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BACKGROUND: Discourse analysis has recently received much attention in the aphasia literature. Even if post-stroke language recovery occurs throughout the longitudinal continuum of recovery, very few studies have documented discourse changes from the hyperacute to the chronic phases of recovery. AIMS: To document a multilevel analysis of discourse changes from the hyperacute phase to the chronic phase of post-stroke recovery using a series of single cases study designs. METHODS & PROCEDURES: Four people with mild to moderate post-stroke aphasia underwent four assessments (hyperacute: 0-24 h; acute: 24-72 h; subacute: 7-14 days; and chronic: 6-12 months post-onset). Three discourse tasks were performed at each time point: a picture description, a personal narrative and a story retelling. Multilevel changes in terms of macro- and microstructural aspects were analysed. The results of each discourse task were combined for each time point. Individual effect sizes were computed to evaluate the relative strength of changes in an early and a late recovery time frame. OUTCOMES & RESULTS: Macrostructural results revealed improvements throughout the recovery continuum in terms of coherence and thematic efficiency. Also, the microstructural results demonstrated linguistic output improvement for three out of four participants. Namely, lexical diversity and the number of correct information units/min showed a greater gain in the early compared with the late recovery phase. CONCLUSIONS & IMPLICATIONS: This study highlights the importance of investigating all discourse processing levels as the longitudinal changes in discourse operate differently at each phase of recovery. Overall results support future longitudinal discourse investigation in people with post-stroke aphasia. WHAT THIS PAPER ADDS: What is already known on the subject Multi-level discourse analysis allows for in-depth analysis of underlying discourse processes. To date, very little is known on the longitudinal discourse changes from aphasia onset through to the chronic stage of recovery. This study documents multi-level discourse features in four people with mild to moderate aphasia in the hyperacute, acute, subacute and chronic stage of post-stroke aphasia recovery. What this paper adds to existing knowledge The study found that most discourse variables demonstrated improvement throughout time. Macrostructural variables of coherence and thematic units improved throughout the continuum whereas microstructural variables demonstrated greater gains in the early compared to the late period of recovery. What are the potential or actual clinical implications of this work? This study suggests that multilevel discourse analysis will allow a better understanding of post-stroke aphasia recovery, although more research is needed to determine the clinical utility of these findings. Future research may wish to investigate longitudinal discourse recovery in a larger sample of people with aphasia with heterogenous aphasia profiles and severities.
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Afasia , Accidente Cerebrovascular , Humanos , Afasia/etiología , Afasia/rehabilitación , Atención , Lenguaje , Lingüística , Accidente Cerebrovascular/complicaciones , Estudios Longitudinales , Análisis Multinivel , Recuperación de la FunciónRESUMEN
Research on language processing requires language-specific norms of pictorial and linguistic experimental stimuli across different psycholinguistic variables. Such normative data have not yet been collected for Lebanese Arabic (LA), an Arabic dialect. Arabic languages are characterized by diglossia: while modern standard Arabic is their common means of formal communication, Arabic dialects are the medium of oral communication within each community. This claims for specific dialectal norms. Thus, the main goal of the present study was to collect normative LA data for 380 pictures taken from Cykowicz, Friedman, Rothstein, and Snodgrass (The Quarterly Journal of Experimental Psychology Section A 50(3):560-585; including the 260 pictures of Snodgrass & Vanderwart in Journal of experimental psychology: Human learning and memory 6(2):174-215, 1980) using a sample of 248 native LA speakers. Norms are reported for name agreement, conceptual familiarity, imageability and subjective frequency, together with word length in number of letters and syllables. We compared the obtained norms with the normative data of other Arabic dialects (Levantine, Tunisian and Gulf Arabic) and with English, French and Spanish. Results showed the distinction of LA from the other Arabic dialects. This provides support of specific dialectal Arabic norms and will allow researchers to rigorously select the stimuli to investigate language processing in LA-speaking populations.
