Voice-Activated Dialing or Eating a Cheeseburger: Which is More Distracting during Simulated Driving?

We measured simulated driving performance for 26 participants who drove a fixed distance while continuously eating a cheeseburger, operating an automobile CD player, reading directions, or using a voice-activated dialing system to place calls on a mobile phone. Performance was also measured while participants drove without doing other tasks. Participants made the most lane-keeping errors, minimum speed violations, and glances away from the road while reading and while operating the CD player. They made significantly fewer driving errors and glances while voice-dialing the mobile phone or eating, although in both of these conditions they made more driving errors and glances than they did when driving without doing any other activity. We conclude that for simulated driving, placing calls using a voice-activated dialing system is as distracting as eating a cheeseburger, but both of these activities are less distracting than continuously operating a CD player or reading directions.