posted on 2015-08-01, 00:00authored bySofia Vallila-Rohter, Swathi Kiran
Purpose Our purpose was to study strategy use during nonlinguistic category learning in aphasia.
Method Twelve control participants without aphasia and 53 participants with aphasia (PWA) completed a computerized feedback-based category learning task consisting of training and testing phases. Accuracy rates of categorization in testing phases were calculated. To evaluate strategy use, strategy analyses were conducted over training and testing phases. Participant data were compared with model data that simulated complex multi-cue, single feature, and random pattern strategies. Learning success and strategy use were evaluated within the context of standardized cognitive–linguistic assessments.
Results Categorization accuracy was higher among control participants than among PWA. The majority of control participants implemented suboptimal or optimal multi-cue and single-feature strategies by testing phases of the experiment. In contrast, a large subgroup of PWA implemented random patterns, or no strategy, during both training and testing phases of the experiment.
Conclusions Person-to-person variability arises not only in category learning ability but also in the strategies implemented to complete category learning tasks. PWA less frequently developed effective strategies during category learning tasks than control participants. Certain PWA may have impairments of strategy development or feedback processing not captured by language and currently probed cognitive abilities.
Funding
This research was made possible in part by National Institutes of Health Grants 1K18DC011517 (awarded to Swathi Kiran) and 1R21/R33DC010461 (awarded to Swathi Kiran and Sofia Vallila-Rohter). We thank all of our participants, caregivers, and relatives for contributing to this study. We also thank Elsa Ascenso, Christina Rozek, Chaleece Sandberg, and Sarah Villard for their assistance with data collection.