 Athens, Greece
| | - Argyro Tountopoulou
- Stroke Unit, 1st Department of Neurology, Eginition Hospital, National and Kapodistrian University of Athens, 15772 Athens, Greece; (A.T.); (S.V.)
| | - Sophia Vassilopoulou
- Stroke Unit, 1st Department of Neurology, Eginition Hospital, National and Kapodistrian University of Athens, 15772 Athens, Greece; (A.T.); (S.V.)
| | - Constantin Potagas
- Neuropsychology & Language Disorders Unit, 1st Neurology Department, Eginition Hospital, Faculty of Medicine, National and Kapodistrian University of Athens, 11528 Athens, Greece; (D.K.); (G.A.); (N.L.); (D.T.); (C.P.)
| |
Collapse
|
2
|
Sihvonen AJ, Vadinova V, Garden KL, Meinzer M, Roxbury T, O'Brien K, Copland D, McMahon KL, Brownsett SLE. Right hemispheric structural connectivity and poststroke language recovery. Hum Brain Mapp 2023; 44:2897-2904. [PMID: 36852658 PMCID: PMC10089089 DOI: 10.1002/hbm.26252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 02/13/2023] [Accepted: 02/15/2023] [Indexed: 03/01/2023] Open
Abstract
Poststroke aphasia typically results from brain damage to the left-lateralized language network. The contribution of the right-lateralized homologues in aphasia recovery remains equivocal. In this longitudinal observational study, we specifically investigated the role of right hemisphere structural connectome in aphasia recovery. Twenty-two patients with aphasia after a left hemispheric stroke underwent comprehensive language assessment at the early subacute and chronic stages. A novel structural connectometry approach, using multi-shell diffusion-weighted MRI data collected at the early subacute stage, was used to evaluate the relationship between right hemisphere white matter connectome and language production and comprehension abilities at early subacute stage. Moreover, we evaluated the relationship between early subacute right hemisphere white matter connectome and longitudinal change in language production and comprehension abilities. All results were corrected for multiple comparisons. Connectometry analyses revealed negative associations between early subacute stage right hemisphere structural connectivity and language production, both cross-sectionally and longitudinally (pFDR < .0125). In turn, only positive associations between right hemisphere structural connectivity and language comprehension were observed, both cross-sectionally and longitudinally (pFDR < .0125). Interhemispheric connectivity was highly associated with comprehension scores. Our results shed light on the discordant interpretations of previous findings, by providing evidence that while some right hemisphere white matter pathways may make a maladaptive contribution to the recovery of language, other pathways support the recovery of language, especially comprehension abilities.
Collapse
Affiliation(s)
- Aleksi J Sihvonen
- Queensland Aphasia Research Centre, University of Queensland, Herston, Australia.,School of Health and Rehabilitation Sciences, University of Queensland, Brisbane, Australia.,Centre of Research Excellence in Aphasia Recovery and Rehabilitation, La Trobe University, Melbourne, Australia.,Cognitive Brain Research Unit (CBRU), University of Helsinki, Helsinki, Finland.,Centre of Excellence in Music, Mind, Body and Brain, University of Helsinki, Helsinki, Finland
| | - Veronika Vadinova
- Queensland Aphasia Research Centre, University of Queensland, Herston, Australia.,School of Health and Rehabilitation Sciences, University of Queensland, Brisbane, Australia.,Centre of Research Excellence in Aphasia Recovery and Rehabilitation, La Trobe University, Melbourne, Australia
| | - Kimberley L Garden
- Queensland Aphasia Research Centre, University of Queensland, Herston, Australia.,School of Health and Rehabilitation Sciences, University of Queensland, Brisbane, Australia.,Centre of Research Excellence in Aphasia Recovery and Rehabilitation, La Trobe University, Melbourne, Australia
| | - Marcus Meinzer
- Department of Neurology, University Medicine Greifswald, Greifswald, Germany
| | - Tracy Roxbury
- Queensland Aphasia Research Centre, University of Queensland, Herston, Australia
| | - Kate O'Brien
- Queensland Aphasia Research Centre, University of Queensland, Herston, Australia
| | - David Copland
- Queensland Aphasia Research Centre, University of Queensland, Herston, Australia.,School of Health and Rehabilitation Sciences, University of Queensland, Brisbane, Australia.,Centre of Research Excellence in Aphasia Recovery and Rehabilitation, La Trobe University, Melbourne, Australia
| | - Katie L McMahon
- School of Clinical Sciences, Centre for Biomedical Technologies, Queensland University of Technology, Brisbane, Australia
| | - Sonia L E Brownsett
- Queensland Aphasia Research Centre, University of Queensland, Herston, Australia.,School of Health and Rehabilitation Sciences, University of Queensland, Brisbane, Australia.,Centre of Research Excellence in Aphasia Recovery and Rehabilitation, La Trobe University, Melbourne, Australia
| |
Collapse
|
3
|
Dresang HC, Harvey DY, Xie SX, Shah-Basak PP, DeLoretta L, Wurzman R, Parchure SY, Sacchetti D, Faseyitan O, Lohoff FW, Hamilton RH. Genetic and Neurophysiological Biomarkers of Neuroplasticity Inform Post-Stroke Language Recovery. Neurorehabil Neural Repair 2022; 36:371-380. [PMID: 35428413 PMCID: PMC9133188 DOI: 10.1177/15459683221096391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND There is high variability in post-stroke aphasia severity and predicting recovery remains imprecise. Standard prognostics do not include neurophysiological indicators or genetic biomarkers of neuroplasticity, which may be critical sources of variability. OBJECTIVE To evaluate whether a common polymorphism (Val66Met) in the gene for brain-derived neurotrophic factor (BDNF) contributes to variability in post-stroke aphasia, and to assess whether BDNF polymorphism interacts with neurophysiological indicators of neuroplasticity (cortical excitability and stimulation-induced neuroplasticity) to improve estimates of aphasia severity. METHODS Saliva samples and motor-evoked potentials (MEPs) were collected from participants with chronic aphasia subsequent to left-hemisphere stroke. MEPs were collected prior to continuous theta burst stimulation (cTBS; index for cortical excitability) and 10 minutes following cTBS (index for stimulation-induced neuroplasticity) to the right primary motor cortex. Analyses assessed the extent to which BDNF polymorphism interacted with cortical excitability and stimulation-induced neuroplasticity to predict aphasia severity beyond established predictors. RESULTS Val66Val carriers showed less aphasia severity than Val66Met carriers, after controlling for lesion volume and time post-stroke. Furthermore, Val66Val carriers showed expected effects of age on aphasia severity, and positive associations between severity and both cortical excitability and stimulation-induced neuroplasticity. In contrast, Val66Met carriers showed weaker effects of age and negative associations between cortical excitability, stimulation-induced neuroplasticity and aphasia severity. CONCLUSIONS Neurophysiological indicators and genetic biomarkers of neuroplasticity improved aphasia severity predictions. Furthermore, BDNF polymorphism interacted with cortical excitability and stimulation-induced neuroplasticity to improve predictions. These findings provide novel insights into mechanisms of variability in stroke recovery and may improve aphasia prognostics.
