Generalization in Aphasia Treatment: A Tutorial for Speech-Language Pathologists.

PURPOSE: Generalization has been defined and instantiated in a variety of ways over the last half-century, and this lack of consistency has created challenges for speech-language pathologists to plan for, implement, and measure generalization in aphasia treatment protocols. This tutorial provides an overview of generalization with a focus on how it relates to aphasia intervention, including a synthesis of existing principles of generalization and examples of how these can be embedded in approaches to aphasia treatment in clinical and research settings. METHOD: Three articles collectively listing 20 principles of generalization formed the foundation for this tutorial. The seminal work of Stokes and Baer (1977) focused attention on generalization in behavioral change following treatment. Two aphasia-specific resources identified principles of generalization in relation to aphasia treatment (Coppens & Patterson, 2018; Thompson, 1989). A selective literature review was conducted to identify evidence-based examples of each of these 20 principles from the extant literature. RESULTS: Five principles of generalization were synthesized from the original list of 20. Each principle was supported by studies drawn from the aphasia treatment literature to exemplify its application. CONCLUSIONS: Generalization is an essential aspect of meaningful aphasia intervention. Successful generalization requires the same dedication to strategic planning and outcome measurement as the direct training aspect of intervention. Although not all people with aphasia are likely to benefit equally from each of the principles reviewed herein, our synthesis provides information to consider for maximizing generalization of aphasia treatment outcomes. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.24714399.

Applying Appraisal Tools in Aphasia Systematic Reviews: A Tutorial.

PURPOSE: A systematic review (SR) represents a rigorous process of identifying and summarizing current research to answer specific clinical questions. Not all SRs present high-quality information, because they do not adhere to established standards of conduct or reporting. This tutorial aims to (a) describe two tools developed in epidemiology for reporting (PRISMA 2020; Preferred Reporting Items for Systematic Reviews and Meta-Analyses) and appraising (AMSTAR 2; A MeaSurement Tool to Assess Systematic Reviews) SRs and (b) exemplify the use of AMSTAR 2. First, we describe the intents of PRISMA 2020 and AMSTAR 2 and compare the items on each checklist. Next, we apply the AMSTAR 2 list of domains to critically appraise methodological quality in two randomly selected SRs, which describe aphasia treatment. Appraisal results are reported, including the AMSTAR 2 ratings for overall confidence in the results of each review. For each SR, the overall rating was critically low, indicating that within the seven critical domains of AMSTAR 2, the SR had more than one critical weakness. CONCLUSIONS: While PRISMA 2020 is a tool to guide preparation of SRs, to examine SR quality, the AMSTAR 2 is the tool of choice. Applied to two current aphasia treatment SRs, the AMSTAR 2 demonstrates that although both SRs were thorough, thoughtful summaries of a body of aphasia treatment literature, they did not achieve high ratings for methodological quality. Clinicians reading SRs are advised to familiarize themselves with quality assessment tools to assure that an SR meets expected criteria to document internal and external validity of the SR process, so resulting findings can be confidently applied for patients with aphasia.

Grey and white matter correlates of picture naming: evidence from a voxel-based lesion analysis of the Boston Naming Test.

A number of recent studies utilizing both functional neuroimaging and lesion analysis techniques in neurologic patients have produced conflicting results with respect to the neural correlates of picture naming. Picture naming involves a number of cognitive processes, from visual perception/recognition to lexical-semantic retrieval to articulation. This middle process, the ability to retrieve a name associated with an object, has been attributed in some cases to posterior portions of the left lateral temporal lobe and in other cases, to anterior temporal cortex. In the current study, we used voxel-based lesion symptom mapping (VLSM) to identify neural correlates of picture naming in a large sample of well-characterized left hemisphere (LH) patients suffering from a range of naming deficits. We tested patients on the Boston Naming Test (BNT), a clinical, standardized measure of picture naming that is widely used in both clinical and research settings. We found that overall performance on the BNT was associated with a network of LH regions that included significant portions of the left anterior to posterior middle temporal gyrus (MTG) and superior temporal gyrus (STG) and underlying white matter, and extended into left inferior parietal cortex. However, when we added covariates to this analysis that controlled for deficits in visual recognition and motor speech in order to isolate brain regions specific to lexical-semantic retrieval, the significant regions that remained were confined almost exclusively to the left mid-posterior MTG and underlying white matter. These findings support the notion that a large network in left peri-Sylvian cortex supports picture naming, but that the left mid-posterior MTG and underlying white matter play a critical role in the core ability to retrieve a name associated with an object or picture.

Intensity of aphasia therapy: evidence and efficacy.

Determining the optimal amount and intensity of treatment is essential to the design and implementation of any treatment program for aphasia. A growing body of evidence, both behavioral and biological, suggests that intensive therapy positively impacts outcomes. We update a systematic review of treatment studies that directly compares conditions of higher and lower intensity treatment for aphasia. We identify five studies published since 2006, review them for methodologic quality, and synthesize their findings with previous ones. For both acute and chronic aphasia, results at the language impairment and communication activity/participation levels tend to be more equivocal than previously demonstrated, with no clear differences between intensive and nonintensive treatment emerging across studies. Future research directions are discussed including research design, definitions of treatment intensity, and behavioral and biological measurement of short- and long-term changes following implementation of an intensive treatment.

Evidence-based systematic review: effects of intensity of treatment and constraint-induced language therapy for individuals with stroke-induced aphasia.

PURPOSE: This systematic review summarizes evidence for intensity of treatment and constraint-induced language therapy (CILT) on measures of language impairment and communication activity/participation in individuals with stroke-induced aphasia. METHOD: A systematic search of the aphasia literature using 15 electronic databases (e.g., PubMed, CINAHL) identified 10 studies meeting inclusion/exclusion criteria. A review panel evaluated studies for methodological quality. Studies were characterized by research stage (i.e., discovery, efficacy, effectiveness, cost-benefit/public policy research), and effect sizes (ESs) were calculated wherever possible. RESULTS: In chronic aphasia, studies provided modest evidence for more intensive treatment and the positive effects of CILT. In acute aphasia, 1 study evaluated high-intensity treatment positively; no studies examined CILT. Four studies reported discovery research, with quality scores ranging from 3 to 6 of 8 possible markers. Five treatment efficacy studies had quality scores ranging from 5 to 7 of 9 possible markers. One study of treatment effectiveness received a score of 4 of 8 possible markers. CONCLUSION: Although modest evidence exists for more intensive treatment and CILT for individuals with stroke-induced aphasia, the results of this review should be considered preliminary and, when making treatment decisions, should be used in conjunction with clinical expertise and the client's individual values.