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Billot A, Kiran S. Disentangling neuroplasticity mechanisms in post-stroke language recovery. BRAIN AND LANGUAGE 2024; 251:105381. [PMID: 38401381 PMCID: PMC10981555 DOI: 10.1016/j.bandl.2024.105381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 11/28/2023] [Accepted: 01/12/2024] [Indexed: 02/26/2024]
Abstract
A major objective in post-stroke aphasia research is to gain a deeper understanding of neuroplastic mechanisms that drive language recovery, with the ultimate goal of enhancing treatment outcomes. Subsequent to recent advances in neuroimaging techniques, we now have the ability to examine more closely how neural activity patterns change after a stroke. However, the way these neural activity changes relate to language impairments and language recovery is still debated. The aim of this review is to provide a theoretical framework to better investigate and interpret neuroplasticity mechanisms underlying language recovery in post-stroke aphasia. We detail two sets of neuroplasticity mechanisms observed at the synaptic level that may explain functional neuroimaging findings in post-stroke aphasia recovery at the network level: feedback-based homeostatic plasticity and associative Hebbian plasticity. In conjunction with these plasticity mechanisms, higher-order cognitive control processes dynamically modulate neural activity in other regions to meet communication demands, despite reduced neural resources. This work provides a network-level neurobiological framework for understanding neural changes observed in post-stroke aphasia and can be used to define guidelines for personalized treatment development.
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Affiliation(s)
- Anne Billot
- Center for Brain Recovery, Boston University, Boston, USA; Department of Psychology, Center for Brain Science, Harvard University, Cambridge, Massachusetts, USA; Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Swathi Kiran
- Center for Brain Recovery, Boston University, Boston, USA.
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2
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Lei VLC, Leong TI, Leong CT, Liu L, Choi CU, Sereno MI, Li D, Huang R. Phase-encoded fMRI tracks down brainstorms of natural language processing with subsecond precision. Hum Brain Mapp 2024; 45:e26617. [PMID: 38339788 PMCID: PMC10858339 DOI: 10.1002/hbm.26617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 12/04/2023] [Accepted: 01/21/2024] [Indexed: 02/12/2024] Open
Abstract
Natural language processing unfolds information overtime as spatially separated, multimodal, and interconnected neural processes. Existing noninvasive subtraction-based neuroimaging techniques cannot simultaneously achieve the spatial and temporal resolutions required to visualize ongoing information flows across the whole brain. Here we have developed rapid phase-encoded designs to fully exploit the temporal information latent in functional magnetic resonance imaging data, as well as overcoming scanner noise and head-motion challenges during overt language tasks. We captured real-time information flows as coherent hemodynamic waves traveling over the cortical surface during listening, reading aloud, reciting, and oral cross-language interpreting tasks. We were able to observe the timing, location, direction, and surge of traveling waves in all language tasks, which were visualized as "brainstorms" on brain "weather" maps. The paths of hemodynamic traveling waves provide direct evidence for dual-stream models of the visual and auditory systems as well as logistics models for crossmodal and cross-language processing. Specifically, we have tracked down the step-by-step processing of written or spoken sentences first being received and processed by the visual or auditory streams, carried across language and domain-general cognitive regions, and finally delivered as overt speeches monitored through the auditory cortex, which gives a complete picture of information flows across the brain during natural language functioning. PRACTITIONER POINTS: Phase-encoded fMRI enables simultaneous imaging of high spatial and temporal resolution, capturing continuous spatiotemporal dynamics of the entire brain during real-time overt natural language tasks. Spatiotemporal traveling wave patterns provide direct evidence for constructing comprehensive and explicit models of human information processing. This study unlocks the potential of applying rapid phase-encoded fMRI to indirectly track the underlying neural information flows of sequential sensory, motor, and high-order cognitive processes.