Collapse
Affiliation(s)
- Haley C. Dresang
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, 3710 Hamilton Walk, Philadelphia, PA 19104,Moss Rehabilitation Research Institute, Einstein Medical Center, 50 Township Line Road, Philadelphia, PA 19027,Corresponding author:, Department of Neurology, University of Pennsylvania, Perelman School of Medicine, 3710 Hamilton Walk, Philadelphia, PA 19104
| | - Denise Y. Harvey
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, 3710 Hamilton Walk, Philadelphia, PA 19104
| | - Sharon Xiangwen Xie
- Department of Biostatistics, Epidemiology, and Informatics, University of Pennsylvania, Perelman School of Medicine, 607 Blockley Hall, 423 Guardian Drive, Philadelphia, PA 19104
| | - Priyanka P. Shah-Basak
- Medical College of Wisconsin, Department of Neurology, 8701 Watertown Plank Road Milwaukee, WI 53226
| | - Laura DeLoretta
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, 3710 Hamilton Walk, Philadelphia, PA 19104
| | - Rachel Wurzman
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, 3710 Hamilton Walk, Philadelphia, PA 19104
| | - Shreya Y. Parchure
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, 3710 Hamilton Walk, Philadelphia, PA 19104
| | - Daniela Sacchetti
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, 3710 Hamilton Walk, Philadelphia, PA 19104
| | - Olufunsho Faseyitan
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, 3710 Hamilton Walk, Philadelphia, PA 19104
| | - Falk W. Lohoff
- National Institute for Alcohol Abuse and Alcoholism, National Institutes of Health (NIH), 10 Center Drive (10CRC/2-2352), Bethesda, MD 20892
| | - Roy H. Hamilton
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, 3710 Hamilton Walk, Philadelphia, PA 19104
| |
Collapse
|
4
|
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] [What about the content of this article? (0)] [Affiliation(s)] [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.
Collapse
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
| |
Collapse
|
5
|
Pisano F, Caltagirone C, Incoccia C, Marangolo P. DUAL-tDCS Treatment over the Temporo-Parietal Cortex Enhances Writing Skills: First Evidence from Chronic Post-Stroke Aphasia. Life (Basel) 2021; 11:343. [PMID: 33919714 DOI: 10.3390/life11040343] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 04/10/2021] [Accepted: 04/12/2021] [Indexed: 12/12/2022] Open
Abstract
The learning of writing skills involves the re-engagement of previously established independent procedures. Indeed, the writing deficit an adult may acquire after left hemispheric brain injury is caused by either an impairment to the lexical route, which processes words as a whole, to the sublexical procedure based on phoneme-to-grapheme conversion rules, or to both procedures. To date, several approaches have been proposed for writing disorders, among which, interventions aimed at restoring the sub-lexical procedure were successful in cases of severe agraphia. In a randomized double-blind crossover design, fourteen chronic Italian post-stroke aphasics underwent dual transcranial direct current stimulation (tDCS) (20 min, 2 mA) with anodal and cathodal current simultaneously placed over the left and right temporo-parietal cortex, respectively. Two different conditions were considered: (1) real, and (2) sham, while performing a writing task. Each experimental condition was performed for ten workdays over two weeks. After real stimulation, a greater amelioration in writing with respect to the sham was found. Relevantly, these effects generalized to different language tasks not directly treated. This evidence suggests, for the first time, that dual tDCS associated with training is efficacious for severe agraphia. Our results confirm the critical role of the temporo-parietal cortex in writing skills.
