Perception and appraisal of approaching motorcycles at junctions

Why do drivers pull out in front of approaching motorcycles at t-junctions? Two possible reasons are that drivers fail to perceive the oncoming motorcycle, or that they incorrectly judge that it is safe to pull out. Two experiments were undertaken to assess these two possibilities using static pictures of t-junctions containing either a motorcycle or a car, or no approaching traffic. The approaching vehicles could be at a near, intermediate or far distance from the junction. In Experiment 1 participants were given 250 ms to spot whether a vehicle was present. At far distances motorcycles were spotted less than cars, and correct response times were slower demonstrating a problem with perceiving motorcycles. In Experiment 2 participants were given as much time as necessary to view each picture before deciding whether it would be safe to pull out in front of the approaching vehicle. While participants were more likely to pull out in front of vehicles in the far location, there was no difference between cars and motorcycles. The results suggest that perceptual errors could occur in the first fixation, though providing all the information available is fully processed there is no differentiation between vehicles.