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Affiliation(s)
- Victoria Lai Cheng Lei
- Centre for Cognitive and Brain SciencesUniversity of MacauTaipaChina
- Faculty of Arts and HumanitiesUniversity of MacauTaipaChina
| | - Teng Ieng Leong
- Centre for Cognitive and Brain SciencesUniversity of MacauTaipaChina
- Faculty of Arts and HumanitiesUniversity of MacauTaipaChina
| | - Cheok Teng Leong
- Centre for Cognitive and Brain SciencesUniversity of MacauTaipaChina
- Faculty of Science and TechnologyUniversity of MacauTaipaChina
| | - Lili Liu
- Centre for Cognitive and Brain SciencesUniversity of MacauTaipaChina
- Faculty of Science and TechnologyUniversity of MacauTaipaChina
| | - Chi Un Choi
- Centre for Cognitive and Brain SciencesUniversity of MacauTaipaChina
| | - Martin I. Sereno
- Department of PsychologySan Diego State UniversitySan DiegoCaliforniaUSA
| | - Defeng Li
- Centre for Cognitive and Brain SciencesUniversity of MacauTaipaChina
- Faculty of Arts and HumanitiesUniversity of MacauTaipaChina
| | - Ruey‐Song Huang
- Centre for Cognitive and Brain SciencesUniversity of MacauTaipaChina
- Faculty of Science and TechnologyUniversity of MacauTaipaChina
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3
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Dai Z, Song L, Luo C, Liu D, Li M, Han Z. Hemispheric lateralization of language processing: insights from network-based symptom mapping and patient subgroups. Cereb Cortex 2024; 34:bhad437. [PMID: 38031356 DOI: 10.1093/cercor/bhad437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Revised: 10/27/2023] [Accepted: 10/27/2023] [Indexed: 12/01/2023] Open
Abstract
The hemispheric laterality of language processing has become a hot topic in modern neuroscience. Although most previous studies have reported left-lateralized language processing, other studies found it to be bilateral. A previous neurocomputational model has proposed a unified framework to explain that the above discrepancy might be from healthy and patient individuals. This model posits an initial symmetry but imbalanced capacity in language processing for healthy individuals, with this imbalance contributing to language recovery disparities following different hemispheric injuries. The present study investigated this model by analyzing the lateralization patterns of language subnetworks across multiple attributes with a group of 99 patients (compared to nonlanguage processing) and examining the lateralization patterns of language subnetworks in subgroups with damage to different hemispheres. Subnetworks were identified using a whole-brain network-based lesion-symptom mapping method, and the lateralization index was quantitatively measured. We found that all the subnetworks in language processing were left-lateralized, while subnetworks in nonlanguage processing had different lateralization patterns. Moreover, diverse hemisphere-injury subgroups exhibited distinct language recovery effects. These findings provide robust support for the proposed neurocomputational model of language processing.
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Affiliation(s)
- Zhiyun Dai
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, China
| | - Luping Song
- Shenzhen Sixth People's Hospital (Nanshan Hospital), Huazhong University of Science and Technology Union Shenzhen Hospital, Shenzhen 518052, China
| | - Chongjing Luo
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, China
| | - Di Liu
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, China
| | - Mingyang Li
- Key Laboratory for Biomedical Engineering of Ministry of Education, Department of Biomedical Engineering, College of Biomedical Engineering & Instrument Science, Zhejiang University, Yuquan Campus, Hangzhou 310027, China
| | - Zaizhu Han
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, China
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4
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Vadinova V, Sihvonen AJ, Wee F, Garden KL, Ziraldo L, Roxbury T, O'Brien K, Copland DA, McMahon KL, Brownsett SLE. The volume and the distribution of premorbid white matter hyperintensities: Impact on post-stroke aphasia. Hum Brain Mapp 2024; 45:e26568. [PMID: 38224539 PMCID: PMC10789210 DOI: 10.1002/hbm.26568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 11/29/2023] [Accepted: 12/04/2023] [Indexed: 01/17/2024] Open
Abstract
White matter hyperintensities (WMH) are a radiological manifestation of progressive white matter integrity loss. The total volume and distribution of WMH within the corpus callosum have been associated with pathological cognitive ageing processes but have not been considered in relation to post-stroke aphasia outcomes. We investigated the contribution of both the total volume of WMH, and the extent of WMH lesion load in the corpus callosum to the recovery of language after first-ever stroke. Behavioural and neuroimaging data from individuals (N = 37) with a left-hemisphere stroke were included at the early subacute stage of recovery. Spoken language comprehension and production abilities were assessed using word and sentence-level tasks. Neuroimaging data was used to derive stroke lesion variables (volume and lesion load to language critical regions) and WMH variables (WMH volume and lesion load to three callosal segments). WMH volume did not predict variance in language measures, when considered together with stroke lesion and demographic variables. However, WMH lesion load in the forceps minor segment of the corpus callosum explained variance in early subacute comprehension abilities (t = -2.59, p = .01) together with corrected stroke lesion volume and socio-demographic variables. Premorbid WMH lesions in the forceps minor were negatively associated with early subacute language comprehension after aphasic stroke. This negative impact of callosal WMH on language is consistent with converging evidence from pathological ageing suggesting that callosal WMH disrupt the neural networks supporting a range of cognitive functions.