Collapse
|
6
|
Chang YN, Lambon Ralph MA. A unified neurocomputational bilateral model of spoken language production in healthy participants and recovery in poststroke aphasia. Proc Natl Acad Sci U S A 2020; 117:32779-90. [PMID: 33273118 DOI: 10.1073/pnas.2010193117] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Studies of healthy and impaired language have generated many verbally described hypotheses. While these verbal descriptions have advanced our understanding of language processing, some explanations are mutually incompatible, and it is unclear how they work mechanistically. We constructed a neurocomputational bilateral model of spoken language production to simulate a range of phenomena in healthy participants and patients with aphasia simultaneously, including language lateralization, impaired performance after left but not right damage, and hemispheric involvement in plasticity-dependent recovery. The model demonstrates how seemly contradictory findings can be simulated within a single framework. This provides a coherent mechanistic account of language lateralization and recovery from poststroke aphasia. Understanding the processes underlying normal, impaired, and recovered language performance has been a long-standing goal for cognitive and clinical neuroscience. Many verbally described hypotheses about language lateralization and recovery have been generated. However, they have not been considered within a single, unified, and implemented computational framework, and the literatures on healthy participants and patients are largely separated. These investigations also span different types of data, including behavioral results and functional MRI brain activations, which augment the challenge for any unified theory. Consequently, many key issues, apparent contradictions, and puzzles remain to be solved. We developed a neurocomputational, bilateral pathway model of spoken language production, designed to provide a unified framework to simulate different types of data from healthy participants and aphasic patients. The model encapsulates key computational principles (differential computational capacity, emergent division of labor across pathways, experience-dependent plasticity-related recovery) and provides an explanation for the bilateral yet asymmetric lateralization of language in healthy participants, chronic aphasia after left rather than right hemisphere lesions, and the basis of partial recovery in patients. The model provides a formal basis for understanding the relationship between behavioral performance and brain activation. The unified model is consistent with the degeneracy and variable neurodisplacement theories of language recovery, and adds computational insights to these hypotheses regarding the neural machinery underlying language processing and plasticity-related recovery following damage.
Collapse
|
7
|
van Zyl M, Pillay B, Kritzinger A, Lekganyane M, Graham M. Significance of speech production errors on cross-linguistic processing in Sepedi-English individuals with bilingual aphasia: a case series analysis. Top Stroke Rehabil 2019; 26:294-306. [PMID: 30913996 DOI: 10.1080/10749357.2019.1593612] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND Bilingual aphasia forms a significant part of speech-language pathologists' (SLP) caseload, globally, and specifically in South Africa. Few tools supporting clinical decision-making are available due to limited understanding of typical and disordered cross-linguistic processing (how the languages interact). Speech errors may provide insight about "hidden" bilingual mechanisms. OBJECTIVES To determine what speech errors can impart about cross-linguistic processing, as well as, associated language and impairment variables in Sepedi-English individuals with aphasia. METHOD The case series included six participants, purposively selected from three rehabilitation sites in South Africa. Detailed language and clinical profiles were obtained. Participants performed a confrontation naming task in their most dominant (MDL) and less dominant language (LDL). Responses were audio recorded, transcribed, and analyzed for overall accuracy and error type in MDL and LDL; verified by a Sepedi-speaking linguist and a qualified SLP. RESULTS (1) No statistically significant differences in MDL-LDL naming accuracy were found, supporting recent literature of simultaneous inter-activation of both languages and shared word retrieval mechanisms. All types of speech errors occurred, and semantic errors were produced most frequently and consistently in each participant's MDL and LDL. (2) Language proficiency, language recovery patterns, and aphasia type (Broca's and Anomic) and severity (mild and/or moderate) appeared to be more strongly linked to cross-linguistic processing than Sepedi-English linguistic differences and age of acquisition of both languages. CONCLUSIONS Participants with bilingual aphasia may use typical cross-linguistic and word retrieval mechanisms, concurring with current theories of bilingualism. Findings are preliminary, warranting investigations of other language tasks, modalities, pairs, and related variables.
Collapse
Affiliation(s)
- Mianda van Zyl
- a Department of Speech-Language Pathology and Audiology , University of Pretoria , Pretoria , South Africa
| | - Bhavani Pillay
- a Department of Speech-Language Pathology and Audiology , University of Pretoria , Pretoria , South Africa
| | - Alta Kritzinger
- a Department of Speech-Language Pathology and Audiology , University of Pretoria , Pretoria , South Africa
| | - Matemane Lekganyane
- c Department of African Languages , University of Pretoria , Pretoria , South Africa
| | - Marien Graham
- b Department of Science, Mathematics and Technology Education , University of Pretoria , Pretoria , South Africa
| |
Collapse
|
8
|
Abstract
Objective: To review the research literature pertaining to post-stroke language recovery, and to discuss neurocognitive assessment in patients in the context of aphasia, time course of language recovery, factors associated with language recovery, and therapeutic techniques designed to facilitate language recovery. Method: Articles were identified through PubMed, MEDLINE, PsychINFO, and Google Scholar searches. Examples of utilized keywords include "post-stroke aphasia," "post-stroke language recovery," "post-stroke neurocognitive assessment," and "neuropsychology and aphasia." Results: Most language recovery occurs in the first few weeks following stroke, but residual recovery may occur for many years. Although initial aphasia severity is the single largest determinant of post-stroke language recovery, a number of other variables also contribute. Several techniques have been developed to aid in the recovery process including speech-language therapy and noninvasive brain stimulation, although the effectiveness of acute and subacute treatment remains unclear. Some degree of valid neurocognitive assessment is possible in patients with aphasia, and the information gained from such an evaluation can aid the rehabilitative process Conclusions: Significant recovery of language function is possible following a stroke, but prediction of level of recovery in an individual patient is difficult. Information about initial aphasia severity and the integrity of cognitive domains other than language can help guide the rehabilitation team, as well as manage expectations for recovery.
