Mechanisms underlying anomia treatment outcomes

Combining executive function training and anomia therapy in chronic post-stroke aphasia: A preliminary study of multidimensional effects

PURPOSE

The influential relationship between executive functioning and aphasia rehabilitation outcomes has been addressed in a number of studies, but few have studied the effect of adding executive function training to linguistic therapies. The present study aimed to measure the effects of combining, within therapy sessions, executive function training and anomia therapy on naming and discourse abilities in people with chronic aphasia.

METHOD

A single-case experimental design with multiple baselines across participants was used. Four persons with chronic post-stroke aphasia received 12 sessions of a tailored treatment combining executive function training and semantic feature analysis (SFA) therapy. Naming accuracy of treated items was examined over the course of the treatment while control naming scores of untreated items and discourse measures were collected pre-treatment, immediately post-treatment, and 4 weeks post-treatment, in order to investigate the multidimensional effects of the treatment and their maintenance.

RESULT

Naming skills improved in all participants for treated and untreated items, were maintained over time, and were accompanied by improved discourse abilities. Visual and statistical analyses showed a significant treatment effect for naming skills in three out of the four participants.

CONCLUSION

A combination of executive function training and SFA treatment in people with chronic aphasia may improve both naming skills and discourse efficiency. Further studies are needed to substantiate these promising preliminary results.

A systematic review of Phonological Components Analysis therapy studies for aphasia

Among the wide range of anomia treatments for persons with aphasia (PWA), Phonological Components Analysis (PCA) is a well-known alternative. A systematic review of PCA efficacy studies for PWA was conducted to extract treatment-related and participant-related characteristics, to synthesise immediate and long-term outcomes and to assess the methodological quality of PCA studies (PROSPERO pre-registration CRD42024552047). Experimental studies on adults with post-stroke aphasia focusing on the efficacy of PCA published in English were included. Studies combining PCA with other treatment approaches, involving people with neurodegenerative disorders, without efficacy measures, or in dissertations, theses, and conference papers were excluded. The EBSCOhost platform and citations of the original PCA paper were last searched in November 2024. In total, thirteen studies were selected involving 89 PWA. Participants were at least 6 months post-stroke, and 75 % of them presented with Broca's or anomic aphasia. The quality of PCA efficacy studies was relatively high according to the Single Case Experimental Design scale (mean 8.6 ± 1.0, range 7-10). Picture naming improved to reach at least a small effect size in 74 % of PWA (58/85) for trained items immediately after PCA and in 55 % of PWA (38/71) in the maintenance phase. Generalisation to untrained items occurred in 37 % of participants (22/59). Overall, PCA led to positive outcomes in the majority of PWA, which were often item-specific. As experimental designs were highly heterogeneous, further research is needed to better understand the optimal target population for PCA, the ideal dosage distribution, the key ingredients driving the improvement, and their neural correlates.

Effectiveness of French Phonological Components Analysis in individuals with chronic aphasia

BACKGROUND

Over 50% of individuals with aphasia face ongoing word-finding issues. Studies have found phonologically oriented therapy helpful for English speakers, but this has not yet been studied in French. It is essential to assess the effectiveness of such a therapy in French, considering the distinct linguistic typologies between both languages, which may impact the outcomes of phonologically oriented interventions.

AIM

This paper evaluates the effectiveness of French Phonological Component Analysis (Fr-PCA) on communication skills of individuals with chronic aphasia and the impact of individual factors on treatment success.

METHODS & PROCEDURES

Eighteen individuals with chronic aphasia received 15 h of Fr-PCA therapy over 5 weeks. Naming accuracy for treated and untreated words was measured before and after therapy, as well as at 3- and 6-month follow-ups. Secondary outcome measures included standardized tests measuring within-level generalization (object and action naming) and across-level generalization (repetition, verbal fluency, oral comprehension, communication effectiveness reported by a frequent communication partner).

