Cross-cultural effects on drivers’ use of explicit and implicit communicative cues to predict intentions of other road users

This study explored whether British and Malaysian drivers differ in their use of explicit (turn signals) and implicit (e.g., vehicle position, speed) communicative cues when judging the intention of other road users. Participants viewed videoclips of car drivers and motorcyclists who either continued straight or turned into a junction. The clips terminated immediately prior to any manoeuvre being made and participants were asked to judge whether or not the vehicle would turn. Explicit signals (turn indicators) were manipulated such that valid signals were made 50% of the time. Although both groups of drivers were more accurate on validly signalled trials, British drivers were more affected by signal validity, performing particularly poorly on invalid trials. British drivers were better at judging intentions of cars than motorcycles, whereas Malaysians performed better for motorcycles than cars on invalid trials. We conclude that British drivers heavily rely on explicit signals when judging intention whereas Malaysian drivers are more attuned to implicit signals. Familiarity with vehicle type may also impact performance, especially where cues are ambiguous. Implications for driving abroad and autonomous vehicles are discussed.