Lesion site and therapy time predict responses to a therapy for anomia after stroke: a prognostic model development study

Abstract

BACKGROUND: Stroke is a leading cause of disability, and language impairments (aphasia) after stroke are both common and particularly feared. Most stroke survivors with aphasia exhibit anomia (difficulties with naming common objects), but while many therapeutic interventions for anomia have been proposed, treatment effects are typically much larger in some patients than others. Here, we asked whether that variation might be more systematic, and even predictable, than previously thought. METHODS: 18 patients, each at least 6 months after left hemisphere stroke, engaged in a computerised treatment for their anomia over a 6 week period. Using only: (a) the patients' initial accuracy when naming (to-be) trained items; (b) the hours of therapy that they devoted to the therapy; and (c) whole-brain lesion location data, derived from structural MRI; we developed Partial Least Squares regression models to predict the patients' improvements on treated items, and tested them in cross-validation. RESULTS: Somewhat surprisingly, the best model included only lesion location data and the hours of therapy undertaken. In cross-validation, this model significantly out-performed the null model, in which the prediction for each patient was simply the mean treatment effect of the group. This model also made promisingly accurate predictions in absolute terms: the correlation between empirical and predicted treatment response was 0.62 (95%CI: 0.27, 0.95). DISCUSSION: Our results indicate that individuals' variation in response to anomia treatment are, at least somewhat, systematic and predictable, from the interaction between where and how much lesion damage they have suffered, and the time they devoted to the therapy.

Gesture in the eye of the beholder: An eye-tracking study on factors determining the attention for gestures produced by people with aphasia

“…Although differing in severity, most speakers with aphasia have some deficits in verbal production (e.g. impaired lexical retrieval, grammatical formulation, paraphasias, and other errors in producing language content) (Hope et al, 2021;Laine and Martin, 2013). Several theoretical models of gesture production propose that gesture and speech underlie a shared communicative intention (de Ruiter, 2000;Kita and Özyürek, 2003).…”

Gesture in the eye of the beholder: An eye-tracking study on factors determining the attention for gestures produced by people with aphasia

“…The disorder generally affects several language modalities (speaking, understanding speech, reading and writing) to various degrees. Although differing in severity, most speakers with aphasia have some deficits in speech production (Hope et al, 2021;Laine & Martin, 2013). Therefore, some patients may rely more strongly on hand gestures and produce a higher number and more informative gestures than non-brain damaged control speakers (Herrmann et al, 1988).…”