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Duffau H. Introducing the concept of brain metaplasticity in glioma: how to reorient the pattern of neural reconfiguration to optimize the therapeutic strategy. J Neurosurg 2022; 136:613-617. [PMID: 34624858 DOI: 10.3171/2021.5.jns211214] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Hugues Duffau
- 1Department of Neurosurgery, Gui de Chauliac Hospital, Montpellier University Medical Center; Team "Neuroplasticity, Stem Cells and Glial Tumors," Institute of Functional Genomics, INSERM U-1191, University of Montpellier; and University of Montpellier, France
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52
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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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Watanabe H, Hikida S, Ikeda M, Mori E. OUP accepted manuscript. Brain Commun 2022; 4:fcac015. [PMID: 35686225 PMCID: PMC9171501 DOI: 10.1093/braincomms/fcac015] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 09/07/2021] [Accepted: 01/31/2022] [Indexed: 11/26/2022] Open
Abstract
Primary progressive aphasia, a neurodegenerative syndrome, presents mainly with language impairment. Both semantic and logopenic variants are fluent variants of primary progressive aphasia. Before the research criteria of primary progressive aphasia were proposed, progressive fluent aphasias, such as progressive anomic aphasia, transcortical sensory aphasia and Wernicke’s aphasia, were reported as classical progressive fluent aphasias seen in Alzheimer’s disease. However, since the research criteria of primary progressive aphasia were established, classical fluent variants (other than semantic and logopenic variants) have been neglected and have not been included in the current classification of primary progressive aphasia. This study aimed to determine whether unclassified fluent variants (other than semantic and logopenic variants) can be manifestations of primary progressive aphasia. This study also reconfirmed the characteristics of classical progressive fluent aphasia, such as progressive anomic aphasia, progressive transcortical sensory aphasia and progressive Wernicke’s aphasia as unclassified fluent variants of primary progressive aphasia, using comparison with the current model of primary progressive aphasia. Twelve consecutive patients with an unclassified fluent variant other than semantic or logopenic variant underwent language, neurological, neuropsychological and neuroimaging (MRI and single-photon emission computed tomography) testing. Based on comprehensive language tests, we redefined the diagnoses as primary progressive anomic aphasia (n = 8), primary progressive transcortical sensory aphasia (n = 3) and primary progressive Wernicke’s aphasia (n = 1). Anomic aphasia was characterized by anomia but preserved repetition and comprehension; transcortical sensory aphasia by relatively preserved repetition but poor word comprehension; and Wernicke’s aphasia by poor repetition and word comprehension. In patients with anomic aphasia, voxel-based morphometry of MRI data revealed cortical atrophy, which was most prominent in the temporoparietal lobes, with no obvious lateralization; in two-thirds of patients with transcortical sensory aphasia and in one patient with Wernicke’s aphasia, it revealed atrophy, predominantly in the left temporoparietal lobe. Statistical analysis of single-photon emission computed tomography using three-dimensional stereotactic surface projections revealed patterns of left-sided hypoperfusion in the majority of patients. The temporal and parietal lobes were involved in all cases; the degree of hypoperfusion was higher in patients with transcortical sensory aphasia or Wernicke’s aphasia than in patients with anomic aphasia. The present study demonstrated the clinical and imaging features of 12 patients with an unclassified fluent variant of primary progressive aphasia, which we redefined as primary progressive anomic aphasia, primary progressive transcortical sensory aphasia and primary progressive Wernicke’s aphasia. Classical fluent variants other than semantic and logopenic variants can be found in primary progressive aphasia.
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Affiliation(s)
- Hiroyuki Watanabe
- Correspondence to: Hiroyuki Watanabe Department of Behavioral Neurology and Neuropsychiatry Osaka University United Graduate School of Child Development 2-2, Yamadaoka, Suita Osaka 565-0871, Japan E-mail:
| | - Sakura Hikida
- Department of Psychiatry, Osaka University Graduate School of Medicine, Suita, Japan
- Brain Function Center, Nippon Life Hospital, Osaka, Japan
| | - Manabu Ikeda
- Department of Psychiatry, Osaka University Graduate School of Medicine, Suita, Japan
- Brain Function Center, Nippon Life Hospital, Osaka, Japan
| | - Etsuro Mori
- Department of Behavioral Neurology and Neuropsychiatry, Osaka University United Graduate School of Child Development, Suita, Japan
- Brain Function Center, Nippon Life Hospital, Osaka, Japan
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Zhang C, Xia Y, Feng T, Yu K, Zhang H, Sami MU, Xiang J, Xu K. Disrupted Functional Connectivity Within and Between Resting-State Networks in the Subacute Stage of Post-stroke Aphasia. Front Neurosci 2021; 15:746264. [PMID: 34924929 PMCID: PMC8672309 DOI: 10.3389/fnins.2021.746264] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 11/03/2021] [Indexed: 11/22/2022] Open
Abstract
Background: Post-stroke aphasia (PSA) results from brain network disorders caused by focal stroke lesions. However, it still remains largely unclear whether the impairment is present in intra- and internetwork functional connectivity (FC) within each resting-state network (RSN) and between RSNs in the subacute stage of PSA. Objectives: This study aimed to investigate the resting-state FC within and between RSNs in patients with PSA and observe the relationships between FC alterations and Western Aphasia Battery (WAB) measures. Methods: A total of 20 individuals with subacute PSA and 20 healthy controls (HCs) were recruited for functional MRI (fMRI) scanning, and only patients with PSA underwent WAB assessment. Independent component analysis was carried out to identify RSNs. Two-sample t-tests were used to calculate intra- and internetwork FC differences between patients with PSA and HCs. The results were corrected for multiple comparisons using the false discovery rate (FDR correction, p < 0.05). Partial correlation analysis was performed to observe the relationship between FC and WAB scores with age, gender, mean framewise displacement, and lesion volume as covariates (p < 0.05). Results: Compared to HCs, patients with PSA showed a significant increase in intranetwork FC in the salience network (SN). For internetwork FC analysis, patients showed a significantly increased coupling between left frontoparietal network (lFPN) and SN and decreased coupling between lFPN and right frontoparietal network (rFPN) as well as between lFPN and posterior default mode network (pDMN) (FDR correction, p < 0.05). Finally, a significant positive correlation was found between the intergroup difference of FC (lFPN-rFPN) and auditory-verbal comprehension (p < 0.05). Conclusion: Altered FC was revealed within and between multiple RSNs in patients with PSA at the subacute stage. Reduced FC between lFPN and rFPN was the key element participating in language destruction. These findings proved that PSA is a brain network disorder caused by focal lesions; besides, it may improve our understanding of the pathophysiological mechanisms of patients with PSA at the subacute stage.