Collapse
Affiliation(s)
- Adam Gerstenecker
- a Department of Neurology , University of Alabama at Birmingham , Birmingham , AL, USA.,b Alzheimer's Disease Center , University of Alabama at Birmingham , Birmingham , AL, USA.,c Evelyn F. McKnight Brain Institute , University of Alabama at Birmingham , Birmingham , AL, USA
| | - Ronald M Lazar
- a Department of Neurology , University of Alabama at Birmingham , Birmingham , AL, USA.,c Evelyn F. McKnight Brain Institute , University of Alabama at Birmingham , Birmingham , AL, USA
| |
Collapse
|
9
|
Alferova VV, Mayorova LA, Ivanova EG, Guekht AB, Shklovskij VM. [Functional neuroimaging of the brain structures associated with language in healthy individuals and patients with post-stroke aphasia]. Zh Nevrol Psikhiatr Im S S Korsakova 2017; 117:71-78. [PMID: 28665373 DOI: 10.17116/jnevro20171173271-78] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The introduction of non-invasive functional neuroimaging techniques such as functional magnetic resonance imaging (fMRI), in the practice of scientific and clinical research can increase our knowledge about the organization of cognitive processes, including language, in normal and reorganization of these cognitive functions in post-stroke aphasia. The article discusses the results of fMRI studies of functional organization of the cortex of a healthy adult's brain in the processing of various voice information as well as the main types of speech reorganization after post-stroke aphasia in different stroke periods. The concepts of 'effective' and 'ineffective' brain plasticity in post-stroke aphasia were considered. It was concluded that there was an urgent need for further comprehensive studies, including neuropsychological testing and several complementary methods of functional neuroimaging, to develop a phased treatment plan and neurorehabilitation of patients with post-stroke aphasia.
Collapse
Affiliation(s)
- V V Alferova
- Center for Speech Pathology and Neurorehabilitation, Moscow, Russia; Pirogov Russian National Research Medical University, Moscow, Russia
| | - L A Mayorova
- Center for Speech Pathology and Neurorehabilitation, Moscow, Russia; Institute of Higher Nervous Activity of RAS, Moscow, Russia
| | - E G Ivanova
- Center for Speech Pathology and Neurorehabilitation, Moscow, Russia; Pirogov Russian National Research Medical University, Moscow, Russia
| | - A B Guekht
- Pirogov Russian National Research Medical University, Moscow, Russia; The Solovyov Scientific and Practical Centre of neuropsychiatric, Moscow, Russia
| | - V M Shklovskij
- Center for Speech Pathology and Neurorehabilitation, Moscow, Russia; The Serbsky State Scientific Center for Psychiatry and Narcology, Moscow, Russia
| |
Collapse
|
10
|
Westmacott R, McAndrews MP, deVeber G. Language Representation Following Left MCA Stroke in Children and Adults: An fMRI Study. Can J Neurol Sci 2017; 44:483-97. [PMID: 28468691 DOI: 10.1017/cjn.2017.44] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND In this case series, functional magnetic resonance imaging was used to examine brain networks that mediate different aspects of language function in 4 young adults (17-22 years) with a history of left middle cerebral artery (MCA) stroke in childhood (40 years of age). Although it is widely believed that altered lateralization patterns are more likely to occur following early brain injuries compared with later brain injuries, the presumed plasticity of the young brain has been challenged in recent years, particularly in the domain of language. METHODS We explored this issue by contrasting the brain activation patterns of individuals with childhood left MCA stroke and adult left MCA stroke while performing two language tasks: verb generation and picture-word matching. Importantly, both groups showed significant recovery of language function, based on standard clinical indicators. RESULTS Controls showed left lateralized activation for both tasks, although much more pronounced for verb generation. Adult stroke patients also showed left lateralization for both tasks, though somewhat weaker than controls. Childhood stroke patients exhibited significantly weaker lateralization than the adult group for verb generation, but there was no significant group difference for picture-word matching. CONCLUSIONS These preliminary findings suggest that successful reorganization of language function is more likely to involve bilateral recruitment following left MCA stroke in childhood than in adulthood. Of importance, although childhood stroke patients had primarily subcortical lesions, there were substantial alterations in cortical activation patterns.
Collapse
|
11
|
Sandberg CW. Hypoconnectivity of Resting-State Networks in Persons with Aphasia Compared with Healthy Age-Matched Adults. Front Hum Neurosci 2017; 11:91. [PMID: 28293185 PMCID: PMC5329062 DOI: 10.3389/fnhum.2017.00091] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 02/14/2017] [Indexed: 01/21/2023] Open
Abstract
Aphasia is a language disorder affecting more than one million people in the US. While language function has traditionally been the focus of neuroimaging research, other cognitive functions are affected in this population, which has implications not only for those specific processes but also for the interaction of language and other cognitive functions. Resting state fMRI (rs-fMRI) is a practical and informative way to explore and characterize general cognitive engagement and/or health in this population, but it is currently underutilized. The aim of this study was to explore the functional connectivity in resting state networks (RSNs) and in the semantic network in seven persons with aphasia (PWA) who were at least 6 months post onset compared with 11 neurologically healthy adults (NHA) in order to gain a more comprehensive understanding of general cognitive engagement in aphasia. These preliminary results show that PWA exhibit hypoconnectivity in the semantic network and all RSNs except the visual network. Compared with NHA, PWA appear to have fewer cross- and left-hemispheric connections. However, PWA exhibit some stronger connections than NHA within the semantic network, which could indicate compensatory mechanisms. Importantly, connectivity for RSNs appear to increase with decreasing aphasia severity and decrease with increasing lesion size. This knowledge has the potential to improve aphasia therapy by furthering the understanding of lesion effects on the cognitive system as a whole, which can guide treatment target selection and promotion of favorable neural reorganization for optimal recovery of function.
