Aging and the Effects of Conversation With a Passenger of a Caller on Simulated Driving Performance

Abstract

The current study investigates the effects that conversation has on driving performance of older and younger drivers. In addition, the effects that the location of the conversation partner has on driving performance are also being explored. Furthermore, the quality and accuracy of the speech task were investigated as well as the extent of participant's involvement in the speech task in the form of memory recall. 96 pairs (driver and their conversation partner) of older and younger participants engaged in a story retelling task in a driving simulator. The results showed better lane keeping and more stable velocity control when drivers conversed with their partner compared to driving only. Drivers also showed faster average velocity under single-task than under dual-task conditions. Older drivers showed evidence of modulation in difficult driving conditions suggesting that they compensate for their declining perceptual and cognitive abilities through changes in driving behavior. Drivers exhibited a cost in accuracy of speech task performance when driving, providing evidence of prioritization. The results showed a decline in the accuracy of story telling by drivers and in the drivers' memory for stories told to them by their non-driving partners. Also, speech production suffered an additional cost when the difficulty of driving increased. Drivers produce more fluent speech when conversing with cell-phone caller than with passenger, although the location of conversation partner did not impact driving performance.