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Affiliation(s)
- Chao Zhang
- Department of Radiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Yingying Xia
- Department of Radiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Tao Feng
- Department of Rehabilitation, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Ke Yu
- Department of Radiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Haiyan Zhang
- Department of Radiology, The Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Muhammad Umair Sami
- Department of Radiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Jie Xiang
- Department of Rehabilitation, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Kai Xu
- Department of Radiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
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55
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Linke AC, Slušná D, Kohli JS, Álvarez-Linera Prado J, Müller RA, Hinzen W. Morphometry and functional connectivity of auditory cortex in school-age children with profound language disabilities: Five comparative case studies. Brain Cogn 2021; 155:105822. [PMID: 34837801 DOI: 10.1016/j.bandc.2021.105822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 10/27/2021] [Accepted: 11/02/2021] [Indexed: 10/19/2022]
Abstract
Many neurodevelopmental conditions imply absent or severely reduced language capacities at school age. Evidence from functional magnetic resonance imaging is highly limited. We selected a series of five cases scanned with the same fMRI paradigm and the aim of relating individual language profiles onto underlying patterns of functional connectivity (FC) across auditory language cortex: three with neurogenetic syndromes (Coffin-Siris, Landau-Kleffner, and Fragile-X), one with idiopathic intellectual disability, one with autism spectrum disorder (ASD). Compared to both a group with typical development (TD) and a verbal ASD group (total N = 110), they all showed interhemispheric FC below two standard deviations of the TD mean. Children with higher language scores showed higher intrahemispheric FC between Heschl's gyrus and other auditory language regions, as well as an increase of FC during language stimulation compared to rest. An increase of FC in forward vs. reversed speech in the posterior and middle temporal gyri was seen across all cases. The Coffin-Siris case, the most severe, also had the most anomalous FC patterns and showed reduced myelin content, while the Landau-Kleffner case showed reduced cortical thickness. These results suggest potential for neural markers and mechanisms of severe language processing deficits under highly heterogeneous etiological conditions.
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Affiliation(s)
- Annika Carola Linke
- Brain Development Imaging Laboratories, Department of Psychology, San Diego State University, San Diego, CA, USA.
| | - Dominika Slušná
- Department of Translation and Language Sciences, Campus Poblenou, Pompeu Fabra University, Barcelona 08018, Barcelona, Spain
| | - Jiwandeep Singh Kohli
- Brain Development Imaging Laboratories, Department of Psychology, San Diego State University, San Diego, CA, USA
| | | | - Ralph-Axel Müller
- Brain Development Imaging Laboratories, Department of Psychology, San Diego State University, San Diego, CA, USA; San Diego State University/University of California San Diego Joint Doctoral Program in Clinical Psychology, San Diego, CA, USA
| | - Wolfram Hinzen
- Department of Translation and Language Sciences, Campus Poblenou, Pompeu Fabra University, Barcelona 08018, Barcelona, Spain; Institució Catalana de Recerca i Estudis Avançats, ICREA, 08010 Barcelona, Spain
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56
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Kamaleddin MA. Degeneracy in the nervous system: from neuronal excitability to neural coding. Bioessays 2021; 44:e2100148. [PMID: 34791666 DOI: 10.1002/bies.202100148] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 09/26/2021] [Accepted: 09/28/2021] [Indexed: 02/04/2023]
Abstract
Degeneracy is ubiquitous across biological systems where structurally different elements can yield a similar outcome. Degeneracy is of particular interest in neuroscience too. On the one hand, degeneracy confers robustness to the nervous system and facilitates evolvability: Different elements provide a backup plan for the system in response to any perturbation or disturbance. On the other, a difficulty in the treatment of some neurological disorders such as chronic pain is explained in light of different elements all of which contribute to the pathological behavior of the system. Under these circumstances, targeting a specific element is ineffective because other elements can compensate for this modulation. Understanding degeneracy in the physiological context explains its beneficial role in the robustness of neural circuits. Likewise, understanding degeneracy in the pathological context opens new avenues of discovery to find more effective therapies.
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Affiliation(s)
- Mohammad Amin Kamaleddin
- Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada.,Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, Ontario, Canada
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57
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LaCroix AN, James E, Rogalsky C. Neural Resources Supporting Language Production vs. Comprehension in Chronic Post-stroke Aphasia: A Meta-Analysis Using Activation Likelihood Estimates. Front Hum Neurosci 2021; 15:680933. [PMID: 34759804 PMCID: PMC8572938 DOI: 10.3389/fnhum.2021.680933] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 09/22/2021] [Indexed: 02/04/2023] Open
Abstract
In post-stroke aphasia, language tasks recruit a combination of residual regions within the canonical language network, as well as regions outside of it in the left and right hemispheres. However, there is a lack of consensus as to how the neural resources engaged by language production and comprehension following a left hemisphere stroke differ from one another and from controls. The present meta-analysis used activation likelihood estimates to aggregate across 44 published fMRI and PET studies to characterize the functional reorganization patterns for expressive and receptive language processes in persons with chronic post-stroke aphasia (PWA). Our results in part replicate previous meta-analyses: we find that PWA activate residual regions within the left lateralized language network, regardless of task. Our results extend this work to show differential recruitment of the left and right hemispheres during language production and comprehension in PWA. First, we find that PWA engage left perilesional regions during language comprehension, and that the extent of this activation is likely driven by stimulus type and domain-general cognitive resources needed for task completion. In contrast to comprehension, language production was associated with activation of the right frontal and temporal cortices. Further analyses linked right hemisphere regions involved in motor speech planning for language production with successful naming in PWA, while unsuccessful naming was associated with the engagement of the right inferior frontal gyrus, a region often implicated in domain-general cognitive processes. While the within-group findings indicate that the engagement of the right hemisphere during language tasks in post-stroke aphasia differs for expressive vs. receptive tasks, the overall lack of major between-group differences between PWA and controls implies that PWA rely on similar cognitive-linguistic resources for language as controls. However, more studies are needed that report coordinates for PWA and controls completing the same tasks in order for future meta-analyses to characterize how aphasia affects the neural resources engaged during language, particularly for specific tasks and as a function of behavioral performance.
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Affiliation(s)
- Arianna N LaCroix
- College of Health Sciences, Midwestern University, Glendale, AZ, United States
| | - Eltonnelle James
- College of Health Sciences, Midwestern University, Glendale, AZ, United States
| | - Corianne Rogalsky
- College of Health Solutions, Arizona State University, Tempe, AZ, United States
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58
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Sihvonen AJ, Pitkäniemi A, Leo V, Soinila S, Särkämö T. Resting-state language network neuroplasticity in post-stroke music listening: A randomized controlled trial. Eur J Neurosci 2021; 54:7886-7898. [PMID: 34763370 DOI: 10.1111/ejn.15524] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 10/13/2021] [Accepted: 11/08/2021] [Indexed: 01/31/2023]
Abstract
Recent evidence suggests that post-stroke vocal music listening can aid language recovery, but the network-level functional neuroplasticity mechanisms of this effect are unknown. Here, we sought to determine if improved language recovery observed after post-stroke listening to vocal music is driven by changes in longitudinal resting-state functional connectivity within the language network. Using data from a single-blind randomized controlled trial on stroke patients (N = 38), we compared the effects of daily listening to self-selected vocal music, instrumental music and audio books on changes of the resting-state functional connectivity within the language network and their correlation to improved language skills and verbal memory during the first 3 months post-stroke. From acute to 3-month stage, the vocal music and instrumental music groups increased functional connectivity between a cluster comprising the left inferior parietal areas and the language network more than the audio book group. However, the functional connectivity increase correlated with improved verbal memory only in the vocal music group cluster. This study shows that listening to vocal music post-stroke promotes recovery of verbal memory by inducing changes in longitudinal functional connectivity in the language network. Our results conform to the variable neurodisplacement theory underpinning aphasia recovery.