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Lenguaje , Nombres , Humanos , Psicolingüística , Reconocimiento en Psicología , Percepción VisualRESUMEN
Intrinsic connectivity networks (ICNs) identified through task-free fMRI (tf-fMRI) offer the opportunity to investigate human brain circuits involved in language processes without requiring participants to perform challenging cognitive tasks. In this study, we assessed the ability of tf-fMRI to isolate reproducible networks critical for specific language functions and often damaged in primary progressive aphasia (PPA). First, we performed whole-brain seed-based correlation analyses on tf-fMRI data to identify ICNs anchored in regions known for articulatory, phonological, and semantic processes in healthy male and female controls (HCs). We then evaluated the reproducibility of these ICNs in an independent cohort of HCs, and recapitulated their functional relevance with a post hoc meta-analysis on task-based fMRI. Last, we investigated whether atrophy in these ICNs could inform the differential diagnosis of nonfluent/agrammatic, semantic, and logopenic PPA variants. The identified ICNs included a dorsal articulatory-phonological network involving inferior frontal and supramarginal regions; a ventral semantic network involving anterior middle temporal and angular gyri; a speech perception network involving superior temporal and sensorimotor regions; and a network between posterior inferior temporal and intraparietal regions likely linking visual, phonological, and attentional processes for written language. These ICNs were highly reproducible across independent groups and revealed areas consistent with those emerging from task-based meta-analysis. By comparing ICNs' spatial distribution in HCs with patients' atrophy patterns, we identified ICNs associated with each PPA variant. Our findings demonstrate the potential use of tf-fMRI to investigate the functional status of language networks in patients for whom activation studies can be methodologically challenging.SIGNIFICANCE STATEMENT We showed that a single, short, task-free fMRI acquisition is able to identify four reproducible and relatively segregated intrinsic left-dominant networks associated with articulatory, phonological, semantic, and multimodal orthography-to-phonology processes, in HCs. We also showed that these intrinsic networks relate to syndrome-specific atrophy patterns in primary progressive aphasia. Collectively, our results support the application of task-free fMRI in future research to study functionality of language circuits in patients for whom tasked-based activation studies might be methodologically challenging.
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Afasia Progresiva Primaria/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Lenguaje , Red Nerviosa/diagnóstico por imagen , Neuroimagen/métodos , Anciano , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana EdadRESUMEN
Older adults display impairments in accessing episodic, but not semantic details, when specifically requested to construct autobiographical events. How aging affects access to autobiographical information under conditions of low retrieval constraint remains unclear. We examined the production of episodic and "non-episodic" details in young (n = 25) and older (n = 24) adults on a novel autobiographical narrative task free from constraints on the type of information to be retrieved (Thoughts task), compared with the standard autobiographical memory and picture description tasks. Older adults generated fewer episodic and more non-episodic details on the memory task than young adults, however there was no age difference in detail profiles on the Thoughts task. Under these conditions of low retrieval constraint, narratives of young and older adults consisted of mostly personal and general semantic content. Young adults also provided less episodic and more semantic details on the Thoughts than the memory task, while older adults provided similar amounts of details across tasks. These results reveal that both young and older adults retrieve semantic autobiographical content under minimally constrained retrieval conditions. Moreover, aging may impact upon the ability to shift the detail types (episodic, semantic) provided in response to changing demands of different autobiographical narrative tasks.
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Memoria Episódica , Semántica , Anciano , Envejecimiento/fisiología , Humanos , Recuerdo Mental/fisiología , Narración , Adulto JovenRESUMEN
The goal of the study was to determine whether the semantic variant of primary progressive aphasia (svPPA) affects the intrinsic connectivity network anchored to left and right anterior hippocampus, but spares the posterior hippocampus. A resting-state functional connectivity MRI (rs-fcMRI) study was conducted in a group of patients with svPPA and in controls, using a seed-to-voxel approach. In comparison to controls, massively reduced connectivity was found in the anterior hippocampus, mainly the left one, for svPPA patients but not in the left or right posterior hippocampus. In svPPA, the anterior hippocampus showed reduced functional connectivity with regions implicated in the semantic memory network. Significant correlation was also found between the functional connectivity strength of the left anterior hippocampus and the ventromedial cortex, and performance in semantic tasks. These findings indicate that the functional disconnection of the anterior hippocampus may be a promising in vivo biomarker of svPPA and illustrate the role of this hippocampal subregion in the semantic memory system.
