Click image for demo of stimulus


Click image for demo of stimulus


Am I a safe road user? Can we trust our eyes when trying to judge the speed of oncoming traffic?

When you look down the road as a pedestrian or driver, you make a decision as to whether you have time to cross or pull-out and, providing the visibility is good, you tend to be confident in your decisions. But, we can show that there is often a systematic bias introduced into the information you use to judge the speed of approaching vehicles and you tend to make mistakes in judging the speed of vehicles that vary in size. Try the first demonstration which shows two cars of equal size, with one always travelling faster than the other, as the speed differences get smaller the task becomes harder. Then try the second demonstration which shows a motorcycle and car.

This project was featured in the ‘Live Science’ exhibit as part of the ‘Who Am I?’ gallery at the Science Museum over the summer to look at why errors of this type occur. ‘Live Science’ is an ongoing project where scientists come into the museum to carry out research using museum visitors and volunteers. Visitors viewed pictures of a car and truck or a car and a motorcycle on a computer screen and asked to decide which vehicle was traveling faster than the other by clicking one of two buttons on the screen.

Currently, our research suggests that size errors of this type are greater in younger children and may contribute to the high incidence of some types of road accident. We are currently exploring whether these errors increase in drivers over the age of 70yrs supported by an award from the Royal Society for Prevention of Accidents.

Links to Related Research

fMRI Studies: Neural systems in the processing of looming

Road Crossing


Department of Psychology, Royal Holloway, University of London, Egham, Surrey TW20 0EX
Tel/Fax : +44 (0)1784 443526/434347