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Affiliation(s)
- Veronika Vadinova
- Queensland Aphasia Research CentreUniversity of QueenslandBrisbaneAustralia
- School of Health and Rehabilitation SciencesUniversity of QueenslandBrisbaneAustralia
- Centre of Research Excellence in Aphasia Recovery and RehabilitationLa Trobe UniversityMelbourneAustralia
| | - A. J. Sihvonen
- Queensland Aphasia Research CentreUniversity of QueenslandBrisbaneAustralia
- School of Health and Rehabilitation SciencesUniversity of QueenslandBrisbaneAustralia
- Centre of Research Excellence in Aphasia Recovery and RehabilitationLa Trobe UniversityMelbourneAustralia
- Cognitive Brain Research Unit (CBRU)University of HelsinkiHelsinkiFinland
- Centre of Excellence in Music, Mind, Body and BrainUniversity of HelsinkiHelsinkiFinland
| | - F. Wee
- Queensland Aphasia Research CentreUniversity of QueenslandBrisbaneAustralia
| | - K. L. Garden
- Queensland Aphasia Research CentreUniversity of QueenslandBrisbaneAustralia
- School of Health and Rehabilitation SciencesUniversity of QueenslandBrisbaneAustralia
- Centre of Research Excellence in Aphasia Recovery and RehabilitationLa Trobe UniversityMelbourneAustralia
| | - L. Ziraldo
- Queensland Aphasia Research CentreUniversity of QueenslandBrisbaneAustralia
| | - T. Roxbury
- Queensland Aphasia Research CentreUniversity of QueenslandBrisbaneAustralia
| | - K. O'Brien
- Queensland Aphasia Research CentreUniversity of QueenslandBrisbaneAustralia
| | - D. A. Copland
- Queensland Aphasia Research CentreUniversity of QueenslandBrisbaneAustralia
- School of Health and Rehabilitation SciencesUniversity of QueenslandBrisbaneAustralia
- Centre of Research Excellence in Aphasia Recovery and RehabilitationLa Trobe UniversityMelbourneAustralia
| | - K. L. McMahon
- School of Clinical Sciences, Centre for Biomedical TechnologiesQueensland University of TechnologyBrisbaneAustralia
| | - S. L. E. Brownsett
- Queensland Aphasia Research CentreUniversity of QueenslandBrisbaneAustralia
- School of Health and Rehabilitation SciencesUniversity of QueenslandBrisbaneAustralia
- Centre of Research Excellence in Aphasia Recovery and RehabilitationLa Trobe UniversityMelbourneAustralia
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5
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Abstract
Neurological insults, such as congenital blindness, deafness, amputation, and stroke, often result in surprising and impressive behavioural changes. Cortical reorganisation, which refers to preserved brain tissue taking on a new functional role, is often invoked to account for these behavioural changes. Here, we revisit many of the classical animal and patient cortical remapping studies that spawned this notion of reorganisation. We highlight empirical, methodological, and conceptual problems that call this notion into doubt. We argue that appeal to the idea of reorganisation is attributable in part to the way that cortical maps are empirically derived. Specifically, cortical maps are often defined based on oversimplified assumptions of 'winner-takes-all', which in turn leads to an erroneous interpretation of what it means when these maps appear to change. Conceptually, remapping is interpreted as a circuit receiving novel input and processing it in a way unrelated to its original function. This implies that neurons are either pluripotent enough to change what they are tuned to or that a circuit can change what it computes. Instead of reorganisation, we argue that remapping is more likely to occur due to potentiation of pre-existing architecture that already has the requisite representational and computational capacity pre-injury. This architecture can be facilitated via Hebbian and homeostatic plasticity mechanisms. Crucially, our revised framework proposes that opportunities for functional change are constrained throughout the lifespan by the underlying structural 'blueprint'. At no period, including early in development, does the cortex offer structural opportunities for functional pluripotency. We conclude that reorganisation as a distinct form of cortical plasticity, ubiquitously evoked with words such as 'take-over'' and 'rewiring', does not exist.
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Affiliation(s)
- Tamar R Makin
- MRC Cognition and Brain Sciences Unit, University of CambridgeCambridgeUnited Kingdom
| | - John W Krakauer
- Department of Neuroscience, Johns Hopkins University School of MedicineBaltimoreUnited States
- Department of Neurology, Johns Hopkins University School of MedicineBaltimoreUnited States
- The Santa Fe InstituteSanta FeUnited States
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6
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Lei VLC, Leong TI, Leong CT, Liu L, Choi CU, Sereno MI, Li D, Huang RS. Phase-encoded fMRI tracks down brainstorms of natural language processing with sub-second precision. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.29.542546. [PMID: 37398177 PMCID: PMC10312422 DOI: 10.1101/2023.05.29.542546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
The human language system interacts with cognitive and sensorimotor regions during natural language processing. However, where, when, and how these processes occur remain unclear. Existing noninvasive subtraction-based neuroimaging techniques cannot simultaneously achieve the spatial and temporal resolutions required to visualize ongoing information flows across the whole brain. Here we have developed phase-encoded designs to fully exploit the temporal information latent in functional magnetic resonance imaging (fMRI) data, as well as overcoming scanner noise and head-motion challenges during overt language tasks. We captured neural information flows as coherent waves traveling over the cortical surface during listening, reciting, and oral cross-language interpreting. The timing, location, direction, and surge of traveling waves, visualized as 'brainstorms' on brain 'weather' maps, reveal the functional and effective connectivity of the brain in action. These maps uncover the functional neuroanatomy of language perception and production and motivate the construction of finer-grained models of human information processing.
