Progression of Aphasia Severity in the Chronic Stages of Stroke

Aphasia severity and factors predicting language recovery in the chronic stage of stroke

BACKGROUND

It is assumed that language impairments post-stroke do not show much improvement after the phase of spontaneous recovery, especially in the chronic stage. Several studies have reported language recovery and factors influencing it in the acute stages of stroke. There is limited literature focusing on language recovery in the chronic stages of stroke, especially in the Indian population, and the demographic, lesion- and aphasia-related factors that contribute towards language recovery in the chronic stages are poorly understood.

AIMS

To assess changes in aphasia severity at two time points in the chronic stage and to identify the factors (demographic, lesion- and aphasia-related) predicting language recovery in chronic stroke aphasia.

METHODS & PROCEDURES

In this cross-sectional study, 22 individuals with chronic stroke aphasia underwent the baseline language assessment (T1) using Western Aphasia Battery (WAB) at least 2 or more months post-onset. A follow-up language assessment (T2) for the same individuals was conducted 3-12 months post-baseline assessment. The mean age of the participant group was 48.18 years (SD = 13.05) with a corresponding mean year of education of 9.18 (SD = 5.81). 81.8% of the participants (N = 18) were male and majority of them belonged to the lower middle socio-economic status (N = 9, 40%).

OUTCOMES & RESULTS

There was a significant change in mean language subdomain and aphasia quotient scores of WAB between two time points (p = 0.000). The majority showed a significant improvement in their AQ scores (WAB-SEM 2.5) in the absence of speech therapy. Socio-economic status (p = 0.005) and aphasia severity (AQ1) at baseline (p = 0.000) were significant in predicting language recovery.

CONCLUSIONS & IMPLICATIONS

Significant language recovery occurs in the chronic stage of stroke, which is predicted by socio-economic status and aphasia severity at baseline assessment. This study will provide clinicians with an insight into language recovery in chronic stroke aphasia and help serve as a guide for evidence-based prognostic statements. These findings encourage patients with aphasia to seek speech and language therapy in the chronic stage of stroke.

WHAT THIS PAPER ADDS

What is already known on the subject A number of studies have reported language recovery occurring in the acute stages of post-stroke aphasia and the factors predicting it. There is limited literature focusing on language recovery occurring between two time points in the chronic stages of stroke especially in the Indian population, and the demographic, lesion- and aphasia-related factors that contribute towards it are poorly understood. What this paper adds to the existing knowledge Language recovery occurs in the chronic stage of stroke aphasia and is predicted by socio-economic status and aphasia severity at baseline assessment. In our study, language recovery was found to take place even in the absence of formal speech and language intervention, thus indicating that spontaneous recovery continues well into the chronic stage as well. What are the potential or actual clinical implications of this study? This study will provide clinicians with an understanding of the language recovery occurring in chronic stroke aphasia as well as the factors influencing recovery, thus serving as a guide for evidence-based prognostic statements. Evidence of language recovery in the chronic stage will encourage patients to attend intensive speech and language therapy in this stage resulting in significant improvement in language functions.

White Matter Hyperintensity Load Independent From the Stroke Lesion Is Associated With Chronic Aphasia Severity and Treatment Outcome

BACKGROUND

Although many studies have suggested that white matter hyperintensity (WMH) severity predicts naming and aphasia severity in chronic poststroke aphasia, there are inconsistencies in the literature. WMHs are typically symmetrical in neurotypical controls, and measuring WMH in the contralateral hemisphere is likely the best option to estimate brain health independently from the stroke lesion and avoid measurement contamination from stroke-related gliosis. In this study, we aimed to clarify the discrepancies in the literature by testing whether WMH rating methods are related to clinical outcomes.

METHODS

Ninety-five participants with chronic aphasia at least 12 months after their left-hemisphere stroke completed a baseline Western Aphasia Battery and the Philadelphia Naming Test. All participants then underwent 6 weeks of phonological and semantic naming treatments focused on improving lexical processing, and the Philadelphia Naming Test was readministered immediately following treatment. Using the Fazekas scale, WMH severity was independently rated on the whole brain and the right hemisphere only. Their relationship of WMH behavior was calculated by accounting for age, lesion volume, time poststroke, years of education, and sex.

RESULTS

There were significant positive correlations between whole-brain and right-hemisphere ratings of WMH, but Wilcoxon signed-rank tests revealed that whole-brain ratings were consistently higher (whole brain M=3.337, right hemisphere M=2.899; P<0.001). Right hemisphere ratings were more strongly correlated with behavioral measures. There were significant negative correlations between all WMH ratings and behavior at baseline (Western Aphasia Battery Aphasia Quotient and Philadelphia Naming Test) except for whole brain periventricular ratings. However, only right-hemisphere periventricular WMH was significantly associated with therapy-related naming improvements (r=-0.226, R2=0.05, P=0.044).

CONCLUSIONS

Given the regional effect of the stroke lesion, whole-brain ratings can overestimate the WMH burden and thus reduce the accuracy in evaluating small vessel disease effects on stroke recovery and aphasia severity, particularly therapy-related neuroplasticity. This is an important detail that should be considered in mechanistic studies of small vessel disease, brain health, and stroke recovery.

TEleRehabilitation foR Aphasia (TERRA) phase II trial design

Background and purpose

Despite comprehensive evidence that supports the utility of aphasia therapy in persons with chronic (≥6 months) stroke-induced aphasia, the amount of therapy provided to patients in the United States is typically far less than what is likely necessary to maximize recovery. Two potential contributors to this discrepancy are limited access to rehabilitation services due to the availability of providers and logistical difficulties with transportation. One way to increase access to aphasia therapy is to rely on telerehabilitation.

Methods

The TEleRehabilitation foR Aphasia (TERRA) trial is a prospective, randomized, rater-blinded, multicenter phase II non-inferiority trial to evaluate telerehabilitation for aphasia therapy in persons with chronic post-stroke aphasia. Participants are randomized (1:1) to receive either aphasia remote therapy or in-clinic therapy for 30 total days of treatment (15 days of a semantically focused approach and 15 days of a phonologically focused approach) for 45 min per day. A total of 100 adults (ages 21-80) with a history of left hemisphere ischemic or hemorrhagic stroke incurred at least 12 months prior to study enrollment will be randomized. The trial will be conducted at the clinical research facilities at two sites: the Medical University of South Carolina and the University of South Carolina.

Conclusions

This paper details the design of the TERRA trial, which aims to test whether aphasia therapy delivered by a remote speech-language pathologist through videoconferencing (i.e., via telerehabilitation) is not clinically worse than in-clinic therapy for individuals with chronic post-stroke aphasia to provide an opportunity to move to a definitive phase III trial.

The Aphasia Recovery Cohort, an open-source chronic stroke repository

Sharing neuroimaging datasets enables reproducibility, education, tool development, and new discoveries. Neuroimaging from many studies are publicly available, providing a glimpse into progressive disorders and human development. In contrast, few stroke studies are shared, and these datasets lack longitudinal sampling of functional imaging, diffusion imaging, as well as the behavioral and demographic data that encourage novel applications. This is surprising, as stroke is a leading cause of disability, and acquiring brain imaging is considered standard of care. The first release of the Aphasia Recovery Cohort includes imaging data, demographics and behavioral measures from 230 chronic stroke survivors who experienced aphasia. We also share scripts to illustrate how the imaging data can predict impairment. In conclusion, recent advances in machine learning thrive on large, diverse datasets. Clinical data sharing can contribute to improvements in automated detection of brain injury, identification of white matter hyperintensities, measures of brain health, and prognostic abilities to guide care.