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Affiliation(s)
- Aleksi J Sihvonen
- Cognitive Brain Research Unit, Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki, Finland.,Centre for Clinical Research, The University of Queensland, Brisbane, Queensland, Australia
| | - Anni Pitkäniemi
- Cognitive Brain Research Unit, Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Vera Leo
- Cognitive Brain Research Unit, Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Seppo Soinila
- Neurocenter, Turku University Hospital and Division of Clinical Neurosciences, University of Turku, Turku, Finland
| | - Teppo Särkämö
- Cognitive Brain Research Unit, Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki, Finland
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59
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Xu S, Yan Z, Pan Y, Yang Q, Liu Z, Gao J, Yang Y, Wu Y, Zhang Y, Wang J, Zhuang R, Li C, Zhang Y, Jia J. Associations between Upper Extremity Motor Function and Aphasia after Stroke: A Multicenter Cross-Sectional Study. Behav Neurol 2021; 2021:9417173. [PMID: 34795804 PMCID: PMC8595012 DOI: 10.1155/2021/9417173] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 10/08/2021] [Accepted: 10/18/2021] [Indexed: 12/21/2022] Open
Abstract
METHODS Patients with stroke were compared and correlated from overall and three periods (1-3 months, 4-6 months, and >6 months). Fugl-Meyer assessment for the upper extremity (FMA-UE) and action research and arm test (ARAT) were used to compare the UE motor status between patients with PSA and without PSA through a cross-sectional study among 435 patients. Then, the correlations between the evaluation scale scores of UE motor status and language function of patients with PSA were analyzed in various dimensions, and the language subfunction most closely related to UE motor function was analyzed by multiple linear regression analysis. RESULTS We found that the scores of FMA-UE and ARAT in patients with PSA were 14 points ((CI) 10 to 18, p < 0.001) and 11 points lower ((CI) 8 to 13, p < 0.001), respectively, than those without PSA. Their FMA-UE (r = 0.70, p < 0.001) and ARAT (r = 0.62, p < 0.001) scores were positively correlated with language function. Regression analysis demonstrated that spontaneous speech ability may account for UE motor function (R 2 = 0.51, p < 0.001; R 2 = 0.42, p < 0.001). Consistent results were also obtained from the analyses within the three time subgroups. CONCLUSION Stroke patients with PSA have worse UE motor performance. UE motor status and language function showed positive correlations, in which spontaneous speech ability significantly accounts for the associations.
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Affiliation(s)
- Shuo Xu
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Zhijie Yan
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
- Xinxiang Medical University, Xinxiang, China
| | - Yongquan Pan
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Qing Yang
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Zhilan Liu
- Department of Rehabilitation Medicine, Shanghai Fourth Rehabilitation Hospital, Shanghai, China
| | - Jiajia Gao
- Department of Neurorehabilitation, The Shanghai Third Rehabilitation Hospital, Shanghai, China
| | - Yanhui Yang
- Department of Rehabilitation Medicine, Shaanxi Provincial Rehabilitation Hospital, Shaanxi, China
| | - Yufen Wu
- Department of Rehabilitation Medicine, Liuzhou Traditional Chinese Medicine Hospital, Guangxi, China
| | - Yanan Zhang
- Department of Rehabilitation Medicine, The Third Affiliated Clinical Hospital of Changchun University of Chinese Medicine, Jilin, China
| | - Jianhui Wang
- Department of Rehabilitation Medicine, Nanshi Hospital Affiliated to Henan University, Henan, China
| | - Ren Zhuang
- Department of Rehabilitation Medicine, Changzhou Dean Hospital, Jiangsu, China
| | - Chong Li
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
- Shanghai University of Sport, Shanghai, China
| | - Yongli Zhang
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
- Fujian University of Traditional Chinese Medicine, Fujian, China
| | - Jie Jia
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
- National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, China
- National Center for Neurological Disorders, Shanghai, China
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60
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Duffau H. The death of localizationism: The concepts of functional connectome and neuroplasticity deciphered by awake mapping, and their implications for best care of brain-damaged patients. Rev Neurol (Paris) 2021; 177:1093-1103. [PMID: 34563375 DOI: 10.1016/j.neurol.2021.07.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2021] [Revised: 06/20/2021] [Accepted: 07/23/2021] [Indexed: 11/28/2022]
Abstract
Although clinical neurology was mainly erected on the dogma of localizationism, numerous reports have described functional recovery after lesions involving presumed non-compensable areas in an inflexible view of brain processing. Here, the purpose is to review new insights into the functional connectome and the mechanisms underpinning neural plasticity, gained from intraoperative direct electrostimulation mapping and real-time behavioral monitoring in awake patients, combined with perioperative neuropsychological and neuroimaging data. Such longitudinal anatomo-functional correlations resulted in the reappraisal of classical models of cognition, especially by highlighting the dynamic interplay within and between neural circuits, leading to the concept of meta-network (network of networks), as well as by emphasizing that subcortical connectivity is the main limitation of neuroplastic potential. Beyond their contribution to basic neurosciences, these findings might also be helpful for an optimization of care for brain-damaged patients, such as in resective oncological or epilepsy neurosurgery in structures traditionally deemed inoperable (e.g., in Broca's area) as well as for elaborating new programs of functional rehabilitation, eventually combined with transcranial brain stimulation, aiming to change the connectivity patterns in order to enhance cognitive competences following cerebral injury.
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Affiliation(s)
- H Duffau
- Department of Neurosurgery, Gui-de-Chauliac Hospital, Montpellier University Medical Center, 80, avenue Augustin-Fliche, 34295 Montpellier, France; National Institute for Health and Medical Research (INSERM), U1191 Laboratory, Team "Brain Plasticity, Stem Cells and Low-Grade Gliomas", Institute of Functional Genomics, University of Montpellier, 34091 Montpellier, France.
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61
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Lwi SJ, Herron TJ, Curran BC, Ivanova MV, Schendel K, Dronkers NF, Baldo JV. Auditory Comprehension Deficits in Post-stroke Aphasia: Neurologic and Demographic Correlates of Outcome and Recovery. Front Neurol 2021; 12:680248. [PMID: 34456845 PMCID: PMC8397517 DOI: 10.3389/fneur.2021.680248] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Accepted: 07/09/2021] [Indexed: 11/30/2022] Open
Abstract
Introduction: One of the most challenging symptoms of aphasia is an impairment in auditory comprehension. The inability to understand others has a direct impact on a person's quality of life and ability to benefit from treatment. Despite its importance, limited research has examined the recovery pattern of auditory comprehension and instead has focused on aphasia recovery more generally. Thus, little is known about the time frame for auditory comprehension recovery following stroke, and whether specific neurologic and demographic variables contribute to recovery and outcome. Methods: This study included 168 left hemisphere chronic stroke patients stroke patients with auditory comprehension impairments ranging from mild to severe. Univariate and multivariate lesion-symptom mapping (LSM) was used to identify brain regions associated with auditory comprehension outcomes on three different tasks: Single-word comprehension, yes/no sentence comprehension, and comprehension of sequential commands. Demographic variables (age, gender, and education) were also examined for their role in these outcomes. In a subset of patients who completed language testing at two or more time points, we also analyzed the trajectory of recovery in auditory comprehension using survival curve-based time compression. Results: LSM analyses revealed that poor single-word auditory comprehension was associated with lesions involving the left mid- to posterior middle temporal gyrus, and portions of the angular and inferior-middle occipital gyri. Poor yes/no sentence comprehension was associated almost exclusively with the left mid-posterior middle temporal gyrus. Poor comprehension of sequential commands was associated with lesions in the left posterior middle temporal gyrus. There was a small region of convergence between the three comprehension tasks, in the very posterior portion of the left middle temporal gyrus. The recovery analysis revealed that auditory comprehension scores continued to improve beyond the first year post-stroke. Higher education was associated with better outcome on all auditory comprehension tasks. Age and gender were not associated with outcome or recovery slopes. Conclusions: The current findings suggest a critical role for the posterior left middle temporal gyrus in the recovery of auditory comprehension following stroke, and that spontaneous recovery of auditory comprehension can continue well beyond the first year post-stroke.
