Effects of distributed practice and criterion level on word retrieval in aphasia

Asynchronous, online spaced-repetition training alleviates word-finding difficulties in aphasia

Word-finding difficulties for naming everyday objects are often prevalent in aphasia. Traditionally, treating these difficulties has involved repeated drilling of troublesome items with a therapist. Spaced repetition schedules can improve the efficiency of such training. However, spaced repetition in a therapy environment can be both difficult to implement and time-consuming. The current study evaluated the potential utility of automated, asynchronous, online spaced repetition training for the treatment of word-finding difficulties in individuals with aphasia. Twenty-one participants completed a two-week training study, completing approximately 60 minutes per day of asynchronous online drilling. The training items were identified using a pretest, and word-finding difficulties were evaluated both at the end of training (i.e., a post-test) and four weeks later (i.e., a retention test). The trained items were separated into three different spaced-repetition schedules: (1) Short-spacing; (2) Long-spacing; and (3) Adaptive-spacing. At the retention-test, all trained items outperformed non-trained items in terms of accuracy and reaction time. Further, preliminary evidence suggested a potential reaction time advantage for the adaptive-spacing condition. Overall, online, asynchronous spaced repetition training appears to be effective in treating word-finding difficulties in aphasia. Further research will be required to determine if different spaced repetition schedules can be leveraged to enhance this effect.

Expressive recall and recognition as complementary measures to assess novel word learning ability in aphasia

Novel word learning ability has been associated with language treatment outcomes in people with aphasia (PWA), and its assessment could inform prognosis and rehabilitation. We used a brief experimental task to examine novel word learning in PWA, determine the value of phonological cueing in assessing learning outcomes, and identify factors that modulate learning ability. Twelve PWA and nineteen healthy controls completed the task, and recall and recognition tests of learning ability. Most PWA showed comparable learning outcomes to those of the healthy controls. Learning assessed via expressive recall was more clearly evidenced with phonological cues. Better single word processing abilities and phonological short-term memory and higher integrity of the left inferior frontal gyrus were related to better learning performance. Brief learning tasks like this one are clinically feasible and hold promise as screening tools of verbal learning in PWA once validated and evaluated for their capacity to predict treatment outcomes.

Theory-driven treatment modifications: A discussion on meeting the linguistic, cognitive, and psychosocial needs of individual clients with aphasia

There is a growing body of literature demonstrating that language rehabilitation can improve naming impairments for individuals with aphasia. However, there are challenges applying evidence-based research to clinical practice. Well-controlled clinical studies often consist of homogenous samples and exclude individuals who may confound group-level results. Consequently, the findings may not generalize to the diverse clients serviced by speech-language therapists. Within evidence-based guidelines, clinicians can leverage their experiences and theoretical rationale to adapt interventions to meet the needs of individual clients. However, modifications to evidence-based interventions should not alter aspects of treatment that are necessary to produce change within the treatment target. The current discussion paper uses errorless learning, errorful learning, and retrieval practice for naming in aphasia to model how treatment theories can guide clinicians in making theory-informed modifications to interventions. First, we briefly describe the learning mechanisms hypothesized to underlie errorless learning, errorful learning, and retrieval practice. Next, we identify ways clinicians can provide targeted supports to optimize learning for individual clients. The paper ends with a reflection on how well-defined treatment theories can facilitate the generation of practice-based evidence and clinically relevant decision making.

Errorless, Errorful, and Retrieval Practice for Naming Treatment in Aphasia: A Scoping Review of Learning Mechanisms and Treatment Ingredients

PURPOSE

Increasingly, mechanisms of learning are being considered during aphasia rehabilitation. Well-characterized learning mechanisms can inform "how" interventions should be administered to maximize the acquisition and retention of treatment gains. This systematic scoping review mapped hypothesized mechanisms of action (MoAs) and treatment ingredients in three learning-based approaches targeting naming in aphasia: errorless learning (ELess), errorful learning (EFul), and retrieval practice (RP). The rehabilitation treatment specification system was leveraged to describe available literature and identify knowledge gaps within a unified framework.