Collapse
Affiliation(s)
- Chaleece W Sandberg
- Adult Neuroplasticity Laboratory, Department of Communication Sciences and Disorders, Penn State University University Park, PA, USA
| |
Collapse
|
12
|
Griffis JC, Nenert R, Allendorfer JB, Vannest J, Holland S, Dietz A, Szaflarski JP. The canonical semantic network supports residual language function in chronic post-stroke aphasia. Hum Brain Mapp 2016; 38:1636-1658. [PMID: 27981674 DOI: 10.1002/hbm.23476] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 11/11/2016] [Accepted: 11/15/2016] [Indexed: 12/28/2022] Open
Abstract
Current theories of language recovery after stroke are limited by a reliance on small studies. Here, we aimed to test predictions of current theory and resolve inconsistencies regarding right hemispheric contributions to long-term recovery. We first defined the canonical semantic network in 43 healthy controls. Then, in a group of 43 patients with chronic post-stroke aphasia, we tested whether activity in this network predicted performance on measures of semantic comprehension, naming, and fluency while controlling for lesion volume effects. Canonical network activation accounted for 22%-33% of the variance in language test scores. Whole-brain analyses corroborated these findings, and revealed a core set of regions showing positive relationships to all language measures. We next evaluated the relationship between activation magnitudes in left and right hemispheric portions of the network, and characterized how right hemispheric activation related to the extent of left hemispheric damage. Activation magnitudes in each hemispheric network were strongly correlated, but four right frontal regions showed heightened activity in patients with large lesions. Activity in two of these regions (inferior frontal gyrus pars opercularis and supplementary motor area) was associated with better language abilities in patients with larger lesions, but poorer language abilities in patients with smaller lesions. Our results indicate that bilateral language networks support language processing after stroke, and that right hemispheric activations related to extensive left hemispheric damage occur outside of the canonical semantic network and differentially relate to behavior depending on the extent of left hemispheric damage. Hum Brain Mapp 38:1636-1658, 2017. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Joseph C Griffis
- Department of Psychology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Rodolphe Nenert
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Jane B Allendorfer
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama
| | | | - Scott Holland
- Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Aimee Dietz
- University of Cincinnati Academic Health Center, Cincinnati, Ohio
| | - Jerzy P Szaflarski
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama
| |
Collapse
|
13
|
Kielar A, Deschamps T, Jokel R, Meltzer JA. Functional reorganization of language networks for semantics and syntax in chronic stroke: Evidence from MEG. Hum Brain Mapp 2016; 37:2869-93. [PMID: 27091757 DOI: 10.1002/hbm.23212] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 03/29/2016] [Accepted: 04/04/2016] [Indexed: 11/09/2022] Open
Abstract
Using magnetoencephalography, we investigated the potential of perilesional and contralesional activity to support language recovery in patients with poststroke aphasia. In healthy young controls, left-lateralized ventral frontotemporal regions responded to semantic anomalies during sentence comprehension and bilateral dorsal frontoparietal regions responded to syntactic anomalies. Older adults showed more extensive bilateral responses to the syntactic anomalies and less lateralized responses to the semantic anomalies, with decreased activation in the left occipital and parietal regions for both semantic and syntactic anomalies. In aphasic participants, we observed compensatory recruitment in the right hemisphere (RH), which varied depending on the type of linguistic information that was processed. For semantic anomalies, aphasic patients activated some preserved left hemisphere regions adjacent to the lesion, as well as homologous parietal and temporal RH areas. Patients also recruited right inferior and dorsolateral frontal cortex that was not activated in the healthy participants. Responses for syntactic anomalies did not reach significance in patients. Correlation analyses indicated that recruitment of homologous temporoparietal RH areas is associated with better semantic performance, whereas higher accuracy on the syntactic task was related to bilateral superior temporoparietal and right frontal activity. The results suggest that better recovery of semantic processing is associated with a shift to ventral brain regions in the RH. In contrast, preservation of syntactic processing is mediated by dorsal areas, bilaterally, although recovery of syntactic processing tends to be poorer than semantic. Hum Brain Mapp 37:2869-2893, 2016. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Aneta Kielar
- Rotman Research Institute, Baycrest Health Sciences Toronto, Toronto, Ontario, Canada.,Canadian Partnership for Stroke Recovery, Ottawa, Ontario, Canada
| | - Tiffany Deschamps
- Rotman Research Institute, Baycrest Health Sciences Toronto, Toronto, Ontario, Canada
| | - Regina Jokel
- Rotman Research Institute, Baycrest Health Sciences Toronto, Toronto, Ontario, Canada.,Department of Speech-Language Pathology, University of Toronto, Toronto, Ontario, Canada
| | - Jed A Meltzer
- Rotman Research Institute, Baycrest Health Sciences Toronto, Toronto, Ontario, Canada.,Department of Psychology, University of Toronto, Toronto, Ontario, Canada.,Department of Speech-Language Pathology, University of Toronto, Toronto, Ontario, Canada.,Canadian Partnership for Stroke Recovery, Ottawa, Ontario, Canada
| |
Collapse
|
14
|
Kiran S, Meier EL, Kapse KJ, Glynn PA. Changes in task-based effective connectivity in language networks following rehabilitation in post-stroke patients with aphasia. Front Hum Neurosci 2015; 9:316. [PMID: 26106314 PMCID: PMC4460429 DOI: 10.3389/fnhum.2015.00316] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Accepted: 05/18/2015] [Indexed: 11/19/2022] Open
Abstract
In this study, we examined regions in the left and right hemisphere language network that were altered in terms of the underlying neural activation and effective connectivity subsequent to language rehabilitation. Eight persons with chronic post-stroke aphasia and eight normal controls participated in the current study. Patients received a 10 week semantic feature-based rehabilitation program to improve their skills. Therapy was provided on atypical examples of one trained category while two control categories were monitored; the categories were counterbalanced across patients. In each fMRI session, two experimental tasks were conducted: (a) picture naming and (b) semantic feature verification of trained and untrained categories. Analysis of treatment effect sizes revealed that all patients showed greater improvements on the trained category relative to untrained categories. Results from this study show remarkable patterns of consistency despite the inherent variability in lesion size and activation patterns across patients. Across patients, activation that emerged as a function of rehabilitation on the trained category included bilateral IFG, bilateral SFG, LMFG, and LPCG for picture naming; and bilateral IFG, bilateral MFG, LSFG, and bilateral MTG for semantic feature verification. Analysis of effective connectivity using Dynamic Causal Modeling (DCM) indicated that LIFG was the consistently significantly modulated region after rehabilitation across participants. These results indicate that language networks in patients with aphasia resemble normal language control networks and that this similarity is accentuated by rehabilitation.
