Older drivers' visual search behaviour at intersections

Previous research has indicated that older drivers are more likely to be involved in collisions in complex traffic scenarios like intersections even if they are not more involved in accidents in general. Moreover, being more vulnerable, the older driver is generally at higher risk of sustaining an injury when involved in a traffic accident. Even though there may be many factors leading to the over-involvement of older drivers in intersection collisions it is clear that the visual capacity and the ability to observe may be one of the possible causes that is of high interest to understand further. The objective of the study is to identify to what degree the visual behaviour could explain older drivers' involvement in intersection accidents. A 20 km long route composed by intersections in rural and urban environment was selected to collect both driving and eye movement data. Two groups of drivers were compared, one group aged 35-55 years and one aged 75 and above. Apart from the driving data, neck flexibility measurement was performed. The results from the neck flexibility measurement showed a clear age effect, with the older drivers showing less neck flexibility. When it comes to visual behaviour data, a difference was also found concerning the area of interest the drivers looked at; while the older drivers looked more at lines and markings on the road to position themselves in the traffic, the younger drivers looked more at dynamic objects such as other cars representing a possible threat. The difference in the visual behaviour should be used to design safety systems for all drivers to support them when they drive through an intersection. (C) 2011 Elsevier Ltd. All rights reserved.