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Afasia Progresiva Primaria/diagnóstico por imagen , Hipocampo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Descanso , Anciano , Afasia Progresiva Primaria/fisiopatología , Afasia Progresiva Primaria/psicología , Femenino , Hipocampo/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Descanso/fisiologíaRESUMEN
Despite a well-documented pattern of semantic impairment, the patterns of brain activation during semantic processing in semantic variant primary progressive aphasia (svPPA) still remain poorly understood. In the current study, one svPPA patient (EC) and six elderly controls carried out a general-level semantic categorization task while their brain activity was recorded using magnetoencephalography (MEG). Despite similar behavioral performance, EC showed hyperactivation of the left inferior temporal gyrus (ITG) and right anterior temporal lobe (ATL) relative to controls. This suggests that periatrophic regions within the ATL region may support preserved semantic abilities in svPPA.
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Afasia Progresiva Primaria/fisiopatología , Encéfalo/fisiopatología , Anciano , Femenino , Humanos , Magnetoencefalografía , Masculino , Pruebas Neuropsicológicas , Lóbulo Temporal/fisiopatologíaRESUMEN
Idiopathic rapid eye movement sleep behavior disorder (iRBD) is a major risk factor for Parkinson's disease and dementia with Lewy bodies. Anatomical gray matter abnormalities in the motor cortico-subcortical loop areas remain under studied in iRBD patients. We acquired T1-weighted images and administrated quantitative motor tasks in 41 patients with polysomnography-confirmed iRBD and 41 healthy subjects. Cortical thickness and voxel-based morphometry (VBM) analyses were performed to investigate local cortical thickness and gray matter volume changes, vertex-based shape analysis to investigate shape of subcortical structures, and structure-based volumetric analyses to investigate volumes of subcortical and brainstem structures. Cortical thickness analysis revealed thinning in iRBD patients in bilateral medial superior frontal, orbitofrontal, anterior cingulate cortices, and the right dorsolateral primary motor cortex. VBM results showed lower gray matter volume in iRBD patients in the frontal lobes, anterior cingulate gyri, and caudate nucleus. Shape analysis revealed extensive surface contraction in the external and internal segments of the left pallidum. Clinical and motor impaired features in iRBD were associated with anomalies of the motor cortico-subcortical loop. In summary, iRBD patients showed numerous gray matter structural abnormalities in the motor cortico-subcortical loop, which are associated with lower motor performance and clinical manifestations of iRBD.
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Sustancia Gris/diagnóstico por imagen , Actividad Motora/fisiología , Corteza Motora/diagnóstico por imagen , Corteza Motora/fisiología , Destreza Motora/fisiología , Trastorno de la Conducta del Sueño REM/diagnóstico por imagen , Anciano , Femenino , Sustancia Gris/fisiología , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiología , Tamaño de los Órganos/fisiología , Trastorno de la Conducta del Sueño REM/fisiopatologíaRESUMEN
Perceptual experience plays a critical role in the conceptual representation of words. Higher levels of semantic variables such as imageability, concreteness, and sensory experience are generally associated with faster and more accurate word processing. Nevertheless, these variables tend to be assessed mostly on the basis of visual experience. This underestimates the potential contributions of other perceptual modalities. Accordingly, recent evidence has stressed the importance of providing modality-specific perceptual strength norms. In the present study, we developed French Canadian norms of visual and auditory perceptual strength (i.e., the modalities that have major impact on word processing) for 3,596 nouns. We then explored the relationship between these newly developed variables and other lexical, orthographic, and semantic variables. Finally, we demonstrated the contributions of visual and auditory perceptual strength ratings to visual word processing beyond those of other semantic variables related to perceptual experience (e.g., concreteness, imageability, and sensory experience ratings). The ratings developed in this study are a meaningful contribution toward the implementation of new studies that will shed further light on the interaction between linguistic, semantic, and perceptual systems.