Collapse
Affiliation(s)
- Swathi Kiran
- Aphasia Research Laboratory, Speech Language and Hearing Sciences, Sargent College, Boston University Boston MA, USA
| | - Erin L Meier
- Aphasia Research Laboratory, Speech Language and Hearing Sciences, Sargent College, Boston University Boston MA, USA
| | - Kushal J Kapse
- Aphasia Research Laboratory, Speech Language and Hearing Sciences, Sargent College, Boston University Boston MA, USA
| | - Peter A Glynn
- Feinberg School of Medicine, Northwestern University Chicago IL, USA
| |
Collapse
|
15
|
Costa V, Giglia G, Brighina F, Indovino S, Fierro B. Ipsilesional and contralesional regions participate in the improvement of poststroke aphasia: a transcranial direct current stimulation study. Neurocase 2015; 21:479-88. [PMID: 24957199 DOI: 10.1080/13554794.2014.927508] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
In the past few years, noninvasive cerebral stimulations have been used to modulate language task performance in healthy and aphasic patients. In this study, a dual transcranial direct current stimulation (tDCS) on anterior and posterior language areas was applied for 2 weeks to a patient with a possible crossed aphasia following a right hemisphere stroke. Inhibitory cathodal stimulation of the right Brodmann areas (BA) 44/45 and simultaneous anodal stimulation of the left BA 44/45 improved the patient's performance in picture naming. Conversely, the same bilateral montage on BA 39/40 did not produce any significant improvement; finally, electrode polarity inversion over BA 39/40 yielded a further improvement compared with the first anterior stimulation. Our findings suggest that ipsilesional and contralesional areas could be useful in poststroke functional reorganization and provide new evidences for the therapeutic value of tDCS in aphasia.
Collapse
Affiliation(s)
- Vanessa Costa
- a Department of Experimental BioMedicine and Clinical Neurosciences (BioNeC) , University of Palermo , Palermo , Italy
| | | | | | | | | |
Collapse
|
16
|
Marangolo P, Fiori V, Gelfo F, Shofany J, Razzano C, Caltagirone C, Angelucci F. Bihemispheric tDCS enhances language recovery but does not alter BDNF levels in chronic aphasic patients. Restor Neurol Neurosci 2014; 32:367-79. [PMID: 24398720 DOI: 10.3233/rnn-130323] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
PURPOSE Several studies have shown that transcranial direct current stimulation (tDCS) is a useful tool to enhance language recovery in aphasia. It has also been suggested that modulation of the neurotrophin brain-derived neurotrophic factor (BDNF) might be part of the mechanisms involved in tDCS effects on synaptic connectivity. However, all language studies have previously investigated the effects using unihemispheric stimulation. The purpose of the present study is to investigate the role of bihemispheric tDCS on language recovery and BDNF serum levels. METHODS Seven aphasic persons underwent an intensive language therapy in two different conditions: real bihemispheric stimulation over the left and right Broca's areas and a sham condition. RESULTS After the stimulation, patients exibited a significant recovery in three language tasks (picture description, noun and verb naming) compared to the sham condition which persisted in the follow-up session. No significant differences were found in BDNF serum levels after tDCS stimulation and in the follow-up session. However, a significant positive correlation was present for the real stimulation condition between percent changes in BDNF levels and in the verb naming task. CONCLUSIONS The data suggest that this novel approach may potentiate the recovery of language in chronic aphasia. They also emphasize the importance to further investigate the role of possible biomarkers associated with tDCS treatment response in language recovery.