Under pressure: the interplay of hypertension and white matter hyperintensities with cognition in chronic stroke aphasia

While converging research suggests that increased white matter hyperintensity load is associated with poorer cognition, and the presence of hypertension is associated with increased white matter hyperintensity load, the relationship among hypertension, cognition and white matter hyperintensities is not well understood. We sought to determine the effect of white matter hyperintensity burden on the relationship between hypertension and cognition in individuals with post-stroke aphasia, with the hypothesis that white matter hyperintensity load moderates the relationship between history of hypertension and cognitive function. Health history, Fazekas scores for white matter hyperintensities and Wechsler Adult Intelligence Scale Matrix Reasoning subtest scores for 79 people with aphasia collected as part of the Predicting Outcomes of Language Rehabilitation study at the Center for the Study of Aphasia Recovery at the University of South Carolina and the Medical University of South Carolina were analysed retrospectively. We found that participants with a history of hypertension had increased deep white matter hyperintensity severity (P < 0.001), but not periventricular white matter hyperintensity severity (P = 0.116). Moderation analysis revealed that deep white matter hyperintensity load moderates the relationship between high blood pressure and Wechsler Adult Intelligence Scale scores when controlling for age, education, aphasia severity and lesion volume. The interaction is significant, showing that a history of high blood pressure and severe deep white matter hyperintensities together are associated with poorer Matrix Reasoning scores. The overall model explains 41.85% of the overall variation in Matrix Reasoning score in this group of participants. These findings underscore the importance of considering cardiovascular risk factors in aphasia treatment, specifically hypertension and its relationship to brain health in post-stroke cognitive function.

Regional brain aging: premature aging of the domain general system predicts aphasia severity

Premature brain aging is associated with poorer cognitive reserve and lower resilience to injury. When there are focal brain lesions, brain regions may age at different rates within the same individual. Therefore, we hypothesize that reduced gray matter volume within specific brain systems commonly associated with language recovery may be important for long-term aphasia severity. Here we show that individuals with stroke aphasia have a premature brain aging in intact regions of the lesioned hemisphere. In left domain-general regions, premature brain aging, gray matter volume, lesion volume and age were all significant predictors of aphasia severity. Increased brain age following a stroke is driven by the lesioned hemisphere. The relationship between brain age in left domain-general regions and aphasia severity suggests that degradation is possible to specific brain regions and isolated aging matters for behavior.

Predicting Language Function Post-Stroke: A Model-Based Structural Connectivity Approach

BACKGROUND

The prediction of post-stroke language function is essential for the development of individualized treatment plans based on the personal recovery potential of aphasic stroke patients.

OBJECTIVE

To establish a framework for integrating information on connectivity disruption of the language network based on routinely collected clinical magnetic resonance (MR) images into Random Forest modeling to predict post-stroke language function.

METHODS

Language function was assessed in 76 stroke patients from the Non-Invasive Repeated Therapeutic Stimulation for Aphasia Recovery trial, using the Token Test (TT), Boston Naming Test (BNT), and Semantic Verbal Fluency (sVF) Test as primary outcome measures. Individual infarct masks were superimposed onto a diffusion tensor imaging tractogram reference set to calculate Change in Connectivity scores of language-relevant gray matter regions as estimates of structural connectivity disruption. Multivariable Random Forest models were derived to predict language function.

RESULTS

Random Forest models explained moderate to high amount of variance at baseline and follow-up for the TT (62.7% and 76.2%), BNT (47.0% and 84.3%), and sVF (52.2% and 61.1%). Initial language function and non-verbal cognitive ability were the most important variables to predict language function. Connectivity disruption explained additional variance, resulting in a prediction error increase of up to 12.8% with variable omission. Left middle temporal gyrus (12.8%) and supramarginal gyrus (9.8%) were identified as among the most important network nodes.

CONCLUSION

Connectivity disruption of the language network adds predictive value beyond lesion volume, initial language function, and non-verbal cognitive ability. Obtaining information on connectivity disruption based on routine clinical MR images constitutes a significant advancement toward practical clinical application.

Recovery of gestures for persons with severe non-fluent aphasia and limb apraxia: A long-term follow-up study

Persons with severe non-fluent aphasia would benefit from using gestures to substitute for their absent powers of speech. The use of gestures, however, is challenging for persons with aphasia and concomitant limb apraxia. Research on the long-term recovery of gestures is scant, and it is unclear whether gesture performance can show recovery over time. This study evaluated the recovery of emblems and tool use pantomimes of persons with severe non-fluent aphasia and limb apraxia after a left hemisphere stroke. The Florida Apraxia Screening Test-Revised (FAST-R) was used for measurements. The test includes 30 gestures to be performed (i) after an oral request, (ii) with the aid of a pictorial cue, or (iii) as an imitation. The gestures were rated on their degree of comprehensibility. The comprehensibility of gestures after an oral request improved significantly in five out of seven participants between the first (1-3 months after the stroke) and the last (3 years after) examination. Improvement continued for all five in the period between six months and three years. The imitation model did improve the comprehensibility of gestures for all participants, whereas the pictorial cue did so just slightly. The skill of producing gestures can improve even in the late phase post-stroke. Because of this potential, we suggest that gesture training should be systematically included in the rehabilitation of communication for persons with severe non-fluent aphasia.

Efficacy of different rehabilitation therapies on post-stroke aphasia patients: A network meta-analysis

BACKGROUND

Although several rehabilitation interventions are effective in post-stroke aphasia (PSA), the efficacy of different rehabilitation interventions compared to each other remains controversial. Here, we aimed to compare the effectiveness of varying rehabilitation interventions in PSA.

METHODS

Randomized controlled trials on 8 kinds of rehabilitation interventions to improve speech function in patients with PSA were searched by computer from 10 databases, including PubMed, Web of Science, Cochrane, OVID, CINAHL, Embase, CNKI, WanFang, CBM, and VIP. The search scope was from the establishment of the database to August 2023. The literature screening, extraction of basic information, and quality assessment of the literature were conducted independently by 2 researchers. Network meta-analysis (NMA) was performed using Stata 17.0 software.

RESULTS

Fifty-four studies involving 2688 patients with PSA were included. The results of NMA showed that: ① in terms of improving the severity of aphasia, the therapeutic effects of repetitive transcranial magnetic stimulation were the most significant; ② motor imagery therapy was the most effective in improving spontaneous speech, repetition, and naming ability; ③ in terms of improving listening comprehension ability, the therapeutic effects of mirror neuron therapy was the most significant.

CONCLUSION

The 8 rehabilitation interventions have different focuses in improving the speech function of PSA patients, and the clinical therapists can select the optimal rehabilitation interventions in a targeted manner according to the results of this NMA and the patients' conditions and other relevant factors.

A Review of Poststroke Aphasia Recovery and Treatment Options

Poststroke aphasia, which impacts expressive and receptive communication, can have detrimental effects on the psychosocial well-being and the quality of life of those affected. Aphasia recovery is multidimensional and can be influenced by several baseline, stroke-related, and treatment-related factors, including preexisting cerebrovascular conditions, stroke size and location, and amount of therapy received. Importantly, aphasia recovery can continue for many years after aphasia onset. Behavioral speech and language therapy with a speech-language pathologist is the most common form of aphasia therapy. In this review, the authors also discuss augmentative treatment methodologies, collaborative goal setting frameworks, and recommendations for future research.

Progressive lesion necrosis is related to increasing aphasia severity in chronic stroke

BACKGROUND

Volumetric investigations of cortical damage resulting from stroke indicate that lesion size and shape continue to change even in the chronic stage of recovery. However, the potential clinical relevance of continued lesion growth has yet to be examined. In the present study, we investigated the prevalence of lesion expansion and the relationship between expansion and changes in aphasia severity in a large sample of individuals in the chronic stage of aphasia recovery.

METHODS

Retrospective structural MRI scans from 104 S survivors with at least 2 observations (k = 301 observations; mean time between scans = 31 months) were included. Lesion demarcation was performed using an automated lesion segmentation software and lesion volumes at each timepoint were subsequently calculated. A linear mixed effects model was conducted to investigate the effect of days between scan on lesion expansion. Finally, we investigated the association between lesion expansion and changes on the Western Aphasia Battery (WAB) in a group of participants assessed and scanned at 2 timepoints (N = 54) using a GLM.

RESULTS

Most participants (81 %) showed evidence of lesion expansion. The mixed effects model revealed lesion volumes significantly increase, on average, by 0.02 cc each day (7.3 cc per year) following a scan (p < 0.0001). Change on language performance was significantly associated with change in lesion volume (p = 0.025) and age at stroke (p = 0.031). The results suggest that with every 10 cc increase in lesion size, language performance decreases by 0.9 points, and for every 10-year increase in age at stroke, language performance decreases by 1.9 points.