METHOD

PubMed and CINHAL were searched for studies that compared ELess, EFul, and/or RP for naming in aphasia. Independent reviewers extracted data on proposed MoAs, treatment ingredients, and outcomes.

RESULTS

Twelve studies compared ELess and EFul, six studies compared ELess and RP, and one study compared RP and EFul. Hebbian learning, gated Hebbian learning, effortful retrieval, and models of incremental learning via lexical access were proposed as MoAs. To maximize treatment outcomes within theorized MoAs, researchers manipulated study ingredients including cues, scheduling, and feedback. Outcomes in comparative effectiveness studies were examined to identify ingredients that may influence learning. Individual-level variables, such as cognitive and linguistic abilities, may affect treatment response; however, findings were inconsistent across studies.

CONCLUSIONS

Significant knowledge gaps were identified and include (a) which MoAs operate during ELess, EFul, and RP; (b) which ingredients are active and engage specific MoAs; and (c) how individual-level variables may drive treatment administration. Theory-driven research can support or refute MoAs and active ingredients enabling clinicians to modify treatments within theoretical frameworks.

An examination of retrieval practice and production training in the treatment of lexical-semantic comprehension deficits in aphasia

OBJECTIVE

Little research has addressed the treatment of lexical-semantic comprehension deficits (i.e., difficulty retrieving the meanings of words) in people with aphasia (PWA). Research suggests that practice retrieving names for depicted objects from long-term memory (production-based retrieval practice) more strongly benefits word retrieval for production in PWA compared to errorless learning (i.e., word repetition), which eschews retrieval practice. This study assessed whether production-based and comprehension-based retrieval practice enhance performance on errorful word-comprehension items in PWA measured relative to nonretrieval forms of training and untrained control items.

METHOD

In a within-participant group study of PWA, errorful comprehension items were assigned to (a) a production-based training module (retrieval practice vs. errorless learning); (b) a comprehension-based training module (a receptive form of retrieval practice vs. restudy). Each module comprised one training session and a 1-day and 1-week comprehension posttest on the module's trained items and an untrained item set.

RESULTS

The comprehension module conditions produced similar and superior posttest performance relative to untrained items. Both production module conditions improved posttest performance relative to untrained items, with retrieval practice conferring more durable learning and generalization indicative of refinement of semantic representations compared to errorless learning.

CONCLUSIONS

Results suggest comprehension- and production-based forms of training are both beneficial for improving lexical-semantic deficits in aphasia, with production-based retrieval practice conferring additional benefits to the targeted deficit compared to errorless learning. Future studies should examine these learning factors in schedules of training more commensurate with clinical practice and in other neurological populations (e.g., semantic dementia). (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Applying adaptive distributed practice to self-managed computer-based anomia treatment: A single-case experimental design

INTRODUCTION

There is a pressing need to improve computer-based treatments for aphasia to increase access to long-term effective evidence-based interventions. The current single case design incorporated two learning principles, adaptive distributed practice and stimuli variability, to promote acquisition, retention, and generalization of words in a self-managed computer-based anomia treatment.

METHODS

Two participants with post-stroke aphasia completed a 12-week adaptive distributed practice naming intervention in a single-case experimental design. Stimuli variability was manipulated in three experimental conditions: high exemplar variability, low exemplar variability, and verbal description prompt balanced across 120 trained words. Outcomes were assessed at 1-week, 1-month, and 3-months post-treatment. Statistical comparisons and effect sizes measured in the number of words acquired, generalized, and retained were estimated using Bayesian generalized mixed-effect models.