Collapse
Affiliation(s)
- Paola Marangolo
- Facoltà di Medicina, Università Politecnica Marche, Ancona, Italy IRCCS Fondazione Santa Lucia, Roma, Italy
| | | | - Francesca Gelfo
- IRCCS Fondazione Santa Lucia, Roma, Italy Dipartimento di Medicina dei Sistemi, Università degli studi di Roma "Tor Vergata", Roma, Italy
| | | | | | - Carlo Caltagirone
- IRCCS Fondazione Santa Lucia, Roma, Italy Dipartimento di Medicina dei Sistemi, Università degli studi di Roma "Tor Vergata", Roma, Italy
| | | |
Collapse
|
17
|
Forkel SJ, Thiebaut de Schotten M, Dell'Acqua F, Kalra L, Murphy DGM, Williams SCR, Catani M. Anatomical predictors of aphasia recovery: a tractography study of bilateral perisylvian language networks. ACTA ACUST UNITED AC 2014; 137:2027-39. [PMID: 24951631 DOI: 10.1093/brain/awu113] [Citation(s) in RCA: 223] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Stroke-induced aphasia is associated with adverse effects on quality of life and the ability to return to work. For patients and clinicians the possibility of relying on valid predictors of recovery is an important asset in the clinical management of stroke-related impairment. Age, level of education, type and severity of initial symptoms are established predictors of recovery. However, anatomical predictors are still poorly understood. In this prospective longitudinal study, we intended to assess anatomical predictors of recovery derived from diffusion tractography of the perisylvian language networks. Our study focused on the arcuate fasciculus, a language pathway composed of three segments connecting Wernicke's to Broca's region (i.e. long segment), Wernicke's to Geschwind's region (i.e. posterior segment) and Broca's to Geschwind's region (i.e. anterior segment). In our study we were particularly interested in understanding how lateralization of the arcuate fasciculus impacts on severity of symptoms and their recovery. Sixteen patients (10 males; mean age 60 ± 17 years, range 28-87 years) underwent post stroke language assessment with the Revised Western Aphasia Battery and neuroimaging scanning within a fortnight from symptoms onset. Language assessment was repeated at 6 months. Backward elimination analysis identified a subset of predictor variables (age, sex, lesion size) to be introduced to further regression analyses. A hierarchical regression was conducted with the longitudinal aphasia severity as the dependent variable. The first model included the subset of variables as previously defined. The second model additionally introduced the left and right arcuate fasciculus (separate analysis for each segment). Lesion size was identified as the only independent predictor of longitudinal aphasia severity in the left hemisphere [beta = -0.630, t(-3.129), P = 0.011]. For the right hemisphere, age [beta = -0.678, t(-3.087), P = 0.010] and volume of the long segment of the arcuate fasciculus [beta = 0.730, t(2.732), P = 0.020] were predictors of longitudinal aphasia severity. Adding the volume of the right long segment to the first-level model increased the overall predictive power of the model from 28% to 57% [F(1,11) = 7.46, P = 0.02]. These findings suggest that different predictors of recovery are at play in the left and right hemisphere. The right hemisphere language network seems to be important in aphasia recovery after left hemispheric stroke.
Collapse
Affiliation(s)
- Stephanie J Forkel
- 1 Research Department of Clinical, Educational, and Health Psychology (RDCEHP), Division of Psychology and Language Sciences, Faculty of Brain Sciences, University College London, UK2 Natbrainlab, Department of Neuroimaging, Institute of Psychiatry, King's College London, UK
| | - Michel Thiebaut de Schotten
- 3 Natbrainlab, Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, King's College London, London, UK4 Inserm U1127; UPMC-Paris6, UMR_S 1127; CNRS UMR 7225, Centre de Recherche de l'Institut du Cerveau et de la Moelle épinière, Groupe Hospitalier Pitié-Salpêtrière, 75013 Paris, France
| | - Flavio Dell'Acqua
- 2 Natbrainlab, Department of Neuroimaging, Institute of Psychiatry, King's College London, UK5 NIHR Biomedical Research Centre for Mental Health at South London and Maudsley NHS Foundation Trust and King's College London, London, UK
| | - Lalit Kalra
- 6 Department of Clinical Neuroscience, Institute of Psychiatry, King's College London, London, UK
| | - Declan G M Murphy
- 7 Sackler Institute for Translational Neurodevelopment and Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, King's College London, UK
| | - Steven C R Williams
- 2 Natbrainlab, Department of Neuroimaging, Institute of Psychiatry, King's College London, UK5 NIHR Biomedical Research Centre for Mental Health at South London and Maudsley NHS Foundation Trust and King's College London, London, UK
| | - Marco Catani
- 3 Natbrainlab, Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, King's College London, London, UK
| |
Collapse
|
18
|
Fiori V, Cipollari S, Caltagirone C, Marangolo P. "If two witches would watch two watches, which witch would watch which watch?" tDCS over the left frontal region modulates tongue twister repetition in healthy subjects. Neuroscience 2013; 256:195-200. [PMID: 24184977 DOI: 10.1016/j.neuroscience.2013.10.048] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Revised: 09/26/2013] [Accepted: 10/22/2013] [Indexed: 11/19/2022]
Abstract
Recent studies have demonstrated that transcranial direct current stimulation (tDCS) modulates cortical activity in the human brain. In the language domain, it has already been shown that during a naming task tDCS reduces vocal reaction times in healthy individuals and speeds up the recovery process in left brain-damaged aphasic subjects. In this study, we wondered whether tDCS would influence the ability to articulate tongue twisters during a repetition task. Three groups of 10 healthy individuals were asked to repeat a list of tongue twisters in three different stimulation conditions: one group performed the task during anodal tDCS (atDCS) (20 min, 2 mA) over the left frontal region; a second group during cathodal tDCS delivered over the same region; and, in a third group, sham stimulation was applied. Accuracy and vocal reaction times in repeating each tongue twister before, during and 1h after the stimulation were recorded. Participants were more accurate and faster at repeating the stimuli during atDCS than at baseline, while cathodal tDCS significantly reduced their performance in terms of accuracy and reaction times. No significant differences were observed among the three time points during the sham condition. We believe that these data clearly confirm that the left frontal region is critically involved in the process of speech repetition. They are also in line with recent evidence suggesting that frontal tDCS might be used as a therapeutic tool in patients suffering from articulatory deficits.