CONCLUSIONS

The present study confirms and extends prior reports that lesion expansion occurs well into the chronic stage of stroke. For the first time, we present evidence that expansion is predictive of longitudinal changes in language performance in individuals with aphasia. Future research should focus on the potential mechanisms that may lead to necrosis in areas surrounding the chronic stroke lesion.

The effectiveness and safety of noninvasive brain stimulation technology combined with speech training on aphasia after stroke: A systematic review and meta-analysis

BACKGROUND

Although the effectiveness of noninvasive brain stimulation (NIBS) technology in assisting rehabilitation is widely recognized, its therapeutic efficacy in patients with poststroke aphasia (PSA) requires further validation. Here, we aimed to explore the efficacy and safety of the NIBS technique combined with speech training in PSA by traditional Meta-analysis and to compare the intervention effects of the 2 NIBS techniques by Network meta-analysis.

METHODS

Randomized controlled trials of the NIBS technique combined with speech training for treating PSA in 9 databases, including Web of Science, PubMed, and CNKI, and 2 clinical trial registries were searched by computer. Literature screening was performed using EndNote X9 software, and data analysis and presentation of results were performed using RevMan 5.4.1 and Stata 17.0 software.

RESULTS

Screening yielded 17 studies with 1013 patients with PSA. Meta-analysis showed that aphasia quotient scores were higher in the intervention group than in the control group [standardized mean difference (SMD) = 1.06, 95% confidence interval (CI) (0.63, 1.49), Z = 4.80, P < .00001]; Western aphasia battery scores on all 4 subscales were higher than those of the control group, the spontaneous language score is [SMD = 0.62, 95% CI (0.46, 0.78), Z = 7.52, P < .00001], the listening comprehension score is [SMD = 0.46, 95% CI (0.30, 0.62), Z = 5.62, P < .00001], the repetition score is [SMD = 1.14, 95% CI (0.59, 1.70), Z = 4.04, P < .0001], the naming score is [SMD = 1.06, 95% CI (0.79, 1.32), Z = 7.85, P < .00001]; The effective rate of the intervention group was higher than that of the control group [odd ratio = 4.19, 95% CI (2.39, 7.37), Z = 4.99, P < .00001]. The results of the Network meta-analysis showed that the best probability ranking of the 2 NIBS techniques combined with speech training in improving aphasia quotient scores was repetitive transcranial magnetic stimulation group (92.2%) > transcranial direct current stimulation group (55.7%). Regarding safety, it was not found that the NIBS technique combined with speech training to treat PSA increases the risk of adverse reactions.

CONCLUSION

The NIBS technique combined with speech training can effectively improve the recovery of language function in PSA patients with minimal adverse effects, and the clinic can give priority to r TMS combined with speech training in treating PSA.

Insights gained over 60 years on factors shaping post-stroke aphasia recovery: A commentary on Vignolo (1964)

Aphasia is an acquired language disorder resulting from brain injury, including strokes which is the most common etiology, neurodegenerative diseases, tumors, traumatic brain injury, and resective surgery. Aphasia affects a significant portion of stroke survivors, with approximately one third experiencing its debilitating effects in the long term. Despite its challenges, there is growing evidence that recovery from aphasia is possible, even in the chronic phase of stroke. Sixty years ago, Vignolo (1964) outlined the primary challenges confronted by researchers in this field. These challenges encompassed the absence of an objective evaluation of language difficulties, the scarcity of evidence regarding spontaneous aphasia recovery, and the presence of numerous variables that could potentially influence the process of aphasia recovery. In this paper, we discuss the remarkable progress that has been made in the assessment of language and communication in aphasia as well as in understanding the factors influencing post-stroke aphasia recovery.

Investigating Aphasia Recovery: Demographic and Clinical Factors

Post-stroke language recovery remains one of the main unresolved topics in the field of aphasia. In recent years, there have been efforts to identify specific factors that could potentially lead to improved language recovery. However, the exact relationship between the recovery of particular language functions and possible predictors, such as demographic or lesion variables, is yet to be fully understood. In the present study, we attempted to investigate such relationships in 42 patients with aphasia after left hemisphere stroke, focusing on three language domains: auditory comprehension, naming and speech fluency. Structural imaging data were also obtained for the identification of the lesion sites. According to our findings, patients demonstrated an overall improvement in all three language domains, while no demographic factor significantly contributed to aphasia recovery. Interestingly, specific lesion loci seemed to have a differential effect on language performance, depending on the time of testing (i.e., acute/subacute vs. chronic phase). We argue that this variability concerning lesion-deficit associations reflects the dynamic nature of aphasia and further discuss possible explanations in the framework of neuroplastic changes during aphasia recovery.

Longitudinal Progression of White Matter Hyperintensity Severity in Chronic Stroke Aphasia

Objective

To determine whether longitudinal progression of small vessel disease in chronic stroke survivors is associated with longitudinal worsening of chronic aphasia severity.

Design

A longitudinal retrospective study. Severity of white matter hyperintensities (WMHs) as a marker for small vessel disease was assessed on fluid-attenuated inversion recovery (FLAIR) scans using the Fazekas scale, with ratings for deep WMHs (DWMHs) and periventricular WMHs (PVHs).

Setting

University research laboratories.

Participants

This study includes data from 49 chronic stroke survivors with aphasia (N=49; 15 women, 34 men, age range=32-81 years, >6 months post-stroke, stroke type: [46 ischemic, 3 hemorrhagic], community dwelling). All participants completed the Western Aphasia Battery-Revised (WAB) and had FLAIR scans at 2 timepoints (average years between timepoints: 1.87 years, SD=3.21 years).

Interventions

Not applicable.

Main Outcome Measures

Change in white matter hyperintensity severity (calculated using the Fazekas scale) and change in aphasia severity (difference in Western Aphasia Battery scores) were calculated between timepoints. Separate stepwise regression models were used to identify predictors of WMH severity change, with lesion volume, age, time between timepoints, body mass index (BMI), and presence of diabetes as independent variables. Additional stepwise regression models investigated predictors of change in aphasia severity, with PVH change, DWMH change, lesion volume, time between timepoints, and age as independent predictors.

Results

22.5% of participants (11/49) had increased WMH severity. Increased BMI was associated with increases in PVH severity (P=.007), whereas the presence of diabetes was associated with increased DWMH severity (P=.002). Twenty-five percent of participants had increased aphasia severity which was significantly associated with increased severity of PVH (P<.001, 16.8% variance explained).

Conclusion

Increased small vessel disease burden is associated with contributing to chronic changes in aphasia severity. These findings support the idea that good cardiovascular risk factor control may play an important role in the prevention of long-term worsening of aphasic symptoms.

Word Repetition Paired With Startling Stimuli Decreases Aphasia and Apraxia Severity in Severe-to-Moderate Stroke: A Stratified, Single-Blind, Randomized, Phase 1 Clinical Trial

PURPOSE

This prospective, single-blinded, parallel, stratified, randomized clinical trial via telehealth aimed to investigate the impact of Startle Adjuvant Rehabilitation Therapy (START) on aphasia, apraxia of speech (AOS), and quality of life in individuals with chronic stroke. The study hypothesized that START would have a greater effect on AOS-related measures and more severe individuals.

METHOD

Forty-two participants with poststroke aphasia, AOS, or both were randomly assigned to the START or control group. Both groups received 77-dB GET READY and GO cues during a word repetition task for three 1-hr sessions on consecutive days. The START group additionally received 105-dB white noise GO cues during one third of trials. The Western Aphasia Battery-Revised, Apraxia Battery for Adults, Stroke Impact Scale, and Communication Outcomes After Stroke scale were administered at Day 1, Day 5, and 1-month follow-up.

RESULTS

START improved performance on some subtests of the Western Aphasia Battery (Comprehension, Repetition, Reading) and measures of AOS (Diadochokinetic Rate, Increasing Word Length) in individuals with moderate/severe aphasia, whereas moderate/severe controls saw no changes. Individuals with mild aphasia receiving START had improved Reading, whereas mild controls saw improved Comprehension. The START group had increased mood and perceived communication recovery by Day 5, whereas controls saw no changes in quality of life.