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Affiliation(s)
- Sandy J Lwi
- Veterans Affairs Northern California Health Care System, Martinez, CA, United States
| | - Timothy J Herron
- Veterans Affairs Northern California Health Care System, Martinez, CA, United States
| | - Brian C Curran
- Veterans Affairs Northern California Health Care System, Martinez, CA, United States
| | - Maria V Ivanova
- Department of Psychology, University of California, Berkeley, Berkeley, CA, United States
| | - Krista Schendel
- Veterans Affairs Northern California Health Care System, Martinez, CA, United States
| | - Nina F Dronkers
- Department of Psychology, University of California, Berkeley, Berkeley, CA, United States
| | - Juliana V Baldo
- Veterans Affairs Northern California Health Care System, Martinez, CA, United States
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62
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Szaflarski JP, Nenert R, Allendorfer JB, Martin AN, Amara AW, Griffis JC, Dietz A, Mark VW, Sung VW, Walker HC, Zhou X, Lindsell CJ. Intermittent Theta Burst Stimulation (iTBS) for Treatment of Chronic Post-Stroke Aphasia: Results of a Pilot Randomized, Double-Blind, Sham-Controlled Trial. Med Sci Monit 2021; 27:e931468. [PMID: 34183640 PMCID: PMC8254416 DOI: 10.12659/msm.931468] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Background Research indicates intermittent theta burst stimulation (iTBS) is a potential treatment of post-stroke aphasia. Material/Methods In this double-blind, sham-controlled trial (NCT 01512264) participants were randomized to receive 3 weeks of sham (G0), 1 week of iTBS/2 weeks of sham (G1), 2 weeks of iTBS/1 week of sham (G2), or 3 weeks of iTBS (G3). FMRI localized residual language function in the left hemisphere; iTBS was applied to the maximum fMRI activation in the residual language cortex in the left frontal lobe. FMRI and aphasia testing were conducted pre-treatment, at ≤1 week after completing treatment, and at 3 months follow-up. Results 27/36 participants completed the trial. We compared G0 to each of the individual treatment group and to all iTBS treatment groups combined (G1–3). In individual groups, participants gained (of moderate or large effect sizes; some significant at P<0.05) on the Boston Naming Test (BNT), the Semantic Fluency Test (SFT), and the Aphasia Quotient of the Western Aphasia Battery-Revised (WAB-R AQ). In G1–3, BNT, and SFT improved immediately after treatment, while the WAB-R AQ improved at 3 months. Compared to G0, the other groups showed greater fMRI activation in both hemispheres and non-significant increases in language lateralization to the left hemisphere. Changes in IFG connectivity were noted with iTBS, showing differences between time-points, with some of them correlating with the behavioral measures. Conclusions The results of this pilot trial support the hypothesis that iTBS applied to the ipsilesional hemisphere can improve aphasia and result in cortical plasticity.
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Affiliation(s)
- Jerzy P Szaflarski
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA.,Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Rodolphe Nenert
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jane B Allendorfer
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA.,Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Amber N Martin
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Amy W Amara
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA.,Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Joseph C Griffis
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA.,Department of Psychology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Aimee Dietz
- Department of Communication Sciences and Disorders, University of Cincinnati, Cincinnati, OH, USA
| | - Victor W Mark
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA.,Department of Psychology, University of Alabama at Birmingham, Birmingham, AL, USA.,Department of Physical Medicine and Rehabilitation, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Victor W Sung
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Harrison C Walker
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA.,Department of Physical Medicine and Rehabilitation, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Xiaohua Zhou
- Department of Physical Medicine and Rehabilitation, University of Alabama at Birmingham, Birmingham, AL, USA
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63
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Jung JY, Rice GE, Lambon Ralph MA. The neural bases of resilient semantic system: evidence of variable neuro-displacement in cognitive systems. Brain Struct Funct 2021; 226:1585-1599. [PMID: 33877431 PMCID: PMC8096767 DOI: 10.1007/s00429-021-02272-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 04/02/2021] [Indexed: 01/20/2023]
Abstract
The purpose of this study was to explore an important research goal in cognitive and clinical neuroscience: What are the neurocomputational mechanisms that make cognitive systems "well engineered" and thus resilient across a range of performance demands and to mild levels of perturbation or even damage? A new hypothesis called 'variable neuro-displacement' suggests that cognitive systems are formed with dynamic, spare processing capacity, which balances energy consumption against performance requirements and can be resilient to changes in performance demands. Here, we tested this hypothesis by investigating the neural dynamics of the semantic system by manipulating performance demand. The performance demand was manipulated with two levels of task difficulty (easy vs. hard) in two different ways (stimulus type and response timing). We found that the demanding semantic processing increased regional activity in both the domain-specific semantic representational system (anterior temporal lobe) and the parallel executive control networks (prefrontal, posterior temporal, and parietal regions). Functional connectivity between these regions was also increased during demanding semantic processing and these increases were related to better semantic task performance. Our results suggest that semantic cognition is made resilient by flexible, dynamic changes including increased regional activity and functional connectivity across both domain-specific and domain-general systems. It reveals the intrinsic resilience-related mechanisms of semantic cognition, mimicking alterations caused by perturbation or brain damage. Our findings provide a strong implication that the intrinsic mechanisms of a well-engineered semantic system might be attributed to the compensatory functional alterations in the impaired brain.
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Affiliation(s)
- Je Young Jung
- School of Psychology, University of Nottingham, University Park, Nottingham, NG7 2RD, UK.
| | - Grace E Rice
- MRC Cognition and Brain Science Unit (CBU), University of Cambridge, Cambridge, CB2 7EF, UK
| | - Matthew A Lambon Ralph
- MRC Cognition and Brain Science Unit (CBU), University of Cambridge, Cambridge, CB2 7EF, UK.