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Affiliation(s)
| | - Teng Ieng Leong
- Centre for Cognitive and Brain Sciences, University of Macau, Taipa, Macau SAR, China
| | - Cheok Teng Leong
- Centre for Cognitive and Brain Sciences, University of Macau, Taipa, Macau SAR, China
| | - Lili Liu
- Centre for Cognitive and Brain Sciences, University of Macau, Taipa, Macau SAR, China
| | - Chi Un Choi
- Centre for Cognitive and Brain Sciences, University of Macau, Taipa, Macau SAR, China
| | - Martin I. Sereno
- Department of Psychology, San Diego State University, San Diego, CA, United States
| | - Defeng Li
- Centre for Cognitive and Brain Sciences, University of Macau, Taipa, Macau SAR, China
| | - Ruey-Song Huang
- Centre for Cognitive and Brain Sciences, University of Macau, Taipa, Macau SAR, China
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7
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Zhao Y, Cox CR, Lambon Ralph MA, Halai AD. Using in vivo functional and structural connectivity to predict chronic stroke aphasia deficits. Brain 2023; 146:1950-1962. [PMID: 36346107 PMCID: PMC10151190 DOI: 10.1093/brain/awac388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 09/11/2022] [Accepted: 09/20/2022] [Indexed: 11/10/2022] Open
Abstract
Focal brain damage caused by stroke can result in aphasia and advances in cognitive neuroscience suggest that impairment may be associated with network-level disorder rather than just circumscribed cortical damage. Several studies have shown meaningful relationships between brain-behaviour using lesions; however, only a handful of studies have incorporated in vivo structural and functional connectivity. Patients with chronic post-stroke aphasia were assessed with structural (n = 68) and functional (n = 39) MRI to assess whether predicting performance can be improved with multiple modalities and if additional variance can be explained compared to lesion models alone. These neural measurements were used to construct models to predict four key language-cognitive factors: (i) phonology; (ii) semantics; (iii) executive function; and (iv) fluency. Our results showed that each factor (except executive ability) could be significantly related to each neural measurement alone; however, structural and functional connectivity models did not explain additional variance above the lesion models. We did find evidence that the structural and functional predictors may be linked to the core lesion sites. First, the predictive functional connectivity features were found to be located within functional resting-state networks identified in healthy controls, suggesting that the result might reflect functionally specific reorganization (damage to a node within a network can result in disruption to the entire network). Second, predictive structural connectivity features were located within core lesion sites, suggesting that multimodal information may be redundant in prediction modelling. In addition, we observed that the optimum sparsity within the regularized regression models differed for each behavioural component and across different imaging features, suggesting that future studies should consider optimizing hyperparameters related to sparsity per target. Together, the results indicate that the observed network-level disruption was predicted by the lesion alone and does not significantly improve model performance in predicting the profile of language impairment.
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Affiliation(s)
- Ying Zhao
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK
- Department of Psychiatry, University of Cambridge, Cambridge, UK
| | - Christopher R Cox
- Department of Psychology, Louisiana State University, Baton Rouge, LA, USA
| | | | - Ajay D Halai
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK
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8
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Jung J, Lambon Ralph MA. Distinct but cooperating brain networks supporting semantic cognition. Cereb Cortex 2023; 33:2021-2036. [PMID: 35595542 PMCID: PMC9977382 DOI: 10.1093/cercor/bhac190] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 04/25/2022] [Accepted: 04/07/2022] [Indexed: 02/02/2023] Open
Abstract
Semantic cognition is a complex multifaceted brain function involving multiple processes including sensory, semantic, and domain-general cognitive systems. However, it remains unclear how these systems cooperate with each other to achieve effective semantic cognition. Here, we used independent component analysis (ICA) to investigate the functional brain networks that support semantic cognition. We used a semantic judgment task and a pattern-matching control task, each with 2 levels of difficulty, to disentangle task-specific networks from domain-general networks. ICA revealed 2 task-specific networks (the left-lateralized semantic network [SN] and a bilateral, extended semantic network [ESN]) and domain-general networks including the frontoparietal network (FPN) and default mode network (DMN). SN was coupled with the ESN and FPN but decoupled from the DMN, whereas the ESN was synchronized with the FPN alone and did not show a decoupling with the DMN. The degree of decoupling between the SN and DMN was associated with semantic task performance, with the strongest decoupling for the poorest performing participants. Our findings suggest that human higher cognition is achieved by the multiple brain networks, serving distinct and shared cognitive functions depending on task demands, and that the neural dynamics between these networks may be crucial for efficient semantic cognition.