CONCLUSIONS

This study is the first to evaluate the impact of training with startling acoustic stimuli on clinical measures of aphasia and AOS. Our findings suggest START can enhance both nontrained speech production and receptive speech tasks in moderate/severe aphasia, possibly by reducing poststroke cortical inhibition. Our findings should be considered carefully, as our limitations include small effect sizes, within-group variability, and low completion rates for quality-of-life assessments and follow-up visits. Future studies should explore a mechanism of action, conduct larger and longer Phase 2 clinical trials, and evaluate long-term retention.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.24093519.

Dynamic network properties of the superior temporal gyrus mediate the impact of brain age gap on chronic aphasia severity

Brain structure deteriorates with aging and predisposes an individual to more severe language impairments (aphasia) after a stroke. However, the underlying mechanisms of this relation are not well understood. Here we use an approach to model brain network properties outside the stroke lesion, network controllability, to investigate relations among individualized structural brain connections, brain age, and aphasia severity in 93 participants with chronic post-stroke aphasia. Controlling for the stroke lesion size, we observe that lower average controllability of the posterior superior temporal gyrus (STG) mediates the relation between advanced brain aging and aphasia severity. Lower controllability of the left posterior STG signifies that activity in the left posterior STG is less likely to yield a response in other brain regions due to the topological properties of the structural brain networks. These results indicate that advanced brain aging among individuals with post-stroke aphasia is associated with disruption of dynamic properties of a critical language-related area, the STG, which contributes to worse aphasic symptoms. Because brain aging is variable among individuals with aphasia, our results provide further insight into the mechanisms underlying the variance in clinical trajectories in post-stroke aphasia.

Perceived Factors That Facilitate or Prevent the Use of Speech-Generating Devices in Bilingual Individuals With Aphasia

PURPOSE

The aim of this study was to explore practicing speech-language pathologists' (SLPs') perceptions of factors that could facilitate or prevent the use of speech-generating devices (SGDs) in bilingual individuals with aphasia. Specifically, this exploratory study sought to identify the facilitators and barriers to SGD use in individuals with culturally and linguistically diverse backgrounds.

METHOD

An online survey was distributed to SLPs through an e-mail listserv and social media of an augmentative and alternative communication company. This article focused on the results of the survey items related to (a) the presence of bilingual individuals with aphasia on an SLP's caseload, (b) training related to SGD or bilingual aphasia, and (c) barriers and facilitators to SGD use. A thematic analysis was conducted to analyze the barriers and facilitators to SGD use reported by the respondents.

RESULTS

A total of 274 SLPs who met the inclusion criteria had experience in implementing SGD for people with aphasia. Regarding relevant training, our results indicated that very few SLPs received bilingual aphasia intervention training (17.22%) or bilingual SGD training (0.56%) in graduate school. The results from our thematic analysis revealed four major themes of barriers and facilitators to SGD use, including (a) hardware and software, (b) cultural and language content, (c) SLP's cultural and linguistic competency, and (d) resources.

CONCLUSIONS

Practicing SLPs reported several barriers to SGD use in bilinguals with aphasia. Most notably, language barriers for monolingual SLPs were seen as the greatest barrier to language recovery in individuals with aphasia whose primary language is not English. Several other barriers were consistent with previous research, such as financial factors and insurance disparities. The top three most important factors that facilitate SGD use in bilinguals with aphasia, as identified by the respondents, include user-friendly symbol organization, personalized words, and ease of programming.

Diabetes, brain health, and treatment gains in post-stroke aphasia

In post-stroke aphasia, language improvements following speech therapy are variable and can only be partially explained by the lesion. Brain tissue integrity beyond the lesion (brain health) may influence language recovery and can be impacted by cardiovascular risk factors, notably diabetes. We examined the impact of diabetes on structural network integrity and language recovery. Seventy-eight participants with chronic post-stroke aphasia underwent six weeks of semantic and phonological language therapy. To quantify structural network integrity, we evaluated the ratio of long-to-short-range white matter fibers within each participant's whole brain connectome, as long-range fibers are more susceptible to vascular injury and have been linked to high level cognitive processing. We found that diabetes moderated the relationship between structural network integrity and naming improvement at 1 month post treatment. For participants without diabetes (n = 59), there was a positive relationship between structural network integrity and naming improvement (t = 2.19, p = 0.032). Among individuals with diabetes (n = 19), there were fewer treatment gains and virtually no association between structural network integrity and naming improvement. Our results indicate that structural network integrity is associated with treatment gains in aphasia for those without diabetes. These results highlight the importance of post-stroke structural white matter architectural integrity in aphasia recovery.

A simple smartphone-aided program to support meaningful occupation in people with severe neuro-motor and speech disabilities

We assessed a simple smartphone-aided program to help three participants with severe neuro-motor and speech disabilities access preferred songs, call or send messages to distant partners, and call the caregiver. The program relied on the use of a smartphone, five cards with identification tags, and a mini speaker. The participants could select one of the cards (engagement options) by touching it with the smartphone. Using the program, all participants managed to access songs, reach partners, and call the caregiver independently and engaged in the related forms of leisure and communication/interaction throughout the 10-min sessions available. The results suggest that the program might be a valuable aid for people with severe neuro-motor and speech disabilities.

Comparing the brain-behaviour relationship in acute and chronic stroke aphasia

In stroke aphasia, lesion volume is typically associated with aphasia severity. Although this relationship is likely present throughout recovery, different factors may affect lesion volume and behaviour early into recovery (acute) and in the later stages of recovery (chronic). Therefore, studies typically separate patients into two groups (acute/chronic), and this is often accompanied with arguments for and against using data from acute stroke patients over chronic. However, no comprehensive studies have provided strong evidence of whether the lesion-behaviour relationship early in recovery is comparable to later in the recovery trajectory. To that end, we investigated two aims: (i) whether lesion data from acute and chronic patients yield similar results in region-based lesion-symptom mapping analyses and (ii) if models based on one timepoint accurately predict the other. Lesions and aphasia severity scores from acute (N = 63) and chronic (N = 109) stroke survivors with aphasia were entered into separate univariate region-based lesion-symptom mapping analyses. A support vector regression model was trained on lesion data from either the acute or chronic data set to give an estimate of aphasia severity. Four model-based analyses were conducted: trained on acute/chronic using leave-one-out, tested on left-out behaviour or trained on acute/chronic to predict the other timepoint. Region-based lesion-symptom mapping analyses identified similar but not identical regions in both timepoints. All four models revealed positive correlations between actual and predicted Western Aphasia Battery-Revised aphasia-quotient scores. Lesion-to-behaviour predictions were almost equivalent when comparing within versus across stroke stage, despite differing lesion size/locations and distributions of aphasia severity between stroke timepoints. This suggests that research investigating the brain-behaviour relationship including subsets of patients from only one timepoint may also be applicable at other timepoints, although it is important to note that these comparable findings may only be seen using broad measures such as aphasia severity, rather than those aimed at identifying more specific deficits. Subtle differences found between timepoints may also be useful in understanding the nature of lesion volume and aphasia severity over time. Stronger correlations found when predicting acute behaviour (e.g. predicting acute: r = 0.6888, P < 0.001, predicting chronic r = 0.5014, P < 0.001) suggest that the acute lesion/perfusion patterns more accurately capture the critical changes in underlying vascular territories. Differences in critical brain regions between timepoints may shed light on recovery patterns. Future studies could focus on a longitudinal design to compare acute and chronic patients in a more controlled manner.

Advanced Brain Age and Chronic Poststroke Aphasia Severity

BACKGROUND AND OBJECTIVES

Chronic poststroke language impairment is typically worse in older individuals or those with large stroke lesions. However, there is unexplained variance that likely depends on intact tissue beyond the lesion. Brain age is an emerging concept, which is partially independent from chronologic age. Advanced brain age is associated with cognitive decline in healthy older adults; therefore, we aimed to investigate the relationship with stroke aphasia. We hypothesized that advanced brain age is a significant factor associated with chronic poststroke language impairments, above and beyond chronologic age, and lesion characteristics.

