Effects of Adaptive Information Presentation

Several new approaches to assisting the driver in dealing with the complex task of the driving situation are being developed. One possibility is to give support in the secondary task with the aim of facilitating the primary driving task. In this study, the author tested whether a situation-dependent change of modality presentation for a secondary task can support time-sharing and enhance performance in the primary task. In an experiment, 42 subjects were engaged in a computer-simulated tracking task, which is a continuous task like driving a car. From time to time they also had to perform a decision-making task, which was to identify special numerical series. The task was an analogy to receiving a phone call while driving. The independent variables consisted of 1) demands of the situation (low vs. high) and 2) presentation modality of the secondary task (visual, auditory, visual + auditory; adaptive, non-adaptive). Performance was assessed through mistakes in the tracking task (lateral deviation from the central line). Additionally, the participants were asked for their subjective opinion of this system-driven change of modality presentation. Findings do not support the assumption that changing from bimodal (visual + auditory) to auditory-only presentation under high situational demands leads to best performance in the driving task. Rather, auditory-only information presentation was best under all conditions and led to the fewest mistakes in the tracking task. Moreover, subjective ratings revealed that 50% of the subjects favoured auditory-only presentation and 75% of the subjects generally preferred non-adaptive information presentation.