Assessing the Impact of Alert Modalities on User Performance and Comprehension in Controlled Workload Conditions

Virtual reality (VR) is a powerful tool for investigating user experience in interactive systems by simulating experiences that are challenging to obtain in real life. However, it is crucial to design VR tasks appropriately, especially when used for training first responders who face high cognitive workloads in extreme conditions. Poorly designed VR tasks can strain cognitive resources and hinder human performance and training transfer. Therefore, careful attention must be given to developing VR tasks that enhance cognitive processing in high-cognitive workload scenarios. This study aims to assess the impact of different types and intensities of alerts on reaction time and comprehension of notifications, and task performance in a VR environment designed to induce various levels of cognitive load. Two experiments were conducted, including a remote experiment, where participants had to complete a task in which they identified matching figures while reacting to and interpreting alerts delivered through auditory, visual, and haptic channels. Results showed that, while task performance was not affected by alert type or intensity, audio alerts were the slowest to react to, indicating higher cognitive processing in alerts of that modality.