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Psicolingüística , Adolescente , Insuficiencia Suprarrenal , Adulto , Canadá , Cognición , Femenino , Retardo del Crecimiento Fetal , Humanos , Masculino , Osteocondrodisplasias , Semántica , Anomalías Urogenitales , Adulto JovenRESUMEN
In the last decade, research has shown that word processing is influenced by the lexical and semantic features of words. However, norms for a crucial semantic variable-that is, conceptual familiarity-have not been available for a sizeable French database. We thus developed French Canadian conceptual familiarity norms for 3,596 nouns. This enriches Desrochers and Thompson's (2009) database, in which subjective frequency and imageability values are already available for the same words. We collected online data from 313 Canadian French speakers. The full database of conceptual familiarity ratings is freely available at http://lingualab.ca/fr/projets/normes-de-familiarite-conceptuelle . We then demonstrated the utility of these new conceptual familiarity norms by assessing their contribution to lexical decision times. We conducted a stepwise regression model with conceptual familiarity in the last step. This allowed us to assess the independent contribution of conceptual familiarity beyond the contributions of other well-known psycholinguistic variables, such as frequency, imageability, and age of acquisition. The results showed that conceptual familiarity facilitated lexical decision latencies. In sum, these ratings will help researchers select French stimuli for experiments in which conceptual familiarity must be taken into account.
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Reconocimiento en Psicología , Adolescente , Adulto , Canadá , Bases de Datos Factuales , Toma de Decisiones , Femenino , Humanos , Masculino , Psicolingüística , Semántica , Adulto JovenRESUMEN
Primary progressive aphasia (PPA) is a heterogeneous neurodegenerative condition in which the most prominent clinical feature is language difficulties. Other cognitive domains have been described to remain unaffected at the early stages of the disease and, therefore, excluded from diagnostic criteria. However, we show in this article that executive function (EF) disorders may be present in the 3 variants (nonfluent/agrammatic, logopenic, and semantic) of PPA. We also illustrate changes in language and EF by means of a 3-year behavioral and neuroimaging longitudinal study of a patient suffering from the semantic variant of PPA. This review provides an update on current knowledge of PPA, suggesting that dysexecutive symptoms may be encountered in the 3 PPA variants, in their early phases and/or in more advanced stages, when atrophy extends to adjacent brain areas.
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Afasia Progresiva Primaria/diagnóstico , Afasia Progresiva Primaria/psicología , Encéfalo/patología , Función Ejecutiva , Lenguaje , Afasia Progresiva Primaria/patología , Afasia Progresiva Primaria/fisiopatología , Atrofia/patología , Encéfalo/fisiopatología , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Neuroimagen , SemánticaRESUMEN
Clinical symptoms observed in Alzheimer's disease (AD) patients may reflect variations within specific large-scale brain networks, modeling AD as a disconnection syndrome. The present magnetic resonance imaging study aims to compare the organization of gray matter structural covariance networks between 109 cognitively unimpaired controls (CTRL) and 109 AD patients positive to beta-amyloid at the early stages of the disease, using voxel-based morphometry. The default-mode network (DMN; medial temporal lobe subsystem) was less extended in AD patients in comparison with CTRL, with a significant decrease in the structural association between the entorhinal cortex and the medial prefrontal and the dorsolateral prefrontal cortices. The DMN (midline core subsystem) was also less extended in AD patients. Trends toward increased structural association were observed in the salience and executive control networks. The observed changes suggest that early disruptions in structural association between heteromodal association cortices and the entorhinal cortex could contribute to an isolation of the hippocampal formation, potentially giving rise to the clinical hallmark of AD, progressive memory impairment. It also provides critical support to the hypothesis that the reduced connectivity within the DMN in early AD is accompanied by an enhancement of connectivity in the salience and executive control networks.