OUTCOMES & RESULTS

Fr-PCA led to improved accuracy for treated (17 participants out of 18) and untreated words (9 participants out of 18), with gains maintained at 6-month follow-up (7 participants out of 10 for treated and 6 participants out of 10 for untreated), and generalization to communication effectiveness reported by a frequent communication partner (11 participants out of 16). Age, apraxia of speech severity and initial anomia severity impacted therapy gains.

CONCLUSIONS & IMPLICATIONS

Though more research is needed, results suggest Fr-PCA benefits French individuals living with aphasia. Identifying individual factors influencing therapy gains could enable clinicians to improve therapy tailoring.

WHAT THIS PAPER ADDS

What is already known on this subject Phonological Component Analysis (PCA) improves naming of treated and untreated items in individuals living with aphasia. There is also evidence supporting long-lasting benefits following PCA. However, PCA has never been studied in French, a language presenting with a different linguistic typology than English, and we know little as to which individual factors can influence PCA therapy benefits. What this paper adds to existing knowledge Through group-level analyses on both personalized sets and standardized tests, this study shows that PCA constitutes an effective therapy protocol for francophone individuals living with aphasia. The gains are measured on treated and untreated items and generalized to levels other than naming, such as communication effectiveness. Individual factors such as age, initial anomia severity and apraxia of speech severity influence therapy outcomes. What are the potential or actual clinical implications of this work? There is now evidence supporting PCA in French, a language with strong morphological-phonological interactions. Furthermore, when working with individuals living with aphasia and severe anomia or apraxia of speech, gains can still be made, but might be longer to attain.

Determinants of Multilevel Discourse Outcomes in Anomia Treatment for Aphasia

PURPOSE

Individuals with aphasia identify discourse-level communication (i.e., language in use) as a high priority for treatment. The central premise of most aphasia treatments is that restoring language at the phoneme, word, and/or sentence level will generalize to discourse. However, treatment-related changes in discourse-level communication are modest, are poorly understood, and vary greatly among individuals with aphasia. In response, this study consisted of a multilevel discourse analysis of archival, monologic discourse outcomes across two high-intensity Semantic Feature Analysis (SFA) clinical trials. Aim 1 evaluated changes in theoretically motivated discourse outcomes representing lexical-semantic processing, lexical diversity, grammatical complexity, and discourse informativeness. Aim 2 explored the potential moderating role of nonlanguage cognitive factors (semantic memory, divided attention, and executive function) on discourse outcomes.

METHOD

This study was a retrospective analysis of archival monologic discourse outcomes after intensive SFA for n = 60 (Aim 1) and a subset n = 44 (Aim 2). Outcome measures included lexical-semantic processing (% semantic errors), lexical diversity (moving average type-token ratio), grammatical complexity (mean utterance length), and discourse informativeness (% correct information units). Bayesian generalized mixed-effects models were used to examine changes across four study time points: enrollment, entry, exit, and 1-month follow-up.

RESULTS

The present study found no evidence for meaningful or statistically reliable improvements in monologue discourse performance after SFA when measured using standard, general-topic discourse stimuli. There was weak and inconsistent evidence that nonlanguage cognitive factors may play a role in moderating treatment response.

CONCLUSIONS

These findings indicate a clear need to pair theoretically informed treatments designed to facilitate generalization to discourse with intentional measurement paradigms designed to capture it. Furthermore, there is a clear need to examine how established treatments, restorative or compensatory, can better facilitate generalization to discourse-level communication. These priorities are critical for meaningfully improving everyday communication and reducing the profound communication and psychosocial consequences of aphasia.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.26524081.

Assessing Relative Linguistic Impairment With Model-Based Item Selection

PURPOSE

A picture naming test is presented that reveals impairment to specific mechanisms involved in the naming process, using accuracy scores on curated item sets. A series of psychometric validation experiments are reported.