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Affiliation(s)
- JeYoung Jung
- School of Psychology, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Matthew A Lambon Ralph
- MRC Cognition and Brain Science Unit (CBU), University of Cambridge, Cambridge, CB2 7EF United Kingdom
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Sander K, Chai X, Barbeau EB, Kousaie S, Petrides M, Baum S, Klein D. Interhemispheric functional brain connectivity predicts new language learning success in adults. Cereb Cortex 2023; 33:1217-1229. [PMID: 35348627 DOI: 10.1093/cercor/bhac131] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 03/05/2022] [Accepted: 03/07/2022] [Indexed: 11/14/2022] Open
Abstract
Investigating interhemispheric interactions between homologous cortical regions during language processing is of interest. Despite prevalent left hemisphere lateralization of language, the right hemisphere also plays an important role and interhemispheric connectivity is influenced by language experience and is implicated in second language (L2) acquisition. Regions involved in language processing have differential connectivity to other cortical regions and to each other, and play specific roles in language. We examined the interhemispheric interactions of subregions of the inferior frontal gyrus (areas 44 and 45), the adjacent area 9/46v in the middle frontal gyrus, the superior temporal gyrus (STG), and the posterior inferior parietal lobule (pIPL) in relation to distinct and specific aspects of L2 learning success. The results indicated that the connectivity between left and right areas 44 and 9/46v predicted improvement in sentence repetition, connectivity between left and right area 45 and mid-STG predicted improvement in auditory comprehension, and connectivity between left and right pIPL predicted improvement in reading speed. We show interhemispheric interactions in the specific context of facilitating performance in adult L2 acquisition that follow an anterior to posterior gradient in the brain, and are consistent with the respective roles of these regions in language processing.
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Affiliation(s)
- Kaija Sander
- Cognitive Neuroscience Unit, Montreal Neurological Institute, McGill University, Montréal, QC H3A 2B4, Canada.,Department of Neurology and Neurosurgery, McGill University, Montréal, QC H3A 2B4, Canada.,Centre for Research on Brain, Language, and Music (CRBLM), Montréal, QC H3G 2A8, Canada
| | - Xiaoqian Chai
- Department of Neurology and Neurosurgery, McGill University, Montréal, QC H3A 2B4, Canada.,Centre for Research on Brain, Language, and Music (CRBLM), Montréal, QC H3G 2A8, Canada.,McConnell Brain Imaging Centre, Montreal Neurological Institute, Montréal, QC H3A 2B4, Canada
| | - Elise B Barbeau
- Cognitive Neuroscience Unit, Montreal Neurological Institute, McGill University, Montréal, QC H3A 2B4, Canada.,Department of Neurology and Neurosurgery, McGill University, Montréal, QC H3A 2B4, Canada.,Centre for Research on Brain, Language, and Music (CRBLM), Montréal, QC H3G 2A8, Canada
| | - Shanna Kousaie
- Cognitive Neuroscience Unit, Montreal Neurological Institute, McGill University, Montréal, QC H3A 2B4, Canada.,Department of Neurology and Neurosurgery, McGill University, Montréal, QC H3A 2B4, Canada.,School of Psychology, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Michael Petrides
- Cognitive Neuroscience Unit, Montreal Neurological Institute, McGill University, Montréal, QC H3A 2B4, Canada.,Department of Neurology and Neurosurgery, McGill University, Montréal, QC H3A 2B4, Canada.,Centre for Research on Brain, Language, and Music (CRBLM), Montréal, QC H3G 2A8, Canada.,Department of Psychology, McGill University, Montréal, QC H3A 1G1, Canada
| | - Shari Baum
- Centre for Research on Brain, Language, and Music (CRBLM), Montréal, QC H3G 2A8, Canada.,School of Communication Sciences and Disorders, McGill University, Montréal, QC H3A 1G1, Canada
| | - Denise Klein
- Cognitive Neuroscience Unit, Montreal Neurological Institute, McGill University, Montréal, QC H3A 2B4, Canada.,Department of Neurology and Neurosurgery, McGill University, Montréal, QC H3A 2B4, Canada.,Centre for Research on Brain, Language, and Music (CRBLM), Montréal, QC H3G 2A8, Canada
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10
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Chang YN. The influence of oral vocabulary knowledge on individual differences in a computational model of reading. Sci Rep 2023; 13:1680. [PMID: 36717571 PMCID: PMC9886906 DOI: 10.1038/s41598-023-28559-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Accepted: 01/20/2023] [Indexed: 02/01/2023] Open
Abstract
Studies have demonstrated systematic individual differences in the degree of semantic reliance (SR) when reading aloud exception words in adult skilled readers. However, the origins of individual differences in reading remain unclear. Using a connectionist model of reading, this study investigated whether oral vocabulary knowledge may affect the degree of SR as a potential source of individual differences in reading. Variety in oral vocabulary knowledge was simulated by training the model to learn the mappings between spoken and meaning word forms with different vocabulary sizes and quantities of exposure to these vocabularies. The model's SR in the reading aloud task was computed. The result demonstrated that the model with varying amounts of oral exposure and vocabulary sizes had different levels of SR. Critically, SR was able to predict the performance of the model on reading aloud and nonword reading, which assimilated behavioural reading patterns. Further analysis revealed that SR was largely associated with the interaction between oral vocabulary exposure and oral vocabulary size. When the amount of exposure was limited, SR significantly increased with vocabulary sizes but decreased then with vocabulary sizes. Overall, the simulation results provide the first computational evidence of the direct link between oral vocabulary knowledge and the degree of SR as a source of individual differences in reading.
