New research shows that people have greater difficultly maintaining a fixed speed, or keeping their car safe in a single lane when performing tasks that simulated conversing on a mobile phone, than if they were driving without the distraction. Contrary to expectation, the speaking and listening were equally distracting.
The research was conducted at the University of Illinois and will be published in the next edition of Applied Cognitive Psychology.
Almost 100 students took experiments in which they drove virtual cars. While driving they had to provide answers about the layout of buildings on their campus, or check that statements made by others about relative positions of building were correct. The researchers monitored various aspects of their driving performance while they performed these tasks.
They showed that both speaking and listening had detrimental effects on driving. Participants were poorer at maintaining a stable speed, or keeping a constant distance between themselves and other traffic than when only driving. Paradoxically, there was some indication that when drivers had to speak while driving, their lane control increased even though speed control decreased.
Before this research the expectation was that speaking would be more detrimental than listening, because speaking is often thought to be a more complex task. "Unexpectedly we found that speaking and listening had very similar detrimental effects," says lead author Tate Kubose, a postdoctoral fellow working in the Beckman Institute for Advanced Science and Technology at the University of Illinois. "These results challenge the widespread presumption that production is harder than comprehension, and the expectation that talking while driving is necessarily more disruptive than listening," says Dr Kubose.
These results support the growing body of data suggesting that it is the cognitive task of conversing via phone, in addition to the physical task of handling the equipment, that impedes a person's ability to drive safely.