Visual demand of bilingual message signs displaying alternating text messages

This field study was designed to compare the visual demand of variable message signs (VMSs). Specifically, three VMS types were evaluated: a sign displaying a message alternately in Finnish and Swedish (2.0 s in each language), a sign displaying the same messages simultaneously, and a sign displaying air and road surface temperatures in Finnish. The data were collected by recording the eye movements of 38 drivers during highway driving. The main results suggested that the sign displaying alternating bilingual messages was no more demanding than the VMS displaying the same messages simultaneously. However, this conclusion is limited to those specific signs and conditions, and more research is needed for related applications in various conditions. The results further suggested that VMSs involving effective technologies might be rather demanding in comparison to the fixed signs.