Self-Reported Inner Speech Reflects Improvement From Language Therapy
Brielle C. Stark, Julianne M. Alexander, Emma Stockrahm, Reagan Taylor, Peyton Nielsen, Bailey BarronPurpose:
This study examined the role of inner speech—defined here as the subjective experience of covert lexical access—in naming recovery following semantic feature analysis (SFA) treatment in individuals with aphasia. Specifically, it tested whether baseline inner speech predicted treatment outcome and whether momentary changes in inner speech across the study were associated with naming success.
Method:
Eighteen individuals with poststroke aphasia completed three pretreatment naming probes, nine SFA treatment sessions targeting 30 individualized items (Treated30), and three posttreatment probes. On each naming trial, participants indicated whether they experienced inner speech prior to responding. The primary hypothesis—that pretreatment inner speech predicts posttreatment naming accuracy for treated items—was tested using logistic mixed-effects models with participant as a random effect. Exploratory analyses used trial-level mixed-effects models to examine whether changes in inner speech, aphasia severity, and psycholinguistic factors (e.g., word frequency, phoneme length) predicted naming outcomes for treated items. Generalization analyses used participant-level models to assess whether inner speech and naming improved for untreated items.
Results:
Pretreatment inner speech did not predict posttreatment naming success. In contrast, trial-level analyses revealed a strong interaction between treatment and concurrent inner speech: Items were more likely to be named correctly posttreatment when inner speech was present. This effect held after controlling for aphasia severity and psycholinguistic variables. Untreated items showed modest gains, consistent with limited generalization.
Conclusion:
Baseline inner speech did not predict treatment outcome, but after therapy, participants were much more likely to name an item correctly when they reported inner speech for that item, indicating that inner speech is a dynamic real-time marker of treatment-related lexical access.