Age-related differences in the use of visual cues and expectancy location information in detecting driving hazards : an assessment from the ideal observer

• Main Author: Swan, Eleanor Frances
• Other Authors: Shimozaki, Steven ; Hutchinson, Claire
• Published: University of Leicester 2016
• Subjects: 150
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.677439

There is a concern with an increasing ageing driving population because older drivers have a higher crash rate/mile than other age groups. An attempt to further understand this was from the perspective of visual attention driven by cues, which carry probable information of a target's location. Cues are important in driving because hazards appear in likely, rather than random, locations and drivers have an internal representation of the spatial layout of these hazards location. The ideal observer predict the optimal performance and was employed to assess the younger and older drivers ability to 'weight' these location based on different (weighted model) or equal (equal model) likelihoods of hazards appearing in certain locations. Both age-groups also participated in a series of cueing tasks with a cue indicating the likely location (70% cue validity) of the target. The 'weight' from the ideal observer was used to assess the younger and older adults ability to use the cue probability information. Both age-groups took part in peripheral (drives automatic attention) and central (drives voluntary attention) cueing tasks with varying difficulty, i.e., set-size (2 vs. 6) and luminance (contrast threshold vs. octave-below contrast threshold). The main findings were: (1) both age groups optimally used the peripheral and central cue information when there was a smaller set-size, (2) when set-size increased, the older adults sub-optimally used the peripheral cue whilst both age-groups sub-optimally used the central cue. In the driving study, the younger drivers optimally weighted the hazard's locations whilst the older driver weighted the locations equally. The suggests that the older drivers had a shortcoming in locating hazards that could potentially cause a car accident, something that requires further investigation.