METHODS

This cohort study retrospectively evaluated participants from the Predicting Outcomes of Language Rehabilitation in Aphasia clinical trial (NCT03416738), recruited through local advertisement in South Carolina (US). Primary inclusion criteria were left hemisphere stroke and chronic aphasia (≥12 months after stroke). Participants completed baseline behavioral testing including the Western Aphasia Battery-Revised (WAB-R), Philadelphia Naming Test (PNT), Pyramids and Palm Trees Test (PPTT), and Wechsler Adult Intelligence Scale Matrices subtest, before completing 6 weeks of language therapy. The PNT was repeated 1 month after therapy. We leveraged modern neuroimaging techniques to estimate brain age and computed a proportional difference between chronologic age and estimated brain age. Multiple linear regression models were used to evaluate the relationship between proportional brain age difference (PBAD) and behavior.

RESULTS

Participants (N = 93, 58 males and 35 females, average age = 61 years) had estimated brain ages ranging from 14 years younger to 23 years older than chronologic age. Advanced brain age predicted performance on semantic tasks (PPTT) and language tasks (WAB-R). For participants with advanced brain aging (n = 47), treatment gains (improvement on the PNT) were independently predicted by PBAD (T = -2.0474, p = 0.0468, 9% of variance explained).

DISCUSSION

Through the application of modern neuroimaging techniques, advanced brain aging was associated with aphasia severity and performance on semantic tasks. Notably, therapy outcome scores were also associated with PBAD, albeit only among participants with advanced brain aging. These findings corroborate the importance of brain age as a determinant of poststroke recovery and underscore the importance of personalized health factors in determining recovery trajectories, which should be considered during the planning or implementation of therapeutic interventions.

Predicting Outcomes of Language Rehabilitation: Prognostic Factors for Immediate and Long-Term Outcomes After Aphasia Therapy

BACKGROUND

Aphasia therapy is an effective approach to improve language function in chronic aphasia. However, it remains unclear what prognostic factors facilitate therapy response at the individual level. Here, we utilized data from the POLAR (Predicting Outcomes of Language Rehabilitation in Aphasia) trial to (a) determine therapy-induced change in confrontation naming and long-term maintenance of naming gains and (b) examine the extent to which aphasia severity, age, education, time postonset, and cognitive reserve predict naming gains at 1 week, 1 month, and 6 months posttherapy.

METHOD

A total of 107 participants with chronic (≥ 12 months poststroke) aphasia underwent extensive case history, cognitive-linguistic testing, and a neuroimaging workup prior to receiving 6 weeks of impairment-based language therapy. Therapy-induced change in naming performance (measured as raw change on the 175-item Philadelphia Naming Test [PNT]) was assessed 1 week after therapy and at follow-up time points 1 month and 6 months after therapy completion. Change in naming performance over time was evaluated using paired t tests, and linear mixed-effects models were constructed to examine the association between prognostic factors and therapy outcomes.

RESULTS

Naming performance was improved by 5.9 PNT items (Cohen's d = 0.56, p < .001) 1 week after therapy and by 6.4 (d = 0.66, p < .001) and 7.5 (d = 0.65, p < .001) PNT items at 1 month and 6 months after therapy completion, respectively. Aphasia severity emerged as the strongest predictor of naming improvement recovery across time points; mild (ß = 5.85-9.02) and moderate (ß = 9.65-11.54) impairment predicted better recovery than severe (ß = 1.31-3.37) and very severe (ß = 0.20-0.32) aphasia. Age was an emergent prognostic factor for recovery 1 month (ß = -0.14) and 6 months (ß = -0.20) after therapy, and time postonset (ß = -0.05) was associated with retention of naming gains at 6 months posttherapy.

CONCLUSIONS

These results suggest that therapy-induced naming improvement is predictable based on several easily measurable prognostic factors. Broadly speaking, these results suggest that prognostication procedures in aphasia therapy can be improved and indicate that personalization of therapy is a realistic goal in the near future.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.22141829.

Effect of an extension speech training program based on Chinese idioms in patients with post-stroke non-fluent aphasia: A randomized controlled trial

BACKGROUND

Chinese idioms have potential to act as preliminary training material in studies on post-stroke aphasia.

OBJECTIVE

To explore an extension speech training program that takes Chinese idioms as context and expands them into characters, words, sentences and paragraphs and evaluate the effects of this program in patients with post-stroke non-fluent aphasia.

METHODS

This was a randomized controlled trial. We recruited patients with post-stroke non-fluent aphasia from the Renmin Hospital of Wuhan University from January 2021 to January 2022. Participants were randomly assigned to group I and group II. Patients in group I had treatment with extension speech training based on Chinese idioms, and those in group II had treatment with conventional speech rehabilitation training. The training period in both groups was 40 min daily for 2 weeks.

RESULTS

A total of 70 patients (group I, n = 34; and group II, n = 36) completed the trial and were analyzed according to protocol. There were no significant differences in baseline values between both groups. After intervention, the scores of oral expression, comprehension, and reading in the Aphasia Battery Of Chinese scale and the scores of the Comprehensive Activities of Daily Living questionnaire significantly improved in both groups (P <0.05), with group I benefiting more (P <0.05).

CONCLUSION

This extension speech training program based on Chinese idioms can improve the language function and daily communication ability of the patients with post-stroke non-fluent aphasia.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2000031825.

Experiences of participating in group-based rehabilitation programmes: A qualitative study of community-dwelling adults with post-stroke aphasia

BACKGROUND

People with post-stroke aphasia tend to have smaller social networks, a higher risk of depression and poorer health-related quality of life than those who do not have aphasia after stroke. Stroke-specific or general rehabilitation programmes offered by community-based organizations are commonly group-based and involve discussions among group members with or without stroke. Research has shown that people with post-stroke aphasia may be unable to participate fully in verbal sharing of experiences and exchange of thoughts.

AIMS

To explore the experiences of people with post-stroke aphasia in relation to participating in group-based rehabilitation programmes organized by community-based organizations.

METHODS & PROCEDURES

A qualitative design was adopted, including individual, semi-structured interviews with 20 adults with post-stroke aphasia recruited from community-based rehabilitation centres and support groups. The participants had a mean age of 68.86 ± 13.54 years and a mean post-stroke duration of 9.24 ± 7.72 years. They had participated in at least one group-based rehabilitation programme organized by community-based organizations in the past year. The participants were asked about their experiences of attending group-based programme(s), thoughts and feelings while interacting with the facilitators and group members, and satisfaction with their participation. The interview data were thematically analysed.

OUTCOMES & RESULTS

Three themes were identified: (1) hurdles to active and fulfilling participation including the dominance of verbal sharing, short duration of the programme, being a minority in the group and accumulated negative experiences; (2) strategies adopted to improve participation including accepting a reduced speaking ability, having support from caregivers, and trying mobile apps to vocalize and supplement meanings; and (3) a preference for certain group conditions including receiving invitations by staff with whom they were familiar, groups that are led by experienced facilitators, a large or small group, the dominance of non-verbal activities, and inclusion of only people with post-stroke aphasia.

CONCLUSIONS & IMPLICATIONS

The findings showed that people with post-stroke aphasia experience difficulties participating more actively in group-based rehabilitation programmes due to hurdles in terms of the structure and format of the programmes and accumulation of negative experiences. Facilitating positive group experiences for these people with innovative methods, such as using technology and providing professional and standby support, would be helpful. Longer sessions with smaller groups, exclusively including people with post-stroke aphasia and involving more non-verbal activities to help them express feelings, are suggested to optimize the benefits they derive from these group-based programmes.

WHAT THIS PAPER ADDS

What is already known on the subject Stroke-specific or general group-based rehabilitation programmes are commonly offered by community-based organizations to support the recovery of people with or without stroke. However, some people with post-stroke aphasia may be unable to participate fully in verbal sharing of experiences and exchange of thoughts during these group-based programmes, which can limit the benefits they derive from these programmes. What this paper adds to existing knowledge This study explored the experiences of people with post-stroke aphasia in relation to participating in group-based rehabilitation programmes not specifically designed for people with stroke-induced aphasia organized by community-based organizations. The findings provide an insight into how these people participate in groups, their thoughts and feelings during interactions with the facilitators and group members, their satisfaction with their level of participation, and the characteristics of the groups they prefer to join. What are the potential or actual clinical implications of this work? People with post-stroke aphasia experience difficulties participating more actively in group-based programmes due to hurdles in terms of the structure and format of the group-based programmes and accumulation of negative experiences contributing to decreased motivation to participating in groups. More positive group experiences can be fostered by adopting longer sessions with smaller groups that exclusively include people with post-stroke aphasia and involve more non-verbal activities to help them express their feelings. Communication partner training for facilitators and the use of technology to support communication are suggested to promote active and fulfilling participation of the people with aphasia in group-based programmes.