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Affiliation(s)
- Ya-Ning Chang
- Miin Wu School of Computing, National Cheng Kung University, Tainan, Taiwan. .,MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK.
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11
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With childhood hemispherectomy, one hemisphere can support—but is suboptimal for—word and face recognition. Proc Natl Acad Sci U S A 2022; 119:e2212936119. [PMID: 36282918 PMCID: PMC9636967 DOI: 10.1073/pnas.2212936119] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The right and left cerebral hemispheres are important for face and word recognition, respectively—a specialization that emerges over human development. The question is whether this bilateral distribution is necessary or whether a single hemisphere, be it left or right, can support both face and word recognition. Here, face and word recognition accuracy in patients (median age 16.7 y) with a single hemisphere following childhood hemispherectomy was compared against matched typical controls. In experiment 1, participants viewed stimuli in central vision. Across both face and word tasks, accuracy of both left and right hemispherectomy patients, while significantly lower than controls' accuracy, averaged above 80% and did not differ from each other. To compare patients' single hemisphere more directly to one hemisphere of controls, in experiment 2, participants viewed stimuli in one visual field to constrain initial processing chiefly to a single (contralateral) hemisphere. Whereas controls had higher word accuracy when words were presented to the right than to the left visual field, there was no field/hemispheric difference for faces. In contrast, left and right hemispherectomy patients, again, showed comparable performance to one another on both face and word recognition, albeit significantly lower than controls. Altogether, the findings indicate that a single developing hemisphere, either left or right, may be sufficiently plastic for comparable representation of faces and words. However, perhaps due to increased competition or “neural crowding,” constraining cortical representations to one hemisphere may collectively hamper face and word recognition, relative to that observed in typical development with two hemispheres.
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12
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Gore KR, Woollams AM, Bruehl S, Halai AD, Lambon Ralph MA. Direct Neural Evidence for the Contrastive Roles of the Complementary Learning Systems in Adult Acquisition of Native Vocabulary. Cereb Cortex 2022; 32:3392-3405. [PMID: 34875018 PMCID: PMC9376875 DOI: 10.1093/cercor/bhab422] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 10/27/2021] [Accepted: 10/28/2021] [Indexed: 01/01/2023] Open
Abstract
The Complementary Learning Systems (CLS) theory provides a powerful framework for considering the acquisition, consolidation, and generalization of new knowledge. We tested this proposed neural division of labor in adults through an investigation of the consolidation and long-term retention of newly learned native vocabulary with post-learning functional neuroimaging. Newly learned items were compared with two conditions: 1) previously known items to highlight the similarities and differences with established vocabulary and 2) unknown/untrained items to provide a control for non-specific perceptual and motor speech output. Consistent with the CLS, retrieval of newly learned items was supported by a combination of regions associated with episodic memory (including left hippocampus) and the language-semantic areas that support established vocabulary (left inferior frontal gyrus and left anterior temporal lobe). Furthermore, there was a shifting division of labor across these two networks in line with the items' consolidation status; faster naming was associated with more activation of language-semantic areas and lesser activation of episodic memory regions. Hippocampal activity during naming predicted more than half the variation in naming retention 6 months later.
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Affiliation(s)
- Katherine R Gore
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, University of Manchester, Manchester M13 9GB, UK
| | - Anna M Woollams
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, University of Manchester, Manchester M13 9GB, UK
| | - Stefanie Bruehl
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, University of Manchester, Manchester M13 9GB, UK
- St Mauritius Rehabilitation Centre, Meerbusch & Heinrich-Heine University, 40225 Duesseldorf, Germany
- Clinical and Cognitive Neurosciences, Department of Neurology, Medical Faculty, RWTH Aachen University, 52074 Aachen, Germany
| | - Ajay D Halai
- MRC Cognition & Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
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13
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Melillo R, Leisman G, Machado C, Machado-Ferrer Y, Chinchilla-Acosta M, Kamgang S, Melillo T, Carmeli E. Retained Primitive Reflexes and Potential for Intervention in Autistic Spectrum Disorders. Front Neurol 2022; 13:922322. [PMID: 35873782 PMCID: PMC9301367 DOI: 10.3389/fneur.2022.922322] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Accepted: 06/06/2022] [Indexed: 11/13/2022] Open
Abstract
We provide evidence to support the contention that many aspects of Autistic Spectrum Disorder (ASD) are related to interregional brain functional disconnectivity associated with maturational delays in the development of brain networks. We think a delay in brain maturation in some networks may result in an increase in cortical maturation and development in other networks, leading to a developmental asynchrony and an unevenness of functional skills and symptoms. The paper supports the close relationship between retained primitive reflexes and cognitive and motor function in general and in ASD in particular provided to indicate that the inhibition of RPRs can effect positive change in ASD.
