The longitudinal trajectory of discourse from the hyperacute to the chronic phase in mild to moderate poststroke aphasia recovery: A case series study.

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.

A Standardized Set of 380 Pictures for Lebanese Arabic: Norms for Name Agreement, Conceptual Familiarity, Imageability, and Subjective Frequency.

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.

A MEG study of the neural substrates of semantic processing in semantic variant primary progressive aphasia.

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.

Visual and auditory perceptual strength norms for 3,596 French nouns and their relationship with other psycholinguistic variables.

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.

Norms of conceptual familiarity for 3,596 French nouns and their contribution in lexical decision.

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.

Altered Gray Matter Structural Covariance Networks in Early Stages of Alzheimer's Disease.

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.

Proper name anomia in poststroke aphasics: evidence from a multiple-case study.

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.

Speech Acts as a Window to the Difficulties in Instrumental Activities of Daily Living: A Qualitative Descriptive Study in Mild Neurocognitive Disorder and Healthy Aging.

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 NCD = 11; n HC = 11). 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.

Reliability of the picture description task of the Western Aphasia Battery - revised in Laurentian French persons without brain injury.

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.

Treatment-induced neuroplasticity after anomia therapy in post-stroke aphasia: A systematic review of neuroimaging studies.

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.

Adaptation and Reliability of the Cinderella Story Retell Task in Canadian French Persons Without Brain Injury.

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.

The role of the left anterior temporal lobe in exception word reading: reconciling patient and neuroimaging findings.

Semantic dementia (SD) is a neurodegenerative disease that occurs following the atrophy of the anterior temporal lobes (ATLs). It is characterised by the degradation of semantic knowledge and difficulties in reading exception words (surface dyslexia). This disease has highlighted the role of the ATLs in the process of exception word reading. However, imaging studies in healthy subjects have failed to detect activation of the ATLs during exception word reading. The aim of the present study was to test whether the functional brain regions that mediate exception word reading in normal readers overlap those brain regions atrophied in SD. In Study One, we map the brain regions of grey matter atrophy in AF, a patient with mild SD and surface dyslexia profile. In Study Two, we map the activation pattern associated with exception word compared to pseudoword reading in young, healthy participants using fMRI. The results revealed areas of significant activation in healthy subjects engaged in the exception word reading task in the left anterior middle temporal gyrus, in a region observed to be atrophic in the patient AF. These results reconcile neuropsychological and functional imaging data, revealing the critical role of the left ATL in exception word reading.

The impact of aging on gray matter structural covariance networks.

Previous anatomical volumetric studies have shown that healthy aging is associated with gray matter tissue loss in specific cerebral regions. However, these studies may have potentially missed critical elements of age-related brain changes, which largely exist within interrelationships among brain regions. This magnetic resonance imaging research aims to assess the effects of aging on the organization of gray matter structural covariance networks. Here, we used voxel-based morphometry on high-definition brain scans to compare the patterns of gray matter structural covariance networks that sustain different sensorimotor and high-order cognitive functions among young (n=88, mean age=23.5±3.1 years, female/male=55/33) and older (n=88, mean age=67.3±5.9 years, female/male=55/33) participants. This approach relies on the assumption that functionally correlated brain regions show correlations in gray matter volume as a result of mutually trophic influences or common experience-related plasticity. We found reduced structural association in older adults compared with younger adults, specifically in high-order cognitive networks. Major differences were observed in the structural covariance networks that subserve the following: a) the language-related semantic network, b) the executive control network, and c) the default-mode network. Moreover, these cognitive functions are typically altered in the older population. Our results indicate that healthy aging alters the structural organization of cognitive networks, shifting from a more distributed (in young adulthood) to a more localized topological organization in older individuals.

A methodological scoping review of the integration of fMRI to guide dMRI tractography. What has been done and what can be improved: A 20-year perspective.

Combining MRI modalities is a growing trend in neurosciences. It provides opportunities to investigate the brain architecture supporting cognitive functions. Integrating fMRI activation to guide dMRI tractography offers potential advantages over standard tractography methods. A quick glimpse of the literature on this topic reveals that this technique is challenging, and no consensus or "best practices" currently exist, at least not within a single document. We present the first attempt to systematically analyze and summarize the literature of 80 studies that integrated task-based fMRI results to guide tractography, over the last two decades. We report 19 findings that cover challenges related to sample size, microstructure modelling, seeding methods, multimodal space registration, false negatives/positives, specificity/validity, gray/white matter interface and more. These findings will help the scientific community (1) understand the strengths and limitations of the approaches, (2) design studies using this integrative framework, and (3) motivate researchers to fill the gaps identified. We provide references toward best practices, in order to improve the overall result's replicability, sensitivity, specificity, and validity.

