The research assessed the effects of cellular phone conversations on driving performance. When subjects were deeply involved in cellular phone conversations using either a hand-held or hands-free device, they were more than twice as likely to miss simulated traffic signals presented at the centre of fixation than when they were not distracted by the cell phone conversation. By contrast, performance was not disrupted by listening to radio broadcasts or listening to a book