USABILITY TESTING BASED ON THE COGNITIVE MISMATCH EEG SIGNALS

摘要

This paper describes how electroencephalogram (EEG) signals can be utilized in usability testing, especially for evaluating the cognitive mismatch between a user's mental model and an appliance's working model. We aim to evaluate the usability of information appliances that interact with users. In addition to traditional usability testing, it is necessary to consider the user's mental state, that is, how users understand and predict an appliance's response. Two serial psychophysiological experiments were conducted to confirm whether the EEG signals obtained from a user reflect the cognitive mismatch that occurs when a user's expectations conflict with the actual response. We focused on the event-related brain potential (ERP) components measured by EEG, and we identified a positive ERP component with a peak latency of 550-600ms as an indicator of cognitive mismatch. These results suggest that the ERP component might reflect a user's mental status. By combining signals with behavioural observations, we can realize detailed evaluations that will improve product design.