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Enfermedad de Alzheimer/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Sustancia Gris/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/líquido cefalorraquídeo , Péptidos beta-Amiloides/líquido cefalorraquídeo , Biomarcadores/líquido cefalorraquídeo , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Escala del Estado Mental , Persona de Mediana Edad , Vías Nerviosas/diagnóstico por imagen , Fragmentos de Péptidos/líquido cefalorraquídeoRESUMEN
Idiopathic rapid eye movement sleep behavior disorder is a parasomnia that is a risk factor for dementia with Lewy bodies and Parkinson's disease. Brain function impairments have been identified in this disorder, mainly in the frontal and posterior cortical regions. However, the anatomical support for these dysfunctions remains poorly understood. We investigated gray matter thickness, gray matter volume, and white matter integrity in patients with idiopathic rapid eye movement sleep behavior disorder. Twenty-four patients with polysomnography-confirmed idiopathic rapid eye movement sleep behavior disorder and 42 healthy individuals underwent a 3-tesla structural and diffusion magnetic resonance imaging examination using corticometry, voxel-based morphometry, and diffusion tensor imaging. In the patients with idiopathic rapid eye movement sleep behavior disorder, decreased cortical thickness was observed in the frontal cortex, the lingual gyrus, and the fusiform gyrus. Gray matter volume was reduced in the superior frontal sulcus only. Patients showed no increased gray matter thickness or volume. Diffusion tensor imaging analyses revealed no significant white matter differences between groups. Using corticometry in patients with idiopathic rapid eye movement sleep behavior disorder, several new cortical regions with gray matter alterations were identified, similar to those reported in dementia with Lewy bodies and Parkinson's disease. These findings provide some anatomical support for previously identified brain function impairments in this disorder.
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Corteza Cerebral/patología , Trastorno de la Conducta del Sueño REM/patología , Anciano , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , PolisomnografíaRESUMEN
We aimed to characterize difficulties in famous face naming in three poststroke aphasic patients with a lesion limited to the left mid-posterior temporal language regions, sparing the anterior temporal lobe. The patients did not present semantic deficits specific to known people. Nonetheless, they showed difficulties naming famous buildings in addition to famous faces, but they were comparable to healthy controls in generating proper names. Our results support the critical role of the mid-posterior temporal language regions in the lexical retrieval of proper names, namely from pictorial stimuli, in absence of semantic impairments.
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Anomia/patología , Afasia/patología , Recuerdo Mental/fisiología , Accidente Cerebrovascular/complicaciones , Lóbulo Temporal/patología , Anciano , Anomia/complicaciones , Afasia/complicaciones , Personajes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nombres , SemánticaRESUMEN
Semantic deficits in Alzheimer's disease (AD) are often more severe for items that are characterized by a unique semantic and lexical association, such as famous people. Whether these deficits are due to the degradation of semantic information or a deficit in the ability to intentionally access semantic knowledge remains controversial. To assess the integrity of the semantic system without explicitly accessing it, a priming paradigm was used. Semantic and repetition priming effects in individuals with AD (n = 7) and age-matched controls (n = 13) were measured in a familiarity judgment task using visually-presented names of famous people. A defective priming effect in AD subjects was observed in the semantic priming but not in the repetition priming condition. Therefore, the semantic impairments observed in AD may indicate a degraded representation of the semantic information concerning famous people.
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Enfermedad de Alzheimer/psicología , Memoria Implícita , Semántica , Anciano , Anciano de 80 o más Años , Personajes , Femenino , Humanos , MasculinoRESUMEN
Background: Executive functions (EF) are central to instrumental activities of daily living (IADL). A novel approach to the assessment of the impact of EF difficulties on IADL may be through the speech acts produced when performing IADL-inspired tasks in a laboratory-apartment. Speech acts may act as a window to the difficulties encountered during task performance. Objective: We aim to 1) qualitatively describe the speech acts produced by participants with mild neurocognitive disorder (mild NCD) and healthy controls (HC) as they performed 4 IADL-inspired tasks in a laboratory-apartment, and to then 2) compare their use in both groups. Methods: The participants' performance was videotaped, and speech acts produced were transcribed. Qualitative description of all speech acts was performed, followed by a deductive-inductive pattern coding of data. Statistical analyses were performed to further compare their use by mild NCD participants and HC. Results: Twenty-two participants took part in the study (n mild NCDâ=â11; n HCâ=â11). Meta-categories of data emerged from pattern coding: strategies, barriers, reactions, and consequences. Mild NCD participants used significantly more strategies and barriers than did HC. They were more defensive of their performance, and more reactive to their difficulties than HC. Mild NCD participants' verification of having completed all tasks was less efficient than controls. Conclusions: An assessment of speech acts produced during the performance of IADL-inspired tasks in a laboratory-apartment may allow to detect changes in the use of language which may reflect EF difficulties linked to cognitive decline.