METHOD

Using a computational model that enables estimation of item difficulty at the lexical and sublexical stages of word retrieval, two complimentary sets of items were constructed that challenge the respective psycholinguistic levels of representation. The difference in accuracy between these item sets yields the relative linguistic impairment (RLI) score. In a cohort of 91 people with chronic left-hemisphere stroke who enrolled in a clinical trial for anomia, we assessed psychometric properties of the RLI score and then used the new scale to make predictions about other language behaviors, lesion distributions, and functional activation during naming.

RESULTS

RLI scores had adequate psychometric properties for clinical significance. RLI scores contained predictive information about spontaneous speech fluency, over and above accuracy. A dissociation was observed between performance on the RLI item sets and performance on the subtests of an independent language battery. Sublexical RLI was significantly associated with apraxia of speech and with lesions encompassing perisylvian regions, while lexical RLI was associated with lesions to deep white matter. The RLI construct was reflected in functional brain activity during naming, independent of overall accuracy, with a respective shift of activation between dorsal and ventral networks responsible for different aspects of word retrieval.

CONCLUSION

The RLI assessment satisfies the psychometric requirements to serve as a useful clinical measure.

A Meta-Analysis of Anomia Treatment in Bilingual Aphasia: Within- and Cross-Language Generalization and Predictors of the Treatment Outcomes

PURPOSE

The present meta-analysis investigated the efficacy of anomia treatment in bilingual and multilingual persons with aphasia (BPWAs) by assessing the magnitudes of six anomia treatment outcomes. Three of the treatment outcomes pertained to the "trained language": improvement of trained words (treatment effect [TE]), within-language generalization of semantically related untrained words (WLG-Related), and within-language generalization of unrelated words (WLG-Unrelated). Three treatment outcomes were for the "untrained language": improvement of translations of the trained words (cross-language generalization of trained words [CLG-Tx]), cross-language generalization of semantically related untrained words (CLG-Related), and cross-language generalization of unrelated untrained words (CLG-Unrelated). This study also examined participant- and treatment-related predictors of these treatment outcomes.

METHOD

This study is registered in the International Prospective Register of Systematic Reviews (PROSPERO) under the number CRD42023418147. Nine electronic databases were searched to identify word retrieval treatment studies of poststroke BPWAs of at least 6 months postonset. Pre- and posttreatment single-word naming scores were extracted for each eligible participant and used to calculate effect sizes (within-case Cohen's d) of the six treatment outcomes. Random-effects meta-analyses were conducted to assess weighted mean effect sizes of the treatment outcomes across studies. Multiple linear regression analyses were used to examine the effects of participant-related variables (pretreatment single-word naming and comprehension representing poststroke lexical processing abilities) and treatment-related variables (type, language, and duration). The methodological quality of eligible studies and the risk of bias in this meta-analysis were assessed.

RESULTS

A total of 17 published studies with 39 BPWAs were included in the meta-analysis. The methodological quality of the included studies ranged from fair (n = 4) to good (n = 13). Anomia treatment produced a medium effect size for TE (M = 8.36) and marginally small effect sizes for WLG-Related (M = 1.63), WLG-Unrelated (M = 0.68), and CLG-Tx (M = 1.56). Effect sizes were nonsignificant for CLG-Related and CLG-Unrelated. TE was significantly larger than the other five types of treatment outcomes. TE and WLG-Related effect sizes were larger for BPWAs with milder comprehension or naming impairments and for treatments of longer duration. WLG-Unrelated was larger when BPWAs received phonological treatment than semantic and mixed treatments. The overall risk of bias in the meta-analysis was low with a potential risk of bias present in the study identification process.

CONCLUSIONS

Current anomia treatment practices for bilingual speakers are efficacious in improving trained items but produce marginally small within-language generalization and cross-language generalization to translations of the trained items. These results highlight the need to provide treatment in each language of BPWAs and/or investigate other approaches to promote cross-language generalization. Furthermore, anomia treatment outcomes are influenced by BPWAs' poststroke single-word naming and comprehension abilities as well as treatment duration and the provision of phonological treatment.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.25595712.