RESULTS

Participants showed large and robust acquisition, generalization, and retention effects. Out of 120 trained words, participant 1 acquired ∼77 words (trained picture exemplars) and ∼63 generalization words (untrained picture exemplars of treated words). Similarly, participant 2 acquired ∼57 trained words and ∼48 generalization words. There was no reliable change in untrained control words for either participant. Stimuli variability did not show practically meaningful effects.

CONCLUSIONS

These case studies suggest that adaptive distributed practice is an effective method for re-training more words than typically targeted in anomia treatment research (∼47 words on average per Snell et al., 2010). Generalization across experimental conditions provided evidence for improved lexical access beyond what could be attributed to simple stimulus-response mapping. These effects were obtained using free, open-source flashcard software in a clinically feasible, asynchronous format, thereby minimizing clinical implementation barriers. Larger-scale clinical trials are required to replicate and extend these effects.

Successive Relearning: An Underexplored but Potent Technique for Obtaining and Maintaining Knowledge

Successive relearning involves practicing a task until it is performed correctly and then practicing it again until it is performed correctly during other spaced practice sessions. Despite its widespread use outside of education, few students use this approach to obtain and maintain knowledge in formal educational settings. We review evidence that demonstrates its potency and emphasize how investigations of successive relearning will shift research agendas away from single-session studies in which time on task is fixed toward studies involving multiple practice sessions in which time on task is tailored for students and is treated as an outcome variable of interest. Doing so arguably will align the outcomes of cognitive-education research with real-world learning objectives by revealing not only the benefits of using successive relearning (or any learning technique) but also the time required to obtain those benefits.

Get in Sync: Active Ingredients and Patient Profiles in Scripted-Sentence Learning in Spanish Speakers With Aphasia

PURPOSE

Script training is a well-established treatment for aphasia, but its evidence comes almost exclusively from monolingual English speakers with aphasia. Furthermore, its active ingredients and profiles of people with aphasia (PWA) that respond to this treatment remain understudied. This study aimed to adapt a scripted-sentence learning protocol to Colombian Spanish speakers with aphasia, investigate speech entrainment (i.e., unison production of sentences) as an active ingredient for scripted-sentence learning, and identify patient profiles associated with better scripted-sentence learning.

METHOD

Fourteen monolingual Spanish speakers with aphasia learned a set of 30 sentences. To examine speech entrainment as an active ingredient for scripted-sentence learning, we investigated whether sentences containing externally added rhythmic cues (involving stress-aligned vs. metronomic rhythmic cues) would result in better scripted-sentence learning compared with control sentences. Learning was measured via postsession probes and analyzed using mixed-effects logistic regression models. The relationship between scripted-sentence learning and baseline language and rhythmic processing measures was also examined.

RESULTS

Significant scripted-sentence learning over time indicated a successful adaptation of a script-training protocol to Spanish. PWA learned significantly more scripted sentences in the rhythmically enhanced conditions compared with the control condition. There were no differences between rhythmically enhanced conditions (stress-aligned vs. metronomic). In terms of patient profiles, it was found that PWA with more severe aphasia demonstrated larger learning gains, but rhythmic processing showed little association with learning estimates.

CONCLUSIONS

To our knowledge, this study provides the first adaptation of a scripted-sentence learning protocol for monolingual Spanish speakers with aphasia, demonstrating cross-linguistic benefits of script training interventions. Highlighting rhythmic features during speech entrainment facilitated scripted-sentence learning in Spanish speakers with aphasia, suggesting that speech entrainment may be an active ingredient for scripted-sentence learning. More severe aphasia was associated with better scripted-sentence learning, suggesting that more severely impaired individuals are likely to benefit most from this treatment.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.19241847.