Targeted neurorehabilitation strategies in post-stroke aphasia

BACKGROUND

Aphasia is a debilitating language impairment, affecting millions of people worldwide. About 40% of stroke survivors develop chronic aphasia, resulting in life-long disability.

OBJECTIVE

This review examines extrinsic and intrinsic neuromodulation techniques, aimed at enhancing the effects of speech and language therapies in stroke survivors with aphasia.

METHODS

We discuss the available evidence supporting the use of transcranial direct current stimulation (tDCS), repetitive transcranial magnetic stimulation, and functional MRI (fMRI) real-time neurofeedback in aphasia rehabilitation.

RESULTS

This review systematically evaluates studies focusing on efficacy and implementation of specialized methods for post-treatment outcome optimization and transfer to functional skills. It considers stimulation target determination and various targeting approaches. The translation of neuromodulation interventions to clinical practice is explored, emphasizing generalization and functional communication. The review also covers real-time fMRI neurofeedback, discussing current evidence for efficacy and essential implementation parameters. Finally, we address future directions for neuromodulation research in aphasia.

CONCLUSIONS

This comprehensive review aims to serve as a resource for a broad audience of researchers and clinicians interested in incorporating neuromodulation for advancing aphasia care.

Efficacy of a multicomponent singing intervention on communication and psychosocial functioning in chronic aphasia: a randomized controlled crossover trial

The ability to produce words through singing can be preserved in severe aphasia, but the benefits of group-based singing rehabilitation in aphasia are largely unknown. Our aim was to determine the efficacy of a multicomponent singing intervention on communication and speech production, emotional-social functioning and caregiver well-being in aphasia. Fifty-four patients with acquired brain injury and chronic aphasia and their family caregivers (n = 43) were recruited. Using a crossover randomized controlled trial design, participants were randomized to two groups who received a 4-month singing intervention either during the first or second half of the study in addition to standard care. The intervention comprised weekly group-based training (including choir singing and group-level melodic intonation therapy) and tablet-assisted singing training at home. At baseline, 5- and 9-month stages, patients were assessed with tests and questionnaires on communication and speech production, mood, social functioning, and quality of life and family caregivers with questionnaires on caregiver burden. All participants who participated in the baseline measurement (n = 50) were included in linear mixed model analyses. Compared with standard care, the singing intervention improved everyday communication and responsive speech production from baseline to 5-month stage, and these changes were sustained also longitudinally (baseline to 9-month stage). Additionally, the intervention enhanced patients' social participation and reduced caregiver burden. This study provides novel evidence that group-based multicomponent singing training can enhance communication and spoken language production in chronic aphasia as well as improve psychosocial wellbeing in patients and caregivers. https://www.clinicaltrials.gov, Unique identifier: NCT03501797.

A systematic review of maintenance following intensive therapy programs in chronic post-stroke aphasia: importance of individual response analysis

PURPOSE

Recent evidence supports the benefit of intensive aphasia intervention programs for people with chronic aphasia, yet it is unclear if all participants can expect positive outcomes and for how long therapeutic gains last.

METHODS

We systematically searched for studies investigating intensive interventions in chronic aphasia. To explore individual response rates and maintenance of therapeutic gains we carried out meta-synthesis by calculating and analysing the Standard Error of Measurement and Minimal Detectable Change metrics of six common outcome measures.

RESULTS

Forty-four studies comprising 24 experimental (13 group, 11 single-subject) and 20 non-experimental studies met our inclusion criteria (n = 670). Whereas most group studies reported statistically significant post-therapy improvement and maintenance, analysis of individual participant data (IPD, n = 393) from these studies revealed that only about a third of participants were classified as "immediate responders," of which more than a third had lost their initial immediate gains at follow-up. This pattern did not change when IPD from single-subject studies (n = 49) was added to the analysis. Thus, only 22% of all IPD receiving an intensive intervention improved significantly and maintained their therapy gains.

CONCLUSIONS

Intensive aphasia therapy is effective when measured at the group-level, but many individuals do not respond significantly to the intervention, and even fewer individuals preserve their initial gains. Group study results do not allow prediction of an individual's response to the intervention. Future research should elucidate which factors mediate positive treatment response and maintenance for an individual.Implications for rehabilitationOnly a small proportion (about one fifth in this review) of intensive aphasia treatment program participants respond and maintain their therapy gains, a fact that is obscured by traditional p-value group analysis.A simple clinical decision-making method is presented for evaluating individual therapy gains and their maintenance.For some immediate treatment responders (about one third in this review), gains from intensive therapy programs are unlikely to be maintained in the long-term without additional, ongoing practice.Clinicians should consider the possibility of individual clients losing some of their therapy gains and take proactive steps to support long-term maintenance.

The efficacy of a directed rhythmic-melodic voice training in the treatment of chronic non-fluent aphasia-Behavioral and imaging results

The main objective of this study was to investigate the efficacy of a directed rhythmic-melodic voice training (SIPARI) compared to language therapy with the focus on improvement in expressive linguistic performance. 20 patients suffering from chronic non-fluent aphasia, allocated by coin tossing to either of the groups, participated in 32 single therapy sessions over a period of 4 months. Before and after therapy, independent testers performed a standardized language test (Aachener Aphasie Test). Behavioral assessments revealed that improvements of patients of the experimental group were clinically significant compared to those of the control group. These improvements concerned the description level articulation and prosody for spontaneous speech and the subtests repetition, naming, and comprehension. Based on these improvements, a significant increase in profile level (effect size (ES) = 2.028, p < 0.001) was assessed, an overall and clinically relevant measure of the severity of aphasia. Additional fMRI examinations yielded activation in the left superior frontal gyrus for the post-minus pre- therapy assessments only for participants of the experimental group. Since this brain region is reported to be particularly involved in executive processing, we assume that the directed procedure of the SIPARI treatment with regard to musical, linguistic, and cognitive function potentially holds the key for successful language rehabilitation. While our imaging results hint at a possible explanation for its efficacy, our behavioral results corroborate the efficacy of this therapy in the treatment of chronic non-fluent aphasia patients. DRKS00026730, 19.10.21, retrospectively registered https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00026730.

Noninvasive brain stimulation to augment language therapy for poststroke aphasia

Behavioral language treatment approaches represent the standard of care for persons with aphasia (PWA), but the benefits of these treatments are variable. Moreover, due to the logistic and financial limitations on the amount of behavioral therapy available to patients, it is often infeasible for PWA to receive behavioral interventions with the level of frequency, intensity, or duration that would provide significant and lasting benefit, underscoring the need for novel, effective treatment approaches. Noninvasive brain stimulation (NIBS) techniques, such as transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), have emerged as promising neurally-based tools to enhance language abilities for PWA following stroke. This chapter first provides an overview of the methods and physiologic basis motivating the use of NIBS to enhance aphasia recovery followed by a selective review of the growing evidence of its potential as a novel therapeutic tool. Subsequent sections discuss some of the principles that may prove most useful in guiding and optimizing the effects of NIBS on aphasia recovery, focusing on how the functional state of the brain at the time of stimulation interacts with the behavioral aftereffects of neuromodulation. We conclude with a discussion of current challenges and future directions for NIBS in aphasia treatment.

Auditory Comprehension Deficits in Post-stroke Aphasia: Neurologic and Demographic Correlates of Outcome and Recovery

Introduction: One of the most challenging symptoms of aphasia is an impairment in auditory comprehension. The inability to understand others has a direct impact on a person's quality of life and ability to benefit from treatment. Despite its importance, limited research has examined the recovery pattern of auditory comprehension and instead has focused on aphasia recovery more generally. Thus, little is known about the time frame for auditory comprehension recovery following stroke, and whether specific neurologic and demographic variables contribute to recovery and outcome.