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Affiliation(s)
- Robert Melillo
- Movement and Cognition Laboratory, Department of Physical Therapy, University of Haifa, Haifa, Israel
| | - Gerry Leisman
- Movement and Cognition Laboratory, Department of Physical Therapy, University of Haifa, Haifa, Israel
- Department of Neurology, University of the Medical Sciences of Havana, Havana, Cuba
| | - Calixto Machado
- Department of Clinical Neurophysiology, Institute for Neurology and Neurosurgery, Havana, Cuba
| | - Yanin Machado-Ferrer
- Department of Clinical Neurophysiology, Institute for Neurology and Neurosurgery, Havana, Cuba
| | | | - Shanine Kamgang
- Department of Neuroscience, Carleton University, Ottawa, ON, Canada
| | - Ty Melillo
- Northeast College of the Health Sciences, Seneca Falls, New York, NY, United States
| | - Eli Carmeli
- Movement and Cognition Laboratory, Department of Physical Therapy, University of Haifa, Haifa, Israel
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14
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Stefaniak JD, Geranmayeh F, Lambon Ralph MA. The multidimensional nature of aphasia recovery post-stroke. Brain 2022; 145:1354-1367. [PMID: 35265968 PMCID: PMC9128817 DOI: 10.1093/brain/awab377] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 08/20/2021] [Accepted: 09/18/2021] [Indexed: 12/28/2022] Open
Abstract
Language is not a single function, but instead results from interactions between neural representations and computations that can be damaged independently of each other. Although there is now clear evidence that the language profile in post-stroke aphasia reflects graded variations along multiple underlying dimensions ('components'), it is still entirely unknown if these distinct language components have different recovery trajectories and rely on the same, or different, neural regions during aphasia recovery. Accordingly, this study examined whether language components in the subacute stage: (i) mirror those observed in the chronic stage; (ii) recover together in a homogeneous manner; and (iii) have recovery trajectories that relate to changing activation in distinct or overlapping underlying brain regions. We analysed longitudinal data from 26 individuals with mild-moderate aphasia following left hemispheric infarct who underwent functional MRI and behavioural testing at ∼2 weeks and ∼4 months post-stroke. The language profiles in early post-stroke aphasia reflected three orthogonal principal components consisting of fluency, semantic/executive function and phonology. These components did not recover in a singular, homogeneous manner; rather, their longitudinal trajectories were uncorrelated, suggesting that aphasia recovery is heterogeneous and multidimensional. Mean regional brain activation during overt speech production in unlesioned areas was compared with patient scores on the three principal components of language at both the early and late time points. In addition, the change in brain activation over time was compared with the change on each of the principal component scores, both before and after controlling for baseline scores. We found that different language components were associated with changing activation in multiple, non-overlapping bilateral brain regions during aphasia recovery. Specifically, fluency recovery was associated with increasing activation in bilateral middle frontal gyri and right temporo-occipital middle temporal gyrus; semantic/executive recovery was associated with reducing activation in bilateral anterior temporal lobes; while phonology recovery was associated with reducing activation in bilateral precentral gyri, dorso-medial frontal poles and the precuneus. Overlapping clusters in the ventromedial prefrontal cortex were positively associated with fluency recovery but negatively associated with semantic/executive and phonology recovery. This combination of detailed behavioural and functional MRI data provides novel insights into the neural basis of aphasia recovery. Because different aspects of language seem to rely on different neural regions for recovery, treatment strategies that target the same neural region in all stroke survivors with aphasia might be entirely ineffective or even impair recovery, depending on the specific language profile of each individual patient.
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Affiliation(s)
- James D Stefaniak
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
- Department of Psychiatry, University of Cambridge, Cambridge CB2 0SZ, UK
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9GB, UK
| | - Fatemeh Geranmayeh
- Computational Cognitive and Clinical Neuroimaging Laboratory, Department of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, London W12 0NN, UK
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15
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Neurodidactics of Languages: Neuromyths in Multilingual Learners. MATHEMATICS 2022. [DOI: 10.3390/math10020196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
From the perspective of neuroscience applied to education and the teaching of foreign languages, this exploratory study analyzes the beliefs and conceptions about the functioning of the brain and language learning in students enrolled in Education degrees at the Melilla campus of the University of Granada. The sample consisted of 397 participants. The data collection was carried out by means of a questionnaire designed for this purpose, consisting of questions related to the context and linguistic background of the respondents and to educational neuromyths regarding language learning. The data were analyzed using the SPSS version 27 statistical software, and univariate and bivariate analyses were carried out according to the three grouping dimensions: (a) brain functioning, (b) multiple intelligences and learning styles, and (c) language learning. The results indicate the prevalence of neuromyths related to general concepts, which determine the learning comprehension. This corroborates the findings of research studies in other contexts. Although the participants do not show a prevalence of neuromyths regarding foreign language learning, presumably due to their experiences in multilingual contexts, which constitutes the main contribution of this study.