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64
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Allendorfer JB, Nenert R, Nair S, Vannest J, Szaflarski JP. Functional Magnetic Resonance Imaging of Language Following Constraint-Induced Aphasia Therapy Primed with Intermittent Theta Burst Stimulation in 13 Patients with Post-Stroke Aphasia. Med Sci Monit 2021; 27:e930100. [PMID: 33970893 PMCID: PMC8120906 DOI: 10.12659/msm.930100] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Background Aphasia is a debilitating consequence of stroke. This study aimed to investigate the role of functional magnetic resonance imaging (fMRI) activation changes during overt language tasks in promoting language improvements following constraint-induced aphasia therapy (CIAT) primed with intermittent theta burst stimulation (iTBS) in 13 patients with aphasia following ischemic stroke. Material/Methods Participants with post-stroke aphasia participated in CIAT primed with iTBS on 10 consecutive weekdays. They also underwent language testing and fMRI while performing overt language tasks at baseline (N=13), immediately post-treatment (N=13), and after 3 months (N=12). Outcome measures were compared between time points, and relationships between changes in language ability and fMRI activation were examined. Results We observed improvements in naming (p<0.001), aphasia symptoms (p=0.038), apraxia of speech symptoms (p=0.040), perception of everyday communicative ability (p=0.001), and the number of spoken words produced during fMRI (p=0.028). Pre- to post-treatment change in naming was negatively correlated with change in right postcentral gyrus activation related to noun-verb associations (rho=−0.554, p=0.0497). Change in aphasia symptoms from immediately after to 3 months post-treatment was negatively correlated with change in bilateral supplementary motor area activation related to verbal encoding (rho=−0.790, p=0.0022). Conclusions Aphasia improvements coupled with fMRI activation changes over time provide support for treatment-induced neuroplasticity with CIAT primed with iTBS. However, a larger randomized sham-controlled study is warranted to confirm our findings and further our understanding of how iTBS can potentiate beneficial effects of language therapy in post-stroke aphasia.
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Affiliation(s)
- Jane B Allendorfer
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Rodolphe Nenert
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Sangeeta Nair
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jennifer Vannest
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Jerzy P Szaflarski
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA.,Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
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65
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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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66
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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: 42] [Impact Index Per Article: 14.0] [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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67
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Rizzolatti G, Fabbri-Destro M, Nuara A, Gatti R, Avanzini P. The role of mirror mechanism in the recovery, maintenance, and acquisition of motor abilities. Neurosci Biobehav Rev 2021; 127:404-423. [PMID: 33910057 DOI: 10.1016/j.neubiorev.2021.04.024] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 03/12/2021] [Accepted: 04/20/2021] [Indexed: 10/21/2022]
Abstract
While it is well documented that the motor system is more than a mere implementer of motor actions, the possible applications of its cognitive side are still under-exploited, often remaining as poorly organized evidence. Here, we will collect evidence showing the value of action observation treatment (AOT) in the recovery of impaired motor abilities for a vast number of clinical conditions, spanning from traumatological patients to brain injuries and neurodegenerative diseases. Alongside, we will discuss the use of AOT in the maintenance of appropriate motor behavior in subjects at risk for events with dramatic physical consequences, like fall prevention in elderly people or injury prevention in sports. Finally, we will report that AOT can help to tune existing motor competencies in fields requiring precise motor control. We will connect all these diverse dots into the neurophysiological scenario offered by decades of research on the human mirror mechanism, discussing the potentialities for individualization. Empowered by modern technologies, AOT can impact individuals' safety and quality of life across the whole lifespan.
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Affiliation(s)
- Giacomo Rizzolatti
- Consiglio Nazionale delle Ricerche, Istituto di Neuroscienze, Parma, Italy
| | | | - Arturo Nuara
- Consiglio Nazionale delle Ricerche, Istituto di Neuroscienze, Parma, Italy; Università di Modena e Reggio Emilia, Dipartimento di Scienze Biomediche, Metaboliche, e Neuroscienze, Modena, Italy
| | - Roberto Gatti
- Istituto Clinico Humanitas, Humanitas Clinical and Research Center, Rozzano, Milan, Italy
| | - Pietro Avanzini
- Consiglio Nazionale delle Ricerche, Istituto di Neuroscienze, Parma, Italy; Istituto Clinico Humanitas, Humanitas Clinical and Research Center, Rozzano, Milan, Italy.
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68
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Herbet G. Should Complex Cognitive Functions Be Mapped With Direct Electrostimulation in Wide-Awake Surgery? A Network Perspective. Front Neurol 2021; 12:635439. [PMID: 33912124 PMCID: PMC8072013 DOI: 10.3389/fneur.2021.635439] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 03/17/2021] [Indexed: 12/18/2022] Open
Affiliation(s)
- Guillaume Herbet
- Institute of Functional Genomics, INSERM, CNRS, University of Montpellier, Montpellier, France.,Gui de Chauliac Hospital, Montpellier University Medical Center, Montpellier, France
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69
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Stefaniak JD, Alyahya RSW, Lambon Ralph MA. Language networks in aphasia and health: A 1000 participant activation likelihood estimation meta-analysis. Neuroimage 2021; 233:117960. [PMID: 33744459 DOI: 10.1016/j.neuroimage.2021.117960] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 02/28/2021] [Accepted: 03/08/2021] [Indexed: 12/20/2022] Open
Abstract
Aphasia recovery post-stroke is classically and most commonly hypothesised to rely on regions that were not involved in language premorbidly, through 'neurocomputational invasion' or engagement of 'quiescent homologues'. Contemporary accounts have suggested, instead, that recovery might be supported by under-utilised areas of the premorbid language network, which are downregulated in health to save neural resources ('variable neurodisplacement'). Despite the importance of understanding the neural bases of language recovery clinically and theoretically, there is no consensus as to which specific regions are more likely to be activated in post-stroke aphasia (PSA) than healthy individuals. Accordingly, we performed an Activation Likelihood Estimation (ALE) meta-analysis of language functional neuroimaging studies in PSA. We obtained coordinate-based functional neuroimaging data for 481 individuals with aphasia following left-hemisphere stroke and 530 linked controls from 33 studies that met predefined inclusion criteria. ALE identified regions of consistent, above-chance spatial convergence of activation, as well as regions of significantly different activation likelihood, between participant groups and language tasks. Overall, these findings dispute the prevailing theory that aphasia recovery involves recruitment of novel right hemisphere territory into the language network post-stroke. Instead, multiple regions throughout both hemispheres were consistently activated during language tasks in both PSA and controls. Regions of the right anterior insula, frontal operculum and inferior frontal gyrus (IFG) pars opercularis were more likely to be activated across all language tasks in PSA than controls. Similar regions were more likely to be activated during higher than lower demand comprehension or production tasks, consistent with them representing enhanced utilisation of spare capacity within right hemisphere executive-control related regions. This provides novel evidence that 'variable neurodisplacement' underlies language network changes that occur post-stroke. Conversely, multiple undamaged regions were less likely to be activated across all language tasks in PSA than controls, including domain-general regions of medial superior frontal and paracingulate cortex, right IFG pars triangularis and temporal pole. These changes might represent functional diaschisis, and demonstrate that there is not global, undifferentiated upregulation of all domain-general neural resources during language in PSA. Such knowledge is essential if we are to design neurobiologically-informed therapeutic interventions to facilitate language recovery.