Focusing on the locus of the breakdown for treatment of anomia: a pilot study

The primary goal of this study was to evaluate the treatment effects of semantic feature analysis (SFA) and phonological components analysis (PCA) on word retrieval processing in persons with aphasia (PWAs). After identifying the locus of the breakdown in lexical retrieval processing, 15 monolingual native Persian speakers with aphasia were divided into two groups. After three naming trials, participants with dominant semantic deficits received SFA, and participants with primary phonological deficits were provided with PCA three times a week for eight weeks. Both approaches improved participants' naming and performance on language tests, including spontaneous speech, repetition, comprehension, and semantic processing. However, the correct naming of treated and untreated items was higher in mild-to-moderate participants, with mostly circumlocution and semantic paraphasias in the SFA group. The same holds for mild-to-moderate participants with mostly phonemic paraphasia who received PCA therapy. Moreover, the results showed that participants' baseline naming performance and semantic abilities could be associated with the treatment outcomes. Although limited by a lack of a control group, this study provided evidence supporting the possible benefits of focusing on the locus of the breakdown for treating anomia through SFA and PCA approaches, specifically in participants with mild to moderate aphasia. However, for those with severe aphasia, the treatment choice may not be as straightforward because several variables are likely to contribute to this population's word-finding difficulties. Replication with larger, well-stratified samples, use of a within-subjects alternating treatment design and consideration of treatments' long-term effects are required to better ascertain the effects of focusing on the locus of breakdown for treatment of anomia.

Early within therapy naming probes as a clinically-feasible predictor of anomia treatment response

This study investigated the relationship between early within-therapy probe naming performance and anomia therapy outcomes in individuals with aphasia. Thirty-four adults with chronic, post-stroke aphasia participated in the Aphasia Language Impairment and Functioning Therapy (Aphasia LIFT) programme, comprised of 48 h of comprehensive aphasia therapy. Sets of 30 treated and 30 untreated items identified at baseline were probed during impairment therapy which targeted word retrieval using a combined semantic feature analysis and phonological component analysis approach. Multiple regression models were computed to determine the relationship between baseline language and demographic variables, early within-therapy probe naming performance (measured after 3 h of impairment therapy) and anomia treatment outcomes. Early within-therapy probe naming performance emerged as the strongest predictor of anomia therapy gains at post-therapy and at 1-month follow-up. These findings have important clinical implications, as they suggest that an individual's performance after a brief period of anomia therapy may predict response to intervention. As such, early within-therapy probe naming may provide a quick and accessible tool for clinicians to identify potential response to anomia treatment.

The Resilience of the Phonological Network May Have Implications for Developmental and Acquired Disorders

A central tenet of network science states that the structure of the network influences processing. In this study of a phonological network of English words we asked: how does damage alter the network structure (Study 1)? How does the damaged structure influence lexical processing (Study 2)? How does the structure of the intact network "protect" processing with a less efficient algorithm (Study 3)? In Study 1, connections in the network were randomly removed to increasingly damage the network. Various measures showed the network remained well-connected (i.e., it is resilient to damage) until ~90% of the connections were removed. In Study 2, computer simulations examined the retrieval of a set of words. The performance of the model was positively correlated with naming accuracy by people with aphasia (PWA) on the Philadelphia Naming Test (PNT) across four types of aphasia. In Study 3, we demonstrated another way to model developmental or acquired disorders by manipulating how efficiently activation spread through the network. We found that the structure of the network "protects" word retrieval despite decreases in processing efficiency; words that are relatively easy to retrieve with efficient transmission of priming remain relatively easy to retrieve with less efficient transmission of priming. Cognitive network science and computer simulations may provide insight to a wide range of speech, language, hearing, and cognitive disorders.

