Purpose
The goal of this study was to examine if there was a principled way to understand the nature of rehabilitation in bilingual aphasia such that patterns of acquisition and generalization are predictable and logical.
Method
Seventeen Spanish–English bilingual individuals with aphasia participated in the experiment. For each participant, three sets of stimuli were developed for each language: (a) English Set 1, (b) English Set 2 (semantically related to each item in English Set 1), (c) English Set 3 (unrelated control items), (d) Spanish Set 1 (translations of English Set 1), (e) Spanish Set 2 (translations of English Set 2; semantically related to each item in Spanish Set 1), and (f) Spanish Set 3 (translations of English Set 3; unrelated control items). A single-subject experimental multiple baseline design across participants was implemented. Treatment was conducted in 1 language, but generalization to within- and between-language untrained items was examined.
Results
Treatment for naming on Set 1 items resulted in significant improvement (i.e., effect size >4.0) on the trained items in 14/17 participants. Of the 14 participants who showed improvement, within-language generalization to semantically related items was observed in 10 participants. Between-language generalization to the translations of trained items was observed in 5 participants, and between-language generalization to the translations of the untrained semantically related items was observed in 6 participants.
Conclusion
The results of this study demonstrated within- and between-language patterns that were variable across participants. These differences are indicative of the interplay between facilitation (generalization) and inhibition.