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Affiliation(s)
- James D Stefaniak
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK; Department of Psychiatry, University of Cambridge, Cambridge, UK; Division of Neuroscience and Experimental Psychology, University of Manchester, Manchester, UK.
| | - Reem S W Alyahya
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK; King Fahad Medical City, Riyadh, Saudi Arabia; Alfaisal University, Riyadh, Saudi Arabia
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70
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Shifting of global aphasia to Wernicke's aphasia in a patient with intact motor function: a case report. BMC Neurol 2021; 21:111. [PMID: 33706719 PMCID: PMC7949244 DOI: 10.1186/s12883-021-02131-w] [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: 11/13/2020] [Accepted: 03/01/2021] [Indexed: 11/17/2022] Open
Abstract
Background Global aphasia without hemiparesis (GAWH) is a rare stroke syndrome characterized by the dissociation of motor and language functions. Here, we present a case of GAWH with the patient later regaining speech fluency. Case presentation A 73-year-old man was admitted to our emergency department immediately after an episode of syncope. On arrival, we noted his global aphasia but without any focal neurologic signs. Computed tomography (CT) perfusion scans showed a large hypodense region over his left perisylvian area. Under the impression of acute ischaemic stroke, he received recombinant tissue plasminogen activator (rtPA) injection and was treated as an inpatient. The patient was later discharged with GAWH status and received regular speech rehabilitation. After 14 months of rehabilitation, the patient gradually recovered his language expression ability. The degree of aphasia was evaluated with the Concise Chinese Aphasia Test (CCAT), and we obtained brain single photon emission computed tomography (SPECT) scans to assess cerebral blood flow. Conclusion A patient with severe impairments of Broca’s and Wernicke’s areas was able to talk fluently despite being unintelligible. SPECT revealed relative high level of radioactivity uptake in the right frontal lobe, suggesting the deficits in speech fluency could have been compensated by the right hemisphere. Although this is a single case demonstration, the results may strengthen the role of the right hemisphere in GAWH patients and suggests additional study that examines the possible benefits of stimulating activity at right homologous regions for recovering language function after global aphasia.
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71
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Dresang HC, Hula WD, Yeh FC, Warren T, Dickey MW. White-Matter Neuroanatomical Predictors of Aphasic Verb Retrieval. Brain Connect 2021; 11:319-330. [PMID: 33470167 DOI: 10.1089/brain.2020.0921] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Background: Current neurocognitive models of language function have been primarily built from evidence regarding object naming, and their hypothesized white-matter circuit mechanisms tend to be coarse grained. Methods: In this cross-sectional, observational study, we used novel correlational tractography to assess the white-matter circuit mechanism behind verb retrieval, measured through action picture-naming performance in adults with chronic aphasia. Results: The analysis identified tracts implicated in current neurocognitive dual-stream models of language function, including the left inferior fronto-occipital fasciculus, inferior longitudinal fasciculus, and arcuate fasciculus. However, the majority of tracts associated with verb retrieval were not ones included in dual-stream models of language function. Instead, they were projection pathways that connect frontal and parietal cortices to subcortical regions associated with motor functions, including the left corticothalamic pathway, frontopontine tract, parietopontine tract, corticostriatal pathway, and corticospinal tract. Conclusions: These results highlight that corticosubcortical projection pathways implicated in motor functions may be importantly related to language function. This finding is consistent with grounded accounts of cognition and may furthermore inform neurocognitive models. Impact statement This study suggests that in addition to traditional dual-stream language fiber tracts, the integrity of projection pathways that connect frontal and parietal cortices to subcortical motor regions may be critically associated with verb-retrieval impairments in adults with aphasia. This finding challenges neurological models of language function.
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Affiliation(s)
- Haley C Dresang
- Department of Communication Science and Disorders, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA.,VA Pittsburgh Healthcare System, Pittsburgh, Pennsylvania, USA
| | - William D Hula
- Department of Communication Science and Disorders, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,VA Pittsburgh Healthcare System, Pittsburgh, Pennsylvania, USA
| | - Fang-Cheng Yeh
- Department of Neurological Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Tessa Warren
- Learning Research and Development Center, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,Department of Psychology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Michael Walsh Dickey
- Department of Communication Science and Disorders, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA.,VA Pittsburgh Healthcare System, Pittsburgh, Pennsylvania, USA
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72
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Sommer CJ, Schäbitz WR. Principles and requirements for stroke recovery science. J Cereb Blood Flow Metab 2021; 41:471-485. [PMID: 33175596 PMCID: PMC7907998 DOI: 10.1177/0271678x20970048] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Revised: 10/03/2020] [Accepted: 10/05/2020] [Indexed: 12/11/2022]
Abstract
The disappointing results in bench-to-bedside translation of neuroprotective strategies caused a certain shift in stroke research towards enhancing the endogenous recovery potential of the brain. One reason for this focus on recovery is the much wider time window for therapeutic interventions which is open for at least several months. Since recently two large clinical studies using d-amphetamine or fluoxetine, respectively, to enhance post-stroke neurological outcome failed again it is a good time for a critical reflection on principles and requirements for stroke recovery science. In principal, stroke recovery science deals with all events from the molecular up to the functional and behavioral level occurring after brain ischemia eventually ending up with any measurable improvement of various clinical parameters. A detailed knowledge of the spontaneously occurring post-ischemic regeneration processes is the indispensable prerequisite for any therapeutic approaches aiming to modify these responses to enhance post-stroke recovery. This review will briefly illuminate the molecular mechanisms of post-ischemic regeneration and the principle possibilities to foster post-stroke recovery. In this context, recent translational approaches are analyzed. Finally, the principal and specific requirements and pitfalls in stroke recovery research as well as potential explanations for translational failures will be discussed.
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Affiliation(s)
- Clemens J Sommer
- Institute of Neuropathology, University Medical Center of the
Johannes Gutenberg-University Mainz, Mainz, Germany
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73
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Almairac F, Deverdun J, Cochereau J, Coget A, Lemaitre AL, Moritz-Gasser S, Duffau H, Herbet G. Homotopic redistribution of functional connectivity in insula-centered diffuse low-grade glioma. Neuroimage Clin 2021; 29:102571. [PMID: 33508623 PMCID: PMC7840474 DOI: 10.1016/j.nicl.2021.102571] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 01/12/2021] [Accepted: 01/13/2021] [Indexed: 12/16/2022]
Abstract
OBJECTIVE In the event of neural injury, the homologous contralateral brain areas may play a compensatory role to avoid or limit the functional loss. However, this dynamic strategy of functional redistribution is not clearly established, especially in the pathophysiological context of diffuse low-grade glioma. Our aim here was to assess the extent to which unilateral tumor infiltration of the insula dynamically modulates the functional connectivity of the contralesional one. METHODS Using resting-state functional connectivity MRI, a seed-to-ROI approach was employed in 52 insula-centered glioma patients (n = 30 left and 22 right) compared with 19 age-matched healthy controls. RESULTS Unsurprisingly, a significant decrease of the inter-insular connectivity was observed in both patient groups. More importantly, the analyses revealed a significant increase of the contralesional insular connectivity towards both cerebral hemispheres, especially in cortical areas forming the visual and the sensorimotor networks. This functional redistribution was not identified when the analyses were performed on three control regions for which the homologous area was not impaired by the tumor. This overall pattern of results indicates that massive infiltration of the insular cortex causes a significant redeployment of the contralesional functional connectivity. CONCLUSION This general finding suggests that the undamaged insula plays a role in the functional compensation usually observed in this patient population, and thus provides compelling support for the concept of homotopic functional plasticity in brain-damaged patients.