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16
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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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17
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Biological constraints on neural network models of cognitive function. Nat Rev Neurosci 2021; 22:488-502. [PMID: 34183826 PMCID: PMC7612527 DOI: 10.1038/s41583-021-00473-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/17/2021] [Indexed: 02/06/2023]
Abstract
Neural network models are potential tools for improving our understanding of complex brain functions. To address this goal, these models need to be neurobiologically realistic. However, although neural networks have advanced dramatically in recent years and even achieve human-like performance on complex perceptual and cognitive tasks, their similarity to aspects of brain anatomy and physiology is imperfect. Here, we discuss different types of neural models, including localist, auto-associative, hetero-associative, deep and whole-brain networks, and identify aspects under which their biological plausibility can be improved. These aspects range from the choice of model neurons and of mechanisms of synaptic plasticity and learning to implementation of inhibition and control, along with neuroanatomical properties including areal structure and local and long-range connectivity. We highlight recent advances in developing biologically grounded cognitive theories and in mechanistically explaining, on the basis of these brain-constrained neural models, hitherto unaddressed issues regarding the nature, localization and ontogenetic and phylogenetic development of higher brain functions. In closing, we point to possible future clinical applications of brain-constrained modelling.
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18
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Castro N. Methodological Considerations for Incorporating Clinical Data Into a Network Model of Retrieval Failures. Top Cogn Sci 2021; 14:111-126. [PMID: 33818913 DOI: 10.1111/tops.12531] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 03/17/2021] [Accepted: 03/17/2021] [Indexed: 12/01/2022]
Abstract
Difficulty retrieving information (e.g., words) from memory is prevalent in neurogenic communication disorders (e.g., aphasia and dementia). Theoretical modeling of retrieval failures often relies on clinical data, despite methodological limitations (e.g., locus of retrieval failure, heterogeneity of individuals, and progression of disorder/disease). Techniques from network science are naturally capable of handling these limitations. This paper reviews recent work using a multiplex lexical network to account for word retrieval failures and highlights how network science can address the limitations of clinical data. Critically, any model we employ could impact clinical practice and patient lives, harkening the need for theoretically well-informed network models.
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Affiliation(s)
- Nichol Castro
- Department of Communicative Disorders and Sciences, University at Buffalo
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19
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Sajid N, Holmes E, Hope TM, Fountas Z, Price CJ, Friston KJ. Simulating lesion-dependent functional recovery mechanisms. Sci Rep 2021; 11:7475. [PMID: 33811259 PMCID: PMC8018968 DOI: 10.1038/s41598-021-87005-4] [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: 06/30/2020] [Accepted: 03/22/2021] [Indexed: 01/13/2023] Open
Abstract
Functional recovery after brain damage varies widely and depends on many factors, including lesion site and extent. When a neuronal system is damaged, recovery may occur by engaging residual (e.g., perilesional) components. When damage is extensive, recovery depends on the availability of other intact neural structures that can reproduce the same functional output (i.e., degeneracy). A system's response to damage may occur rapidly, require learning or both. Here, we simulate functional recovery from four different types of lesions, using a generative model of word repetition that comprised a default premorbid system and a less used alternative system. The synthetic lesions (i) completely disengaged the premorbid system, leaving the alternative system intact, (ii) partially damaged both premorbid and alternative systems, and (iii) limited the experience-dependent plasticity of both. The results, across 1000 trials, demonstrate that (i) a complete disconnection of the premorbid system naturally invoked the engagement of the other, (ii) incomplete damage to both systems had a much more devastating long-term effect on model performance and (iii) the effect of reducing learning capacity within each system. These findings contribute to formal frameworks for interpreting the effect of different types of lesions.
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Affiliation(s)
- Noor Sajid
- Wellcome Centre for Human Neuroimaging, University College London, UCL Queen Square Institute of Neurology, 12 Queen Square, London, WC1N 3AR, UK.
| | - Emma Holmes
- Wellcome Centre for Human Neuroimaging, University College London, UCL Queen Square Institute of Neurology, 12 Queen Square, London, WC1N 3AR, UK
| | - Thomas M Hope
- Wellcome Centre for Human Neuroimaging, University College London, UCL Queen Square Institute of Neurology, 12 Queen Square, London, WC1N 3AR, UK
| | - Zafeirios Fountas
- Wellcome Centre for Human Neuroimaging, University College London, UCL Queen Square Institute of Neurology, 12 Queen Square, London, WC1N 3AR, UK
- Huawei 2012 Laboratories, London, UK
| | - Cathy J Price
- Wellcome Centre for Human Neuroimaging, University College London, UCL Queen Square Institute of Neurology, 12 Queen Square, London, WC1N 3AR, UK
| | - Karl J Friston
- Wellcome Centre for Human Neuroimaging, University College London, UCL Queen Square Institute of Neurology, 12 Queen Square, London, WC1N 3AR, UK
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20
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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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21
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Lambon Ralph MA. Listen up: it is time to integrate neuroscience and technologies into aphasia rehabilitation. J Neurol Neurosurg Psychiatry 2021; 92:jnnp-2020-325349. [PMID: 33563799 DOI: 10.1136/jnnp-2020-325349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 01/07/2021] [Indexed: 11/03/2022]
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