Toward a Usability Evaluation of BCIs

If BCIs could be considered and evaluated as assistive technology facilitating life activities, they could avoid dissatisfaction and prevent abandonment. We tested two keyboard controlled Java BCI prototypes, based on the Thought Translation Device and the P300 Speller, on 61 participants with different computer skills performing a Copy Spelling Task. We then administered usability and cognitive workload questionnaires. The results have shown significant differences in the number of performed errors, in satisfaction, and in the cognitive workload invested in the task. We found that the Thought Translation Device was more error-resistant, less stressful, and more satisfactory for the users.