An experimental study into the ability of drivers to assimilate and retain in-vehicle traffic information

The provision of weather, road and traffic information to drivers via an in-vehicle system has potential benefits for both journey efficiency and traffic safety. However, the successful implementation of such systems relies on the ability of drivers to assimilate, retain and act upon the information received. A road-based experiment investigated the ability of drivers to assimilate and retain visually-displayed travel and traffic messages whilst driving on a busy UK motorway. Subjects were presented with messages and, either 1, 2 or 3 minutes after each message, were asked a simple question about the displayed information. Their eye glance behaviour was logged, and a post-drive questionnaire administered. It was found that retention performance was affected by the length of message and the retention interval, while eye glance behaviour changed with the type of message. The findings have been used to indicate acceptable message lengths and formats for in-vehicle information, and also to provide an indication of when messages should be displayed in relation to motorway traffic and weather events