Timing stroke: A review on stroke pathophysiology and its influence over time on diffusion measures.

Diffusion imaging (DWI) is considered an optimal technique to detect hyperacute cerebral ischemia and has thus enriched the clinical management of patients with suspected stroke. Researchers have taken this technique beyond with Diffusion Tensor Imaging (DTI)-extracted measures, which have been proposed as biomarkers of stroke progression. A large body of literature report on the correlates between pathophysiological events, such as cytotoxic and vasogenic edema, and diffusion changes in the brain. However, a unified picture of these changes, and their exploration as stroke pathology progression biomarkers, remains to be done. We present here a narrative review on the different pathophysiological events underlying stroke from onset until late subacute stages and its relation to different brain edema forms. Studies included in this review used either DWI and/or DTI analysis in hyperacute (<24 h), acute (1-7 days), early subacute (7-30 days) and/or late subacute (1-6 months) phase of stroke, including human and animal models. Our conclusions are that diffusion measures should be considered as a potential proxy measure for stroke neuroinflammation status, specially in early stages of the disease. Furthermore, we suggest that the choice of diffusion measures and the interpretation of their changes, in both research and clinical settings, need to be linked to the different stroke phases to account correctly for the progression, and eventual resolution, of neuroinflammation.

Validation of Videoconference Administration of Picture Description From the Western Aphasia Battery-Revised in Neurotypical Canadian French Speakers.

PURPOSE: During the COVID-19 pandemic, clinicians and researchers have increasingly used remote online assessments to pursue their activities, but mostly with tests not validated for videoconference administration. This study aims to validate the remote online administration of picture description in Canadian French neurotypical speakers and to explore the thematic unit (TU) checklist recently developed. METHOD: Spoken discourse elicited through the picture description task of the Western Aphasia Battery-Revised (WAB-R) was collected from Canadian French neurotypical speakers from Québec aged between 50 and 79 years old. Forty-seven participants completed the task in person, and 49 participants completed the task by videoconference. Videos of each discourse sample were transcribed using CHAT conventions. Microstructural variables were extracted using the CLAN (Computerized Language ANalysis) program, whereas thematic informativeness was scored for each sample using TUs. Chi-square tests were conducted to compare both groups on each TU; t tests were also performed on the total score of TUs and microstructural variables. RESULTS: Groups were matched on sex, age, and education variables. The t tests revealed no intergroup difference for the total TU score and for the microstructural variables (e.g., mean length of utterances and number of words per minute). Chi-square tests showed no significant intergroup difference for all 16 TUs. CONCLUSIONS: These findings support remote online assessment of the picnic scene of the WAB-R picture description in Canadian French neurotypical speakers. These results also validate the 16 TUs most consistently produced. The use of videoconference could promote and improve the recruitment of participants who are usually less accessible, such as people using assistive mobility technologies. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.21476961.

Picture Description of the Western Aphasia Battery Picnic Scene: Reference Data for the French Canadian Population.

PURPOSE: The main aim of this study is to provide French Canadian reference data for quantitative measures extracted from connected speech samples elicited by the Western Aphasia Battery-Revised picnic scene, a discourse task frequently used in clinical assessment of acquired language disorders. METHOD: Our sample consisted of 62 healthy French Canadian adults divided in two age groups: a 50- to 69-year-old group and a 70- to 90-year-old group. RESULTS: High interrater reliability scores were obtained for most of the variables. Most connected speech variables did not demonstrate an age effect. However, the 70- to 90-year-old group produced more repetitions than the 50- to 69-year-old group and displayed reduced communication efficiency (number of information content units per minute). CONCLUSION: These findings contribute to building a reference data set to analyze descriptive discourse production in clinical settings.

Comprehensive Analysis of Brain Volume in REM Sleep Behavior Disorder with Mild Cognitive Impairment.