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Disfunción Cognitiva , Envejecimiento Saludable , Humanos , Actividades Cotidianas/psicología , Habla , Disfunción Cognitiva/psicología , Función Ejecutiva , Pruebas NeuropsicológicasRESUMEN
Objective: Limited normative data (including psychometric properties) are currently available on discourse tasks in non-dominant languages such as Laurentian (Quebec) French. The lack of linguistic and cultural adaptation has been identified as a barrier to discourse assessment. The main aim of this study is to document inter-rater and test-retest reliability properties of the picnic scene of the Western Aphasia Battery - Revised (WAB-R), including the cultural adaptation of an information content unit (ICU) list, and provide a normative reference for persons without brain injury (PWBI). Method: To do so, we also aimed to adapt an ICU checklist culturally and linguistically for Laurentian French speakers. Discourse samples were collected from 66 PWBI using the picture description task of the WAB-R. The ICU list was first adapted into Laurentian French. Then, ICUs and thematic units (TUs) were extracted manually, and microstructural variables were extracted using CLAN. Inter-rater reliability and test-retest reliability were determined. Results: Excellent inter-rater reliability was obtained for ICUs and TUs, as well as for all microstructural variables, except for mean length of utterance, which was found to be good. Conversely, test-retest reliability ranged from poor to moderate for all variables. Conclusion: The present study provides a validated ICU checklist for clinicians and researchers working with Laurentian French speakers when assessing discourse with the picnic scene of the WAB-R. It also addresses the gap in available psychometric data regarding inter-rater and test-retest reliability in PWBI.
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We systematically reviewed the literature on neural changes following anomia treatment post-stroke. We conducted electronic searches of CINAHL, Cochrane Trials, Embase, Ovid MEDLINE, MEDLINE-in-Process and PsycINFO databases; two independent raters assessed all abstracts and full texts. Accepted studies reported original data on adults with post-stroke aphasia, who received behavioural treatment for anomia, and magnetic resonance brain imaging (MRI) pre- and post-treatment. Search results yielded 2481 citations; 33 studies were accepted. Most studies employed functional MRI and the quality of reporting neuroimaging methodology was variable, particularly for pre-processing steps and statistical analyses. The most methodologically robust data were synthesized, focusing on pre- versus post-treatment contrasts. Studies more commonly reported increases (versus decreases) in activation following naming therapy, primarily in the left supramarginal gyrus, and left/bilateral precunei. Our findings highlight the methodological heterogeneity across MRI studies, and the paucity of robust evidence demonstrating direct links between brain and behaviour in anomia rehabilitation.
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Afasia , Accidente Cerebrovascular , Adulto , Humanos , Anomia/diagnóstico por imagen , Anomia/etiología , Anomia/terapia , Afasia/diagnóstico por imagen , Afasia/etiología , Afasia/terapia , Neuroimagen , Plasticidad Neuronal , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/terapiaRESUMEN
PURPOSE: Main concept (MC) analysis is a well-documented method of discourse analysis in adults with and without brain injury. This study aims to develop a MC checklist that is culturally and linguistically adapted for Canadian French speakers and examine its reliability. We also documented microstructural properties and provide a normative reference in persons not brain injured (PNBIs). METHOD: Discourse samples from 43 PNBIs were collected. All participants completed the Cinderella story retell task twice. Manual transcription was performed for all samples. The 34 MCs for the Cinderella story retell task were adapted into Canadian French and used to score all transcripts. In addition, microstructural variables were extracted using Computerized Language Analysis (CLAN). Intraclass correlation coefficients were computed to assess interrater reliability for MC codes and microstructural variables. Test-retest reliability was assessed using intraclass correlations, Spearman's rho correlations, and the Wilcoxon signed-ranks test. Bland-Altman plots were used to examine the agreement of the discourse measures between the two sessions. RESULTS: The MC checklist for the Cinderella story retell task adapted for Canadian French speakers is provided. Good-to-excellent interrater reliability was obtained for most MC codes; however, reliability ranged from poor to excellent for the "inaccurate and incomplete" code. Microstructural variables demonstrated excellent interrater reliability. Test-retest reliability ranged from poor to excellent for all variables, with the majority falling between moderate and excellent. Bland-Altman plots illustrated the limits of agreement between test and retest. CONCLUSIONS: This study provides the MC checklist for clinicians and researchers working with Canadian French speakers when assessing discourse with the Cinderella story retell task. It also addresses the gap in available psychometric data regarding test-retest reliability in PNBIs. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.24171087.
