Age and Attentional Capacity

Abstract

Summary: Accident and fatality rates begin to increase after age 55. Previous research indicated only weak relationships between crash involvement and poor acuity. The other factor that may influence driving performance is impaired attentional function. Green and Bavelier (2003) showed that action-video-game players have greater attention capacity than non-video-game players. More important, non-video-game players can be trained to enhance the capacity of visual attention and its spatial distribution. In that study, all participants were young adults (aged from 18 to 23). It is not clear whether the reduced driving capability of older adults is due to a decreased attention capacity. In this paper, attention capacity of young and older drivers was examined using a flanker task paradigm. Participants were asked to respond to two shapes (diamond/square) in one of six circles arranged in a ring. At the same time, a distractor (a square/a diamond) was displayed on the left or the right of the ring. The workload of the task was manipulated by presenting different shapes in all the other circles or only one shape was present in the ring. The influence of the irrelevant shape on the performance (flanker effect) under different load conditions was compared between older and younger drivers. Consistent with previous research, the reaction time under the high-load condition was longer than in the low-load condition and older drivers' reaction time was slower than younger drivers'. However, for both age groups, flanker effect only existed for the low-load condition and tends to disappear in the high-load condition.