Methods: This study included 168 left hemisphere chronic stroke patients stroke patients with auditory comprehension impairments ranging from mild to severe. Univariate and multivariate lesion-symptom mapping (LSM) was used to identify brain regions associated with auditory comprehension outcomes on three different tasks: Single-word comprehension, yes/no sentence comprehension, and comprehension of sequential commands. Demographic variables (age, gender, and education) were also examined for their role in these outcomes. In a subset of patients who completed language testing at two or more time points, we also analyzed the trajectory of recovery in auditory comprehension using survival curve-based time compression.

Results: LSM analyses revealed that poor single-word auditory comprehension was associated with lesions involving the left mid- to posterior middle temporal gyrus, and portions of the angular and inferior-middle occipital gyri. Poor yes/no sentence comprehension was associated almost exclusively with the left mid-posterior middle temporal gyrus. Poor comprehension of sequential commands was associated with lesions in the left posterior middle temporal gyrus. There was a small region of convergence between the three comprehension tasks, in the very posterior portion of the left middle temporal gyrus. The recovery analysis revealed that auditory comprehension scores continued to improve beyond the first year post-stroke. Higher education was associated with better outcome on all auditory comprehension tasks. Age and gender were not associated with outcome or recovery slopes.

Conclusions: The current findings suggest a critical role for the posterior left middle temporal gyrus in the recovery of auditory comprehension following stroke, and that spontaneous recovery of auditory comprehension can continue well beyond the first year post-stroke.

Factors predicting long-term recovery from post-stroke aphasia

BACKGROUND

It remains widely accepted that spontaneous recovery from aphasia is largely limited to the first related factors. This has direct implications for acute and chronic interventions for aphasia. few months following stroke. A few recent studies challenge this view, revealing that some individuals' language abilities improve even during the chronic stage.

AIMS

To identify prognostic indicators of long-term aphasia recovery.

METHODS & PROCEDURES

Eighteen people with aphasia initially evaluated in the chronic stage were retested at least one year later. The Western Aphasia Battery-Revised (WAB-R) Aphasia Quotient (AQ) was used to quantify changes in language impairment. Prognostic factors included those related to the patient (demographic, psychosocial), stroke (lesion volume and location), and treatment (medical, rehabilitative).

OUTCOMES & RESULTS

Twelve participants improved and 6 remained stable or declined. Linear regression analysis revealed that lesion volume predicted long-term language gains, with smaller lesions yielding greater improvements. Individuals who did not improve were more likely to have lesions encompassing critical frontal and temporoparietal cortical regions and interconnecting white matter pathways. Exploratory regression analysis of psychosocial and treatment-related factors revealed a positive relationship between improvement and satisfaction with life participation, and a negative relationship between improvement and perceived impairment severity. Critically, psychosocial and treatment-related factors significantly improved model fit over lesion volume, suggesting that these factors add predictive value to determining long-term aphasia prognosis.

CONCLUSIONS

Long-term aphasia recovery is multidetermined by a combination of stroke-, psychosocial-, and treatment-related factors. This has direct implications for acute and chronic interventions for aphasia.

Individualized response to semantic versus phonological aphasia therapies in stroke

Attempts to personalize aphasia treatment to the extent where it is possible to reliably predict individual response to a particular treatment have yielded inconclusive results. The current study aimed to (i) compare the effects of phonologically versus semantically focussed naming treatment and (ii) examine biographical and neuropsychological baseline factors predictive of response to each treatment. One hundred and four individuals with chronic post-stroke aphasia underwent 3 weeks of phonologically focussed treatment and 3 weeks of semantically focussed treatment in an unblinded cross-over design. A linear mixed-effects model was used to compare the effects of treatment type on proportional change in correct naming across groups. Correlational analysis and stepwise regression models were used to examine biographical and neuropsychological predictors of response to phonological and semantic treatment across all participants. Last, chi-square tests were used to explore the association between treatment response and phonological and semantic deficit profiles. Semantically focussed treatment was found to be more effective at the group-level, independently of treatment order (P = 0.041). Overall, milder speech and language impairment predicted good response to semantic treatment (r range: 0.256-0.373) across neuropsychological tasks. The Western Aphasia Battery-Revised Spontaneous Speech score emerged as the strongest predictor of semantic treatment response (R 2 = 0.188). Severity of stroke symptoms emerged as the strongest predictor of phonological treatment response (R 2 = 0.103). Participants who showed a good response to semantic treatment were more likely to present with fluent speech compared to poor responders (P = 0.005), whereas participants who showed a good response to phonological treatment were more likely to present with apraxia of speech (P = 0.020). These results suggest that semantic treatment may be more beneficial to the improvement of naming performance in aphasia than phonological treatment, at the group-level. In terms of personalized predictors, participants with relatively mild impairments and fluent speech responded better to semantic treatment, while phonological treatment benefitted participants with more severe impairments and apraxia of speech.

Intermittent Theta Burst Stimulation (iTBS) for Treatment of Chronic Post-Stroke Aphasia: Results of a Pilot Randomized, Double-Blind, Sham-Controlled Trial

Background

Research indicates intermittent theta burst stimulation (iTBS) is a potential treatment of post-stroke aphasia.

Material/Methods

In this double-blind, sham-controlled trial (NCT 01512264) participants were randomized to receive 3 weeks of sham (G₀), 1 week of iTBS/2 weeks of sham (G₁), 2 weeks of iTBS/1 week of sham (G₂), or 3 weeks of iTBS (G₃). FMRI localized residual language function in the left hemisphere; iTBS was applied to the maximum fMRI activation in the residual language cortex in the left frontal lobe. FMRI and aphasia testing were conducted pre-treatment, at ≤1 week after completing treatment, and at 3 months follow-up.

Results

27/36 participants completed the trial. We compared G₀ to each of the individual treatment group and to all iTBS treatment groups combined (G_1–3). In individual groups, participants gained (of moderate or large effect sizes; some significant at P<0.05) on the Boston Naming Test (BNT), the Semantic Fluency Test (SFT), and the Aphasia Quotient of the Western Aphasia Battery-Revised (WAB-R AQ). In G_1–3, BNT, and SFT improved immediately after treatment, while the WAB-R AQ improved at 3 months. Compared to G₀, the other groups showed greater fMRI activation in both hemispheres and non-significant increases in language lateralization to the left hemisphere. Changes in IFG connectivity were noted with iTBS, showing differences between time-points, with some of them correlating with the behavioral measures.

Conclusions

The results of this pilot trial support the hypothesis that iTBS applied to the ipsilesional hemisphere can improve aphasia and result in cortical plasticity.

Treatment of post-stroke aphasia: A narrative review for stroke neurologists

This review is intended to help physicians guide patients to optimal management of post-stroke aphasia. We review literature on post-stroke aphasia treatment, focusing on: (1) when and for whom language therapy is most effective, (2) the variety of approaches that can be effective for different individuals, and (3) the extent to which behavioral therapy might be augmented by non-invasive brain stimulation and/or medications.

Current Approaches to the Treatment of Post-Stroke Aphasia

Aphasia, impairment of language after stroke or other neurological insult, is a common and often devastating condition that affects nearly every social activity and interaction. Behavioral speech and language therapy is the mainstay of treatment, although other interventions have been introduced to augment the effects of the behavioral therapy. In this narrative review, we discuss advances in aphasia therapy in the last 5 years and focus primarily on properly powered, randomized, controlled trials of both behavioral therapies and interventions to augment therapy for post-stroke aphasia. These trials include evaluation of behavioral therapies and computer-delivered language therapies. We also discuss outcome prediction trials as well as interventional trials that have employed noninvasive brain stimulation, or medications to augment language therapy. Supported by evidence from Phase III trials and large meta-analyses, it is now generally accepted that aphasia therapy can improve language processing for many patients. Not all patients respond similarly to aphasia therapy with the most severe patients being the least likely responders. Nevertheless, it is imperative that all patients, regardless of severity, receive aphasia management focused on direct therapy of language deficits, counseling, or both. Emerging evidence from Phase II trials suggests transcranial brain stimulation is a promising method to boost aphasia therapy outcomes.