Collapse
Affiliation(s)
- V Fiori
- IRCCS Fondazione Santa Lucia, Roma, Italy
| | | | - C Caltagirone
- Università di Tor Vergata, Roma, Italy; IRCCS Fondazione Santa Lucia, Roma, Italy
| | - P Marangolo
- Facoltà di Medicina, Università Politecnica delle Marche, Ancona, Italy; IRCCS Fondazione Santa Lucia, Roma, Italy.
| |
Collapse
|
19
|
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] [What about the content of this article? (0)] [Affiliation(s)] [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.
Collapse
Affiliation(s)
- Swathi Kiran
- Boston University, Sargent College of Health and Rehabilitation Sciences, Boston, MA 02215, USA.
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Eaton KP, Szaflarski JP, Altaye M, Ball AL, Kissela BM, Banks C, Holland SK. Reliability of fMRI for studies of language in post-stroke aphasia subjects. Neuroimage 2008; 41:311-22. [PMID: 18411061 PMCID: PMC2474692 DOI: 10.1016/j.neuroimage.2008.02.033] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2007] [Revised: 02/11/2008] [Accepted: 02/17/2008] [Indexed: 10/22/2022] Open
Abstract
Quantifying change in brain activation patterns associated with post-stroke recovery and reorganization of language function over time requires accurate understanding of inter-scan and inter-subject variability. Here we report inter-scan variability measures for fMRI activation patterns associated with verb generation (VG) and semantic decision/tone decision (SDTD) tasks in 4 healthy controls and 4 aphasic left middle cerebral artery (LMCA) stroke subjects. A series of 10 fMRI scans was completed on a 4T Varian scanner for each task for each subject, except for one stroke subject who completed 5 and 6 scans for SDTD and VG, thus yielding 35 and 36 total stroke subject scans for SDTD and VG, respectively. Group composite and intraclass correlation coefficient (ICC) maps were computed across all subjects and trials for each task. The patterns of reliable activation for the VG and SDTD tasks correspond well to those regions typically activated by these tasks in healthy and aphasic subjects. ICCs for activation were consistently high (R(0.05) approximately 0.8) for individual tasks among both control and aphasic subjects. These voxel-wise measures of reliability highlight regions of low inter-scan variability within language circuitry for control and post-recovery stroke subjects. ICCs computed from the combination of the SDTD/VG data were markedly reduced for both control and aphasic subjects as compared with the ICCs for the individual tasks. These quantitative measures of inter-scan variability support the proposed use of these fMRI paradigms for longitudinal mapping of neural reorganization of language processing following left hemispheric insult.
Collapse
Affiliation(s)
- Kenneth P. Eaton
- Imaging Research Center, Cincinnati Children’s Hospital Research Foundation, Cincinnati, Ohio, U.S.A
| | - Jerzy P. Szaflarski
- Department of Neurology, University of Cincinnati Academic Health Center, Cincinnati, Ohio, U.S.A
- The Neuroscience Institute, Cincinnati, Ohio, U.S.A
- Center for Imaging Research, University of Cincinnati Academic Health Center, Cincinnati, Ohio, U.S.A
| | - Mekibib Altaye
- Imaging Research Center, Cincinnati Children’s Hospital Research Foundation, Cincinnati, Ohio, U.S.A
| | - Angel L. Ball
- Department of Communication Sciences and Disorders, University of Cincinnati, Cincinnati, Ohio, U.S.A
| | - Brett M. Kissela
- Department of Neurology, University of Cincinnati Academic Health Center, Cincinnati, Ohio, U.S.A
- The Neuroscience Institute, Cincinnati, Ohio, U.S.A
| | - Christi Banks
- Department of Neurology, University of Cincinnati Academic Health Center, Cincinnati, Ohio, U.S.A
| | - Scott K. Holland
- Imaging Research Center, Cincinnati Children’s Hospital Research Foundation, Cincinnati, Ohio, U.S.A
- Department of Radiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, U.S.A
| |
Collapse
|
21
|
Schlaug G, Marchina S, Norton A. From Singing to Speaking: Why Singing May Lead to Recovery of Expressive Language Function in Patients with Broca's Aphasia. Music Percept 2008; 25:315-323. [PMID: 21197418 PMCID: PMC3010734 DOI: 10.1525/mp.2008.25.4.315] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
It has been reported that patients with severely nonfluent aphasia are better at singing lyrics than speaking the same words. This observation inspired the development of Melodic Intonation Therapy (MIT), a treatment whose effects have been shown, but whose efficacy is unproven and neural correlates remain unidentified. Because of its potential to engage/unmask language-capable regions in the unaffected right hemisphere, MIT is particularly well suited for patients with large left-hemisphere lesions. Using two patients with similar impairments and stroke size/location, we show the effects of MIT and a control intervention. Both interventions' post-treatment outcomes revealed significant improvement in propositional speech that generalized to unpracticed words and phrases; however, the MIT-treated patient's gains surpassed those of the control-treated patient. Treatment-associated imaging changes indicate that MIT's unique engagement of the right hemisphere, both through singing and tapping with the left hand to prime the sensorimotor and premotor cortices for articulation, accounts for its effect over nonintoned speech therapy.
Collapse
Affiliation(s)
- Gottfried Schlaug
- Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts
| | | | | |
Collapse
|