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Lesiones Encefálicas , Lenguaje , Adulto , Humanos , Reproducibilidad de los Resultados , Canadá , PsicometríaRESUMEN
White matter is often severely affected after human ischaemic stroke. While animal studies have suggested that various factors may contribute to white matter structural damage after ischaemic stroke, the characterization of damaging processes to the affected hemisphere after human stroke remains poorly understood. Thus, the present study aims to thoroughly describe the longitudinal pattern of evolution of diffusion magnetic resonance imaging metrics in different parts of the ipsilesional white matter after stroke. We acquired diffusion and anatomical images in 17 patients who had suffered from a single left hemisphere ischaemic stroke, at 24-72â h, 8-14 days and 6 months post-stroke. For each patient, we created three regions of interest: (i) the white matter lesion; (ii) the perilesional white matter; and (iii) the remaining white matter of the left hemisphere. We extracted diffusion metrics (fractional anisotropy, mean, axial and radial diffusivities) for each region and conducted two-way repeated measures ANOVAs with stage post-stroke (acute, subacute and chronic) × regions of interest (white matter lesion, perilesional white matter and remaining white matter). Fractional anisotropy values stayed consistent across time-points, with significantly lower values in the white matter lesion compared to the perilesional white matter and remaining white matter tissue. Fractional anisotropy values of the perilesional white matter were also significantly lower than that of the remaining white matter. Mean, axial and radial diffusivities in the white matter lesion were all decreased in the acute stage compared to perilesional white matter and remaining white matter, but significantly increased in both the subacute and chronic stages. Significant increases in mean and radial diffusivities in the perilesional white matter were seen in the later stages of stroke. Our findings suggest that various physiological processes are at play in the acute, subacute and chronic stages following ischaemic stroke, with the infarct territory and perilesional white matter affected by ischaemia at different rates and to different extents throughout the stroke recovery stages. The examination of multiple diffusivity metrics may inform us about the mechanisms occurring at different time-points, i.e. focal swelling, axonal damage or myelin loss.
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Semantic variant primary progressive aphasia is a clinical syndrome characterized by marked semantic deficits, anterior temporal lobe atrophy and reduced connectivity within a distributed set of regions belonging to the functional network associated with semantic processing. However, to fully depict the clinical signature of semantic variant primary progressive aphasia, it is necessary to also characterize preserved neural networks and linguistic abilities, such as those subserving speech production. In this case-control observational study, we employed whole-brain seed-based connectivity on task-free MRI data of 32 semantic variant primary progressive aphasia patients and 46 healthy controls to investigate the functional connectivity of the speech production network and its relationship with the underlying grey matter. We investigated brain-behaviour correlations with speech fluency measures collected through clinical tests (verbal agility) and connected speech (speech rate and articulation rate). As a control network, we also investigated functional connectivity within the affected semantic network. Patients presented with increased connectivity in the speech production network between left inferior frontal and supramarginal regions, independent of underlying grey matter volume. In semantic variant primary progressive aphasia patients, preserved (verbal agility) and increased (articulation rate) speech fluency measures correlated with increased connectivity between inferior frontal and supramarginal regions. As expected, patients demonstrated decreased functional connectivity in the semantic network (dependent on the underlying grey matter atrophy) associated with average nouns' age of acquisition during connected speech. Collectively, these results provide a compelling model for studying compensation mechanisms in response to disease that might inform the design of future rehabilitation strategies in semantic variant primary progressive aphasia.