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Affiliation(s)
- Fabien Almairac
- Department of Neurosurgery, Pasteur 2 Hospital, Nice University Medical Center, Nice, France; Université Côte d'Azur, Nice, France
| | - Jeremy Deverdun
- I2FH, Institut d'Imagerie Fonctionnelle Humaine, Gui de Chauliac Hospital, Montpellier University Medical Center, Montpellier, France; Department of Neuroradiology, Gui de Chauliac Hospital, Montpellier University Medical Center, Montpellier, France
| | - Jérôme Cochereau
- Department of Neurosurgery, La Miletrie Hospital, Poitiers University Medical Center, Poitiers, France; Institute of Functional Genomics, INSERM 1191, University of Montpellier, France; University of Montpellier, Montpellier, France
| | - Arthur Coget
- I2FH, Institut d'Imagerie Fonctionnelle Humaine, Gui de Chauliac Hospital, Montpellier University Medical Center, Montpellier, France; Department of Neuroradiology, Gui de Chauliac Hospital, Montpellier University Medical Center, Montpellier, France
| | - Anne-Laure Lemaitre
- Department of Neurosurgery, Gui de Chauliac Hospital, Montpellier University Medical Center, Montpellier, France
| | - Sylvie Moritz-Gasser
- Institute of Functional Genomics, INSERM 1191, University of Montpellier, France; University of Montpellier, Montpellier, France; Department of Neurosurgery, Gui de Chauliac Hospital, Montpellier University Medical Center, Montpellier, France
| | - Hugues Duffau
- Institute of Functional Genomics, INSERM 1191, University of Montpellier, France; University of Montpellier, Montpellier, France; Department of Neurosurgery, Gui de Chauliac Hospital, Montpellier University Medical Center, Montpellier, France
| | - Guillaume Herbet
- Institute of Functional Genomics, INSERM 1191, University of Montpellier, France; University of Montpellier, Montpellier, France; Department of Neurosurgery, Gui de Chauliac Hospital, Montpellier University Medical Center, Montpellier, France.
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74
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Wilson SM, Schneck SM. Neuroplasticity in post-stroke aphasia: A systematic review and meta-analysis of functional imaging studies of reorganization of language processing. NEUROBIOLOGY OF LANGUAGE (CAMBRIDGE, MASS.) 2021; 2:22-82. [PMID: 33884373 PMCID: PMC8057712 DOI: 10.1162/nol_a_00025] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2023]
Abstract
Recovery from aphasia is thought to depend on neural plasticity, that is, functional reorganization of surviving brain regions such that they take on new or expanded roles in language processing. We carried out a systematic review and meta-analysis of all articles published between 1995 and early 2020 that have described functional imaging studies of six or more individuals with post-stroke aphasia, and have reported analyses bearing on neuroplasticity of language processing. Each study was characterized and appraised in detail, with particular attention to three critically important methodological issues: task performance confounds, contrast validity, and correction for multiple comparisons. We identified 86 studies describing a total of 561 relevant analyses. We found that methodological limitations related to task performance confounds, contrast validity, and correction for multiple comparisons have been pervasive. Only a few claims about language processing in individuals with aphasia are strongly supported by the extant literature: first, left hemisphere language regions are less activated in individuals with aphasia than neurologically normal controls, and second, in cohorts with aphasia, activity in left hemisphere language regions, and possibly a temporal lobe region in the right hemisphere, is positively correlated with language function. There is modest, equivocal evidence for the claim that individuals with aphasia differentially recruit right hemisphere homotopic regions, but no compelling evidence for differential recruitment of additional left hemisphere regions or domain-general networks. There is modest evidence that left hemisphere language regions return to function over time, but no compelling longitudinal evidence for dynamic reorganization of the language network.
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Affiliation(s)
- Stephen M. Wilson
- Address for correspondence: Stephen M. Wilson, Department of Hearing and Speech Sciences, Vanderbilt University Medical Center, 1215 21st Ave S, MCE 8310, Nashville, TN 37232. Phone: 615-936-5810.
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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; 117:32779-32790. [PMID: 33273118 PMCID: PMC7768768 DOI: 10.1073/pnas.2010193117] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [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.
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76
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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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77
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Duffau H. Functional Mapping before and after Low-Grade Glioma Surgery: A New Way to Decipher Various Spatiotemporal Patterns of Individual Neuroplastic Potential in Brain Tumor Patients. Cancers (Basel) 2020; 12:E2611. [PMID: 32933174 PMCID: PMC7565450 DOI: 10.3390/cancers12092611] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 09/07/2020] [Accepted: 09/11/2020] [Indexed: 12/21/2022] Open
Abstract
Intraoperative direct electrostimulation mapping (DEM) is currently the gold-standard for glioma surgery, since functional-based resection allows an optimization of the onco-functional balance (increased resection with preserved quality of life). Besides intrasurgical awake mapping of conation, cognition, and behavior, preoperative mapping by means of functional neuroimaging (FNI) and transcranial magnetic stimulation (TMS) has increasingly been utilized for surgical selection and planning. However, because these techniques suffer from several limitations, particularly for direct functional mapping of subcortical white matter pathways, DEM remains crucial to map neural connectivity. On the other hand, non-invasive FNI and TMS can be repeated before and after surgical resection(s), enabling longitudinal investigation of brain reorganization, especially in slow-growing tumors like low-grade gliomas. Indeed, these neoplasms generate neuroplastic phenomena in patients with usually no or only slight neurological deficits at diagnosis, despite gliomas involving the so-called "eloquent" structures. Here, data gained from perioperative FNI/TMS mapping methods are reviewed, in order to decipher mechanisms underpinning functional cerebral reshaping induced by the tumor and its possible relapse, (re)operation(s), and postoperative rehabilitation. Heterogeneous spatiotemporal patterns of rearrangement across patients and in a single patient over time have been evidenced, with structural changes as well as modifications of intra-hemispheric (in the ipsi-lesional and/or contra-lesional hemisphere) and inter-hemispheric functional connectivity. Such various fingerprints of neural reconfiguration were correlated to different levels of cognitive compensation. Serial multimodal studies exploring neuroplasticity might lead to new management strategies based upon multistage therapeutic approaches adapted to the individual profile of functional reallocation.
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Affiliation(s)
- Hugues Duffau
- Department of Neurosurgery, Montpellier University Medical Center, 34295 Montpellier, France; ; Tel.: +33-4-67-33-66-12; Fax: +33-4-67-33-69-12
- Institute of Functional Genomics, INSERM U-1191, University of Montpellier, 34298 Montpellier, France
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78
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Cortical Reorganization after Rehabilitation in a Patient with Conduction Aphasia Using High-Density EEG. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10155281] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Conduction aphasia is a language disorder occurred after a left-brain injury. It is characterized by fluent speech production, reading, writing and normal comprehension, while speech repetition is impaired. The aim of this study is to investigate the cortical responses, induced by language activities, in a sub-acute stroke patient affected by conduction aphasia before and after an intensive speech therapy training. The patient was examined by using High-Density Electroencephalogram (HD-EEG) examination, while was performing language tasks. the patient was evaluated at baseline and after two months after rehabilitative treatment. Our results showed that an intensive rehabilitative process, in sub-acute stroke, could be useful for a good outcome of language deficits. HD-EEG results showed that left parieto-temporol-frontal areas were more activated after 2 months of rehabilitation training compared with baseline. Our results provided evidence that an intensive rehabilitation process could contribute to an inter- and intra-hemispheric reorganization.
