Transfer effects of recursive self-feedback on connected speech production in patients with chronic nonfluent aphasia: Preliminary results

Abstract

ABSTRACT Background Persons with nonfluent aphasia (PWNA) have deficits with online feedback for speech error detection and correction which have debilitating effects on language relearning in learned and novel contexts. Previous studies have shown that aphasia treatments that combine PWNA’s offline self-feedback and external feedback from speech-language pathologists (SLPs) improve language production in learned and novel contexts. However, it remains unclear whether PWNA can use their offline self-feedback alone during treatments that generalizes to improvement in connected speech production. Here, we examine generalization effects of recursive self-feedback on PWNA’s connected speech production. Recursive self-feedback utilizes offline self-feedback loops alone to help PWNA optimize their error monitoring and correction abilities for language production in learned and novel contexts. Method A crossover design was used to investigate generalization effects of two treatments on connected speech production in four PWNA. These treatments comprised script production with recursive self-feedback and script production with external feedback. Employing a mobile health approach, treatments were remotely administered to participants within the comfort of their homes. Practice of both treatment blocks occurred intensively over two hours per day, five days per week, spanning two to three weeks. Each treatment block featured pretreatment and posttreatment assessment phases, with the sequencing of treatment blocks evenly counterbalanced across all participants. Following the initial treatment block, a two-week period devoid of treatment preceded the commencement of the second treatment block. Untrained narrative elicitation tasks were utilized to prompt connected speech production samples from all participants during the assessment phases of each treatment block. Effect sizes per participant were computed using within-case standard mean difference analysis. Results PWNA exhibited variability in performance, showing improvement in microlinguistic measures of connected speech following both script production with recursive self-feedback and script production with external feedback. Particularly, script production with recursive self-feedback demonstrated marginally superior enhancement in connected speech measures compared to its counterpart. Conclusion The study provides preliminary evidence for generalization effects of recursive self-feedback training and external feedback training on PWNA’s connected speech production. Further research is required to corroborate the findings and to implement recursive self-feedback procedures optimized specifically for spontaneous speech.