Measuring Cognitive Load for Adaptive Instructional Systems by Using a Pressure Sensitive Computer Mouse

Adaptive instructional systems need to understand the trainee's mental state to be effective and efficient. The measurement method that assesses the mental state has to fulfill several requirements to be useful for such a system. It has to be valid, reliable, as unobtrusive as possible, processable by technical systems, and cost-efficient. The parameters of a pressure-sensitive computer mouse duration of a mouse click, click frequency, and applied pressure during clicking are promising candidates to fulfill these requirements. To assess the parameters' sensitivity to variations in cognitive load, we conducted a repeated measures experiment with N = 16 subjects using the Warship Commander Task as a quasi-realistic simulation of command and control tasks. Results indicate that the mouse parameters could differentiate between different levels of cognitive workload. In addition, it showed similar outcomes as the NASA-TLX which was used for comparison as a subjective mea sure of workload. The results of the experiment, therefore, suggest that a pressure-sensitive computer mouse can be a useful user state analysis tool in adaptive instructional systems.