Does the Color of an Approaching Vehicle Affect Judgments of Time-to-Collision?

Prior research suggests that vehicles with longer-wavelength or lighter colors are associated with faster perceived speeds compared to shorter-wavelength or darker colors, but TTC estimates were not measured. In the current study, participants viewed a simulated traffic scene in which a red or blue vehicle approached for 3 s and disappeared. Participants pressed a button when they believed the vehicle would reach their position. Red vehicles were judged to arrive sooner (TTC was underestimated) than blue vehicles (TTC was overestimated), but only when TTC was 4 s. Results suggest that vehicle color may be used as a heuristic cue to judge TTC when cognitive motion extrapolation demands are putatively higher.