BACKGROUND: Rapid-eye-movement sleep behavior disorder (RBD) is a major risk factor for Parkinson's disease and dementia with Lewy bodies. More than a third of RBD patients have mild cognitive impairment (MCI), but their specific structural brain alterations remain poorly understood. OBJECTIVE: This study aimed to investigate the local deformation and volume of gray and white matter tissue underlying MCI in RBD. METHODS: Fifty-two idiopathic RBD patients, including 17 with MCI (33%), underwent polysomnography, neuropsychological, neurological, and magnetic resonance imaging assessments. MCI diagnosis was based on a subjective complaint, cognitive impairment on the neuropsychological battery, and preserved daily functioning. Forty-one controls were also included. Deformation-based morphometry (DBM), voxel-based morphometry (VBM), and regional volume analyses of the corpus callosum and cholinergic basal forebrain were performed. Multiple regression models were also computed using anatomical, cognitive (composite z scores), and motor parameters. RESULTS: Globally, patients with MCI displayed a widespread pattern of local deformation and volume atrophy in the cortical (bilateral insula, cingulate cortex, precuneus, frontal, temporal and occipital regions, right angular gyrus, and mid-posterior segment of the corpus callosum) and subcortical (brainstem, corona radiata, basal ganglia, thalamus, amygdala, and right hippocampus) regions compared to patients without MCI (DBM) or controls (DBM and VBM). Moreover, brain deformation (DBM) in patients were associated with lower performance in attention and executive functions, visuospatial abilities, and higher motor symptoms severity. CONCLUSION: The present study identified novel brain structural alterations in RBD patients with MCI which correlated with poorer cognitive performance. These results are consistent with those reported in patients with synucleinopathies-related cognitive impairment.

The role of the left anterior temporal lobe in the semantic processing of famous faces.

Neuroimaging studies on healthy subjects have reported the involvement of the bilateral anterior temporal lobes (ATL) in recognizing known people. While the role of the right ATL in the semantic processing of known people is accepted, it is still matter of debate whether left ATL is implicated in the name retrieval or in the access to semantic information. In the present fMRI study, we modulated the level of specificity of the semantic categorization task of famous face stimuli in order to map the brain regions involved in the specific semantic processing controlling for automatic name access. Specifically, participants (n = 12, mean age = 23.0+/-1.7 years, F/M = 8/4) were asked to determine whether the stimulus photograph matched with the label of the profession category. Since the same set of stimuli was used for both specific and general conditions, contrasting these two conditions controlled for the activation due to the automatic access to the name of famous persons. Results showed that: 1) the right ATL was activated by a semantic categorization task of famous face stimuli at both general and specific level; 2) while controlling for the activation due to the automatic name retrieval, the left ATL showed increased activation during the specific categorization task; 3) the specificity of the semantic processing increased strength of connections towards the left ATL from the right lateral fusiform gyrus, devoted to the visual processing of faces, and from the right ATL. These findings support the idea of a crucial role of the left anterior temporal lobe in the processing of person-specific semantic information.

Predicting Early Post-stroke Aphasia Outcome From Initial Aphasia Severity.

Background: The greatest degree of language recovery in post-stroke aphasia takes place within the first weeks. Aphasia severity and lesion measures have been shown to be good predictors of long-term outcomes. However, little is known about their implications in early spontaneous recovery. The present study sought to determine which factors better predict early language outcomes in individuals with post-stroke aphasia. Methods: Twenty individuals with post-stroke aphasia were assessed <72 h (acute) and 10-14 days (subacute) after stroke onset. We developed a composite score (CS) consisting of several linguistic sub-tests: repetition, oral comprehension and naming. Lesion volume, lesion load and diffusion measures [fractional anisotropy (FA) and axial diffusivity (AD)] from both arcuate fasciculi (AF) were also extracted using MRI scans performed at the same time points. A series of regression analyses were performed to predict the CS at the second assessment. Results: Among the diffusion measures, only FA from right AF was found to be a significant predictor of early subacute aphasia outcome. However, when combined in two hierarchical models with FA, age and either lesion load or lesion size, the initial aphasia severity was found to account for most of the variance (R 2 = 0.678), similarly to the complete models (R 2 = 0.703 and R 2 = 0.73, respectively). Conclusions: Initial aphasia severity was the best predictor of early post-stroke aphasia outcome, whereas lesion measures, though highly correlated, show less influence on the prediction model. We suggest that factors predicting early recovery may differ from those involved in long-term recovery.