Cognitive functions supporting learning over time in naming treatment for aphasia

Purpose Aphasia rehabilitation is a learning process that unfolds over time. Previous work has examined aphasia treatment response using pre- to post-treatment comparison, largely ignoring the unfolding learning response that occurs session-to-session. We aimed to: (1) characterize the shape of learning while individuals with aphasia received intensive anomia intervention, and (2) identify the cognitive predictors of this learning response. Method Individuals (n=39) with chronic post-stroke aphasia received intensive semantic feature analysis (SFA). Naming accuracy for trained and semantically-related, untrained words was probed daily. We used Bayesian generalized linear mixed effects models to estimate the shape of learning during SFA treatment, and to measure the influence of key cognitive functions on treatment response. Results Most treatment gains appeared early during treatment, after the first four hours of intervention. Verbal recognition and visuospatial memory were associated with the magnitude of those early treatment gains, favoring strong cognitive performers. Treatment generalization to untrained targets was present but modest, with some evidence suggesting that visuospatial recall performance may be associated with treatment generalization. Conclusions Monitoring SFA treatment response early could help inform clinicians whether patients will respond optimally to intervention. Verbal recognition and visuospatial recall support learning during treatment, helping elucidate cognitive underpinnings of learning during aphasia rehabilitation.