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79
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Repetitive transcranial magnetic stimulation as an alternative therapy for stroke with spasticity: a systematic review and meta-analysis. J Neurol 2020; 268:4013-4022. [PMID: 32654060 DOI: 10.1007/s00415-020-10058-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 07/03/2020] [Accepted: 07/04/2020] [Indexed: 10/23/2022]
Abstract
Repetitive transcranial magnetic stimulation (rTMS) and intermittent theta-burst stimulation (iTBS) can be used to manage post-stroke spasticity, but a meta-analysis of the recent randomized-controlled trials (RCTs) is lacking. Our aim is to perform a meta-analysis of the RCTs that investigated the efficacy of rTMS in patients with post-stroke spasticity. PubMed, Embase, and Cochrane Library databases were searched for eligible papers published up to February 2020. The primary outcome was the Modified Ashworth Scale (MAS), measured as the effect of rTMS compared with controls and after rTMS (using a change score calculated separately in the active and sham treatment groups). Finally, five papers and eight data sets were included. rTMS had no significant benefit on MAS in patients with post-stroke spasticity compared to sham treatment (WMD = - 0.29, 95% CI - 0.58, 0.00; P = 0.051). When analyzing the change score in the treatment groups, a significant effect of rTMS was observed (WMD = - 0.27, 95% CI - 0.51, - 0.04; P = 0.024). When analyzing the change score in the sham treatment groups, no significant effect of sham treatment was observed, indicating no placebo effect (WMD = 0.32, 95% CI: - 0.40, 1.04; P = 0.387). We included the sample size, year of publication, percentage of male patients, and age difference in each study as covariates, and performed a meta-regression. The results showed no association between these variables and the MAS. Compared with sham stimulation, rTMS did not show a significant reduction in MAS for the patients who experienced post-stroke spasticity, but the patients reported a better outcome in MAS on a before-after scenario.
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80
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Berthier ML, Dávila G, Torres-Prioris MJ, Moreno-Torres I, Clarimón J, Dols-Icardo O, Postigo MJ, Fernández V, Edelkraut L, Moreno-Campos L, Molina-Sánchez D, de Zaldivar PS, López-Barroso D. Developmental Dynamic Dysphasia: Are Bilateral Brain Abnormalities a Signature of Inefficient Neural Plasticity? Front Hum Neurosci 2020; 14:73. [PMID: 32265672 DOI: 10.3389/fnhum.2020.00073] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 02/19/2020] [Indexed: 12/30/2022] Open
Abstract
The acquisition and evolution of speech production, discourse and communication can be negatively impacted by brain malformations. We describe, for the first time, a case of developmental dynamic dysphasia (DDD) in a right-handed adolescent boy (subject D) with cortical malformations involving language-eloquent regions (inferior frontal gyrus) in both the left and the right hemispheres. Language evaluation revealed a markedly reduced verbal output affecting phonemic and semantic fluency, phrase and sentence generation and verbal communication in everyday life. Auditory comprehension, repetition, naming, reading and spelling were relatively preserved, but executive function was impaired. Multimodal neuroimaging showed a malformed cerebral cortex with atypical configuration and placement of white matter tracts bilaterally and abnormal callosal fibers. Dichotic listening showed right hemisphere dominance for language, and functional magnetic resonance imaging (fMRI) additionally revealed dissociated hemispheric language representation with right frontal activation for phonology and bilateral dominance for semantic processing. Moreover, subject D also had congenital mirror movements (CMM), defined as involuntary movements of one side of the body that mirror intentional movements of the other side. Transcranial magnetic stimulation and fMRI during voluntary unimanual (left and right) hand movements showed bilateral motor cortex recruitment and tractography revealed a lack of decussation of bilateral corticospinal tracts. Genetic testing aimed to detect mutations that disrupt the development of commissural tracts correlating with CMM (e.g., Germline DCC mutations) was negative. Overall, our findings suggest that DDD in subject D resulted from the underdevelopment of the left inferior frontal gyrus with limited capacity for plastic reorganization by its homologous counterpart in the right hemisphere. Corpus callosum anomalies probably contributed to hinder interhemispheric connectivity necessary to compensate language and communication deficits after left frontal involvement.
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Affiliation(s)
- Marcelo L Berthier
- Cognitive Neurology and Aphasia Unit, Centro de Investigaciones Médico-Sanitarias, Instituto de Investigación Biomédica de Málaga (IBIMA), University of Malaga, Málaga, Spain
| | - Guadalupe Dávila
- Cognitive Neurology and Aphasia Unit, Centro de Investigaciones Médico-Sanitarias, Instituto de Investigación Biomédica de Málaga (IBIMA), University of Malaga, Málaga, Spain.,Department of Psychobiology and Methodology of Behavioral Sciences, Faculty of Psychology, University of Malaga, Málaga, Spain
| | - María José Torres-Prioris
- Cognitive Neurology and Aphasia Unit, Centro de Investigaciones Médico-Sanitarias, Instituto de Investigación Biomédica de Málaga (IBIMA), University of Malaga, Málaga, Spain.,Department of Psychobiology and Methodology of Behavioral Sciences, Faculty of Psychology, University of Malaga, Málaga, Spain
| | | | - Jordi Clarimón
- Department of Neurology and Sant Pau Biomedical Research Institute, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain.,Center for Networked Biomedical Research into Neurodegenerative Diseases, Madrid, Spain
| | - Oriol Dols-Icardo
- Department of Neurology and Sant Pau Biomedical Research Institute, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain.,Center for Networked Biomedical Research into Neurodegenerative Diseases, Madrid, Spain
| | - María J Postigo
- Neurophysiology Unit, Regional University Hospital Carlos Haya, Málaga, Spain
| | - Victoria Fernández
- Neurophysiology Unit, Regional University Hospital Carlos Haya, Málaga, Spain
| | - Lisa Edelkraut
- Cognitive Neurology and Aphasia Unit, Centro de Investigaciones Médico-Sanitarias, Instituto de Investigación Biomédica de Málaga (IBIMA), University of Malaga, Málaga, Spain.,Department of Psychobiology and Methodology of Behavioral Sciences, Faculty of Psychology, University of Malaga, Málaga, Spain
| | - Lorena Moreno-Campos
- Cognitive Neurology and Aphasia Unit, Centro de Investigaciones Médico-Sanitarias, Instituto de Investigación Biomédica de Málaga (IBIMA), University of Malaga, Málaga, Spain
| | - Diana Molina-Sánchez
- Cognitive Neurology and Aphasia Unit, Centro de Investigaciones Médico-Sanitarias, Instituto de Investigación Biomédica de Málaga (IBIMA), University of Malaga, Málaga, Spain
| | - Paloma Solo de Zaldivar
- Cognitive Neurology and Aphasia Unit, Centro de Investigaciones Médico-Sanitarias, Instituto de Investigación Biomédica de Málaga (IBIMA), University of Malaga, Málaga, Spain
| | - Diana López-Barroso
- Cognitive Neurology and Aphasia Unit, Centro de Investigaciones Médico-Sanitarias, Instituto de Investigación Biomédica de Málaga (IBIMA), University of Malaga, Málaga, Spain.,Department of Psychobiology and Methodology of Behavioral Sciences, Faculty of Psychology, University of Malaga, Málaga, Spain
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