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

Abstract

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.

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

“…Aphasia severity . Aphasia severity is commonly recognized as an influential factor for language recovery (e.g., Kristinsson et al, 2022 ; Plowman et al, 2012 ; Watila & Balarabe, 2015 ). The cortical organization of language relies on dynamic interactions across temporal, parietal, and frontal brain regions ( Hickok & Poeppel, 2007 ; Tourville & Guenther, 2011 ).…”

Therapies and Challenges in the Post-Stroke Aphasia Rehabilitation Arena: Current and Future Prospects

“…Hence, it would be reasonable to expect limited language recovery in older PWA. Indeed, there are studies that have found that people that experience aphasia at a younger age tend to have better outcomes in comparison to people that manifest aphasia at older ages e.g., [ 93 , 94 ]. Nevertheless, the association between age and recovery varies between studies [ 95 , 96 ] and this variation may be attributed to several factors (e.g., comorbidities, differences in sample characteristics and assessment methods).…”

It is time to make neuroimaging research data beneficial to the participants

“…For example, given the complex dynamics of recovery after stroke, 3 a right hemisphere activation in an aphasic patient after a left infarct could reflect a pre‐stroke atypical language representation or could result from a post‐stroke inter‐hemispheric shift of language systems. Ideally, a within‐patient comparison between pre‐ and post‐deficit neuroimaging data would provide a much accurate depiction of brain re‐organization mechanisms, which can ultimately support the design of personalized therapies 4 . We are ushering into a new era that might make this a possibility in the light of the exponential growth in the number of participants in neuroimaging research.…”

“…Ideally, a within-patient comparison between pre-and post-deficit neuroimaging data would provide a much accurate depiction of brain re-organization mechanisms, which can ultimately support the design of personalized therapies. 4 We are ushering into a new era that might make this a possibility in the light of the exponential growth in the number of participants in neuroimaging research. Indeed, thousands of neurotypical volunteers are tested every year, mainly for research purposes, but their brain scans can soon help address other questions related to brain changes and re-organization in a novel and reliable way based on within-subject comparisons.…”