Methodological Considerations for Incorporating Clinical Data Into a Network Model of Retrieval Failures

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.

Prediction of Aphasia Severity in Patients with Stroke Using Diffusion Tensor Imaging

This study classified the severity of aphasia through the Western Aphasia Battery and determined the optimal cut-off value for each Language-Related White Matter fiber and their combinations, we further examined the correlations between Language-Related White Matter and Western Aphasia Battery subscores. This retrospective study recruited 64 patients with aphasia. Mild/moderate and severe aphasia were classified according to cut-off Aphasia Quotient score of 51 points. Diffusion tensor imaging and fractional anisotropy reconstructed Language-Related White Matter in multiple fasciculi. We determined the area under the covariate-adjusted receiver operating characteristic curve to evaluate the accuracy of predicting aphasia severity. The optimal fractional-anisotropy cut-off values for the individual fibers of the Language-Related White Matter and their combinations were determined. Their correlations with Western Aphasia Battery subscores were analyzed. The arcuate and superior longitudinal fasciculi showed fair accuracy, the inferior frontal occipital fasciculus poor accuracy, and their combinations fair accuracy. Correlations between Language-Related White Matter parameters and Western Aphasia Battery subscores were found between the arcuate, superior longitudinal, and inferior frontal occipital fasciculi and spontaneous speech, auditory verbal comprehension, repetition, and naming. Diffusion-tensor-imaging-based language-Related White Matter analysis may help predict the severity of language impairment in patients with aphasia following stroke.

5-year course of therapy-induced recovery in chronic non-fluent aphasia - Three single cases

Over a period of five years, three severely impaired chronic non-fluent aphasia patients with concomitant apraxia of speech (AOS) received annual treatment periods of specific rhythmic-melodic voice training SIPARI. This therapy concept focusses on improving planning, programming, and sequencing of speech movements emphasizing specifically the training of cognitive capabilities such as executive functions. Behavioral and neural data were assessed at the start of the therapy and continuously after each treatment period. As previously reported, a first major finding was that after the first treatment period, significant improvements in language and speech motor performance were measured going hand in hand with significant additional peri-lesional activation in all patients particularly in the posterior part of the left superior temporal gyrus. This activation pattern was continuously confirmed by each subsequent scan. However, assessments after the third treatment period yielded additional significant activations in dorsolateral prefrontal cortex regions, namely in the left middle and superior frontal gyri, and anterior cingulate gyrus resulting in a further statistically significant increase in speech profile level, an overall and clinically relevant measure of the severity of aphasia. On the basis of our results, we assume that even in long-term rehabilitation of severely impaired non-fluent aphasia patients the applied treatment may support coactivation with dorsolateral prefrontal regions, suggested to be particularly involved in cognitive processing. This left-lateralized dorsolateral prefrontal-parietal network is supposed to be engaged in domain-general aspects of active phonological memory. To the best of our knowledge, no comparable studies are available as yet. Therefore, we hope that our study may serve to attract more attention for the late stages of long-term rehabilitation, not at least as a challenge for therapists and researchers alike.

Do caregivers' personality and emotional intelligence modify their perception of relationship and communication with people with aphasia?

BACKGROUND

There is a wide agreement that family and friends of people with aphasia (PWA) can play a crucial role in the rehabilitation of interpersonal communication. Therefore, speech and language therapists (SLTs) should include family and friends in the process of therapy. However, little has been said about the role of caregivers of severely disabled PWA in the rehabilitation of communication functions.

AIMS

To examine how caregivers of severely disabled PWA perceive their relationship and communication with PWA, how they facilitate communication with PWA, and whether the caregiver's personality and emotional intelligence modify the abovementioned processes.

METHODS & PROCEDURES

The study involved 123 caregivers of severely disabled stroke survivors with aphasia. Participants took part in a structured interview based on a structured interview guide created for the purpose of this study. The standardized psychological questionnaires NEO Five-Factor Inventory (NEO-FFI) and Schutte Emotional Intelligence Scale (SEIS) were used.

OUTCOMES & RESULTS

The caregiver's positive attitude towards the PWA correlated with the active facilitation of communication. The personality traits of caregivers and their level of emotional intelligence were associated with the tendency to use certain techniques to facilitate communication with PWA.

CONCLUSIONS & IMPLICATIONS

Caregivers' positive attitude towards PWA is beneficial for the rehabilitation of communicative functions. Personality traits and emotional intelligence could modify the caregiver's strategy of coping with aphasia-related challenges and should be taken into consideration when providing support. What this paper adds What is already known on the subject Interpersonal communication must by definition involve at least two people. Therefore, there are a lot of approaches in SLT where support is given not only to the PWA but also to the communication partners. The most important group is significant others, which is usually understood as family members and friends. There is an increasing recognition that SLTs should include them in therapy. What this paper adds to existing knowledge For those PWA who need constant care, caregivers may have a significant influence on the quality of communication. Their positive attitude towards PWA corresponds with more active facilitation of communication and can make rehabilitation more efficacious. Caregivers should be educated on the cognitive and behavioural aspects of aphasia and encouraged to look actively for a PWA's positive characteristics. Caregivers' personality traits play a role in facilitating communication. For example, caregivers with high agreeableness are more likely to enjoy providing care, while those with higher conscientiousness declare using more techniques to facilitate communication with the PWA. What are the potential or actual clinical implications of this work? Caregivers' personality traits play a role in caring. Their positive attitude towards PWA corresponds to more active facilitation of communication, which can lead to more effective rehabilitation. This should be taken into account when training caregivers. Training programmes should include cognitive and behavioural aspects of aphasia as well as emphasize the need to maximize the PWA's abilities.

Telepractice for Adult Speech-Language Pathology Services: A Systematic Review

Purpose

We conducted a systematic review of the literature regarding adult telepractice services (screening, assessment, and treatment) from approximately 2014 to 2019.

Method

Thirty-one relevant studies were identified from a literature search, assessed for quality, and reported.

Results

Included studies illustrated feasibility, efficacy, diagnostic accuracy, and noninferiority of various speech-language pathology services across adult populations, including chronic aphasia, Parkinson's disease, dysphagia, and primary progressive aphasia. Technical aspects of the equipment and software used to deliver services were discussed. Some general themes were noted as areas for future research.

Conclusion

Overall, results of the review continue to support the use of telepractice as an appropriate service delivery model in speech-language pathology for adults. Strong research designs, including experimental control, across multiple well-described settings are still needed to definitively determine effectiveness of telepractice services.

Leukoaraiosis Is Associated With a Decline in Language Abilities in Chronic Aphasia

Background. A fraction of stroke survivors with chronic aphasia experience declines in language abilities over time, but the reason for this remains unclear. Objective. To evaluate the effect of leukoaraiosis on baseline aphasia severity and long-term changes in aphasia severity. This study directly compares the predictive capacity of leukoaraiosis severity to that of lesion damage, a factor known to account for a substantial proportion of variance in the degree of language impairment and recovery. Methods. Using a longitudinal database of behavioral and neuroimaging data from 35 individuals in the chronic stage of recovery after a single-event left-hemisphere stroke (9 females, mean stroke age = 55.8 ± 9.1 years, mean months poststroke at initial evaluation = 36.3 ± 40.8), we examined 2 lines of inquiry: (1) to what extent does leukoaraiosis severity at initial evaluation predict aphasia severity and (2) to what extent does leukoaraiosis severity at initial evaluation predict longitudinal change in aphasia severity. Participants underwent high-resolution magnetic resonance imaging for the purpose of lesion volume analysis and leukoaraiosis severity rating. Biographical information was also considered. Results. Lesion volume and time poststroke at initial assessment best predicted initial aphasia severity (adjusted R2 = 0.37). Leukoaraiosis severity and initial aphasia severity significantly predicted decline in language abilities at follow-up, accounting for approximately one-third of the variance (adjusted R2 = 0.33). More severe leukoaraiosis was associated with a 4.3 odds increase of decline. Conclusions. Leukoaraiosis is a significant risk factor for declining language abilities in aphasia and should be considered for better identification of individuals at risk for long-term decline, which can guide clinical decision making.