Treatment of the Linguistic and Temporal Components of Lexical Activation to Improve Word Retrieval in Aphasia

Current approaches to treatments for word processing impairments in aphasia emphasize two components to target, the linguistic content, semantic or phonological representations of words, and the processing component, access to and retrieval of those representations. In this study, we explore these two components of a treatment to improve lexical activation that supports access and retrieval of word representations. Five people with aphasia participated. The treatment task was repetition of concrete word pairs after a 5-s response delay which was intended to provide practice in maintaining activation of the words for that 5-s period before reproducing them. Two of the five participants demonstrated a difficulty in maintaining activation of single words in repetition, with accuracy decreasing significantly after the 5-s interval. The treatment was applied to all participants, however, to determine if its benefit was specific to those with the activation maintenance impairment. Results confirmed that the activation maintenance treatment in the context of this repetition task led to more treatment gains for the two participants who demonstrated this specific impairment. They made gains on four of the nine measures compared to improvements on one to two measures for the other participants. A second question addressed in this study was the relative importance of the item component (linguistic content) of the treatment and the processing component, maintenance of activation. To that end, there were two conditions of treatment probes, (1) repeated content for all treatment, immediate post-treatment and 3-month maintenance probes and (2) novel content for probes in these three phases of treatment. Only one participant showed significant improvement in treatment when items were novel for all probes. We discuss the possibility that this outcome reflects a more specific deficit in the temporal processing component of lexical activation compared to the two other participants who showed better performance on probes with repeated items in treatment and post-treatment phases. Clinical implications of this study and directions of future research are discussed.

Effortful Retrieval Practice Effects in Lexical Access: A Role for Semantic Competition

Word retrieval difficulty (lexical access deficit) is prevalent in aphasia. Studies have shown that practice retrieving names from long-term memory (retrieval practice) improves future name retrieval for production in people with aphasia (PWA), particularly when retrieval is effortful. To explicate such effects, this study examined a potential role for semantic competition in the learning mechanism(s) underlying effortful retrieval practice effects in lexical access in 6 PWA. Items were trained in a blocked-cyclic naming task, in which repeating sets of pictures drawn from semantically-related versus unrelated categories underwent retrieval practice with feedback. Naming accuracy was lower for the related items at training, but next-day accuracy did not differ between the conditions. However, greater semantic-relatedness of an item to its set in the related condition was associated with lower accuracy at training but higher accuracy at test. Relevance to theories of lexical access and implications for naming treatment in aphasia are discussed.

Dose effects in behavioural treatment of post-stroke aphasia: a systematic review and meta-analysis

PURPOSE

Aphasia is a debilitating chronic acquired language disorder that impacts heavily on a person's life. Behavioural treatments aim to remediate language processing skills or to enhance communication between the person with aphasia and others, and a number of different treatments are efficacious. However, it is unclear how much of a particular treatment a person needs in order to optimise recovery of language and communication skills following stroke.

MATERIALS AND METHODS

Systematic search for and meta-analysis of experimental studies that directly compared different amounts of the same behavioural aphasia treatment, following PRISMA guidelines.

RESULTS

Treatment dose research in aphasia is an emerging area. Just six studies comparing different doses of the same intervention met all criteria for inclusion. Evidence from these studies was synthesised and meta-analysed, where possible. Meta-analyses were inconclusive due to limited data; however, there are indications that suggest increased dose may confer greater improvement on language and communication measures, but with diminishing returns over time. Aphasia severity and chronicity may affect dose-response relationships.

CONCLUSIONS

There is currently insufficient evidence to determine the effect of dose on treatment response. A dedicated and coordinated research agenda is required to systematically explore dose-response relationships in post-stroke aphasia interventions.A video abstract is available in the Supplementary Material.Implications for rehabilitationThe investigation of the effect of dose on treatment outcomes in post-stroke aphasia is an emerging research area with few studies reporting comparison of different amounts of the same intervention.In the acute phase of recovery following stroke, higher doses of treatment provided over short periods may not be preferable, tolerable, or superior to lower doses of the same treatment.In the chronic phase, providing additional blocks of treatment may confer additional benefit for some people with aphasia but with diminishing returns.People with chronic aphasia can achieve and maintain significant gains in picture naming after a relatively brief period of high-dose treatment.