Predictors of Therapy Response in Chronic Aphasia: Building a Foundation for Personalized Aphasia Therapy

Chronic aphasia, a devastating impairment of language, affects up to a third of stroke survivors. Speech and language therapy has consistently been shown to improve language function in prior clinical trials, but few clinicially applicable predictors of individual therapy response have been identified to date. Consequently, clinicians struggle substantially with prognostication in the clinical management of aphasia. A rising prevalence of aphasia, in particular in younger populations, has emphasized the increasing demand for a personalized approach to aphasia therapy, that is, therapy aimed at maximizing language recovery of each individual with reference to evidence-based clinical recommendations. In this narrative review, we discuss the current state of the literature with respect to commonly studied predictors of therapy response in aphasia. In particular, we focus our discussion on biographical, neuropsychological, and neurobiological predictors, and emphasize limitations of the literature, summarize consistent findings, and consider how the research field can better support the development of personalized aphasia therapy. In conclusion, a review of the literature indicates that future research efforts should aim to recruit larger samples of people with aphasia, including by establishing multisite aphasia research centers.

Cognitive Training to Enhance Aphasia Therapy (Co-TrEAT): A Feasibility Study

Persons with aphasia (PWA) often have deficits in cognitive domains such as working memory (WM), which are negatively correlated with recovery, and studies have targeted WM deficits in aphasia therapy. To our knowledge, however, no study has examined the efficacy of multi-modal training which includes both WM training and targeted language therapy. This pilot project examined the feasibility and preliminary efficacy of combining WM training and naming therapy to treat post-stroke PWA. Chronic PWA were randomly assigned to either the a) Phonological Components Analysis (PCA) and WM intervention (WMI) condition (i.e., a computerized adaptive dual n-back task), or b) PCA and active control condition (WMC). Participants received face-to-face PCA therapy 3 times/week for 5 weeks, and simultaneously engaged in WM training or the active control condition five times/week, independently at home. Six PWA were enrolled, 3 in each condition. Feasibility metrics were excellent for protocol compliance, retention rate and lack of adverse events. Recruitment was less successful, with insufficient participants for group analyses. Participants in the WMI (but not the WMC) condition demonstrated a clinically significant (i.e., > 5 points) improvement on the Western Aphasia Battery- Aphasia Quotient (WAB-R AQ) and Boston Naming Test after therapy. Given the small sample size, the performance of two individuals, matched on age, education, naming accuracy pre-treatment, WAB-R AQ and WM abilities was compared. Participant WMI-3 demonstrated a notable increase in WM training performance over the course of therapy; WMC-2 was the matched control. After therapy, WMI-3's naming accuracy for the treated words improved from 30 to 90% (compared to 30–50% for WMC-2) with a 7-point WAB-R AQ increase (compared to 3 for WMC-2). Improvements were also found for WMI-3 but not for WMC-2 on ratings of communicative effectiveness, confidence and some conversation parameters in discourse. This feasibility study demonstrated excellent results for most aspects of Co-TrEAT. Recruitment rate, hampered by limited resources, must be addressed in future trials; remotely delivered aphasia therapy may be a possible solution. Although no firm conclusions can be drawn, the case studies suggest that WM training has the potential to improve language and communication outcomes when combined with aphasia therapy.

Resting-State Functional Connectivity following Phonological Component Analysis: The Combined Action of Phonology and Visual Orthographic Cues

Anomia is the most frequent and pervasive symptom for people with aphasia (PWA). Phonological component analysis (PCA) is a therapy incorporating phonological cues to treat anomia. Investigations of neural correlates supporting improvements following PCA remain scarce. Resting-state functional connectivity (rsFC) as a marker of therapy-induced neuroplasticity has been reported by our team. The present study explores the efficacy of PCA in French and associated therapy-induced neuroplasticity using whole-brain rsFC analysis. Ten PWA participated in a pre-/post-PCA fMRI study with cognitive linguistic assessments. PCA was delivered in French following the standard procedure. PCA led to significant improvement with trained and untrained items. PCA also led to changes in rsFC between distributed ROIs in the semantic network, visual network, and sub-cortical areas. Changes in rsFC can be interpreted within the frame of the visual and phonological nature of PCA. Behavioral and rsFC data changes associated with PCA in French highlight its efficacy and point to the importance of phonological and orthographic cues to consolidate the word-retrieval strategy, contributing to generalization to untrained words.

