Multimodal urgency coding: auditory, visual, and tactile parameters and their impact on perceived urgency

Through a series of investigations involving different levels of contextual fidelity we devel- oped scales of perceived urgency for several dimensions of the auditory, visual, and tactile modalities. Psychophysical ratings of perceived urgency, annoyance, and acceptability as well as behavioral re- sponses to signals in each modality were obtained and analyzed using Steven's Power Law to allow comparison across modalities. Obtained results and their implications for use as in-vehicle alerts and warnings are discussed.