Testing single‐ and dual‐route computational models of auditory repetition with new data from six aphasic patients

Abstract

Background: Both single‐route and dual‐route models of spoken word production have been proposed to account for auditory repetition performance in aphasic patients.

Aims: We examined the extent to which Foygel and Dell's (2000) single‐route model and Hanley, Dell, Kay, and Baron's (2004) dual‐route model could successfully predict the repetition performance of six aphasic patients who made errors in picture naming and auditory repetition.

Methods & Procedures: The six aphasic patients were tested on a variety of linguistic tasks. The models used performance on naming and nonword repetition tasks to predict real‐word repetition scores.

Outcome & Results: All six patients performed reasonably well at nonword repetition, but showed no evidence of using a non‐lexical route when repeating real words. The repetition performance of all six patients was therefore better simulated by the single‐route model than the dual‐route model.

Conclusion: Although the dual‐route model successfully predicted the real‐word repetition performance of the two patients reported by Hanley et al. (2004), it overestimated the performance of the six patients reported here. If the dual‐route model is correct, then only a minority of patients appear to benefit from using the non‐lexical route when repeating real words.