The effects of intensity on a phonological treatment for anomia in post-stroke aphasia

INTRODUCTION

The evidence regarding optimal treatment intensity is mixed, and differing definitions have further confounded existing findings. The primary objective of this study was to compare the efficacy of Phonological Components Analysis (PCA) treatment for anomia delivered at intense and non-intense schedules, using a well-controlled design. The number of teaching episodes and active ingredients of therapy are important considerations when defining intensity. We hypothesized that an active ingredient of PCA is the self-generation of phonological components during therapy sessions. Our secondary aim was to examine whether component generation predicted treatment outcome.

METHODS

Sixteen adults (M = 52.63 years old, SD = 11.40) with chronic post-stroke aphasia (M = 4.52 years post-onset, SD = 5.55) were randomly assigned to intensive (IT) or standard (ST) PCA treatment conditions. Cumulative treatment intensity in both conditions was equivalent: ST participants received PCA 1 hour/day, 3 days/week for 10 weeks, whereas IT participants received PCA 3 hours/day, 4 days/week for 2.5 weeks. The primary outcome was naming accuracy on a set of treated and (matched) untreated words, measured pre- and post-treatment, and at four- and eight-week follow-ups.

RESULTS

IT and ST conditions were similarly efficacious. However, secondary analyses suggest an advantage for the IT condition in naming of the treated words immediately post-treatment, but not at follow-ups. The self-generation of phonological components emerged as a significant positive predictor of naming accuracy for both the treated and untreated words. However, this relationship did not reach significance once baseline anomia severity was accounted for.

CONCLUSIONS

Although replication in a larger sample is warranted, results suggest that PCA treatment is similarly efficacious when delivered at different intensities. Other factors related to the quality of treatment (i.e., active ingredients such as cue-generation) may play an important role in determining treatment efficacy and must also be considered when comparing treatment intensities.

Playing With BEARS: Balancing Effort, Accuracy, and Response Speed in a Semantic Feature Verification Anomia Treatment Game

Purpose The purpose of this study was to develop and pilot a novel treatment framework called BEARS (Balancing Effort, Accuracy, and Response Speed). People with aphasia (PWA) have been shown to maladaptively balance speed and accuracy during language tasks. BEARS is designed to train PWA to balance speed-accuracy trade-offs and improve system calibration (i.e., to adaptively match system use with its current capability), which was hypothesized to improve treatment outcomes by maximizing retrieval practice and minimizing error learning. In this study, BEARS was applied in the context of a semantically oriented anomia treatment based on semantic feature verification (SFV). Method Nine PWA received 25 hr of treatment in a multiple-baseline single-case series design. BEARS + SFV combined computer-based SFV with clinician-provided BEARS metacognitive training. Naming probe accuracy, efficiency, and proportion of "pass" responses on inaccurate trials were analyzed using Bayesian generalized linear mixed-effects models. Generalization to discourse and correlations between practice efficiency and treatment outcomes were also assessed. Results Participants improved on naming probe accuracy and efficiency of treated and untreated items, although untreated item gains could not be distinguished from the effects of repeated exposure. There were no improvements on discourse performance, but participants demonstrated improved system calibration based on their performance on inaccurate treatment trials, with an increasing proportion of "pass" responses compared to paraphasia or timeout nonresponses. In addition, levels of practice efficiency during treatment were positively correlated with treatment outcomes, suggesting that improved practice efficiency promoted greater treatment generalization and improved naming efficiency. Conclusions BEARS is a promising, theoretically motivated treatment framework for addressing the interplay between effort, accuracy, and processing speed in aphasia. This study establishes the feasibility of BEARS + SFV and provides preliminary evidence for its efficacy. This study highlights the importance of considering processing efficiency in anomia treatment, in addition to performance accuracy. Supplemental Material https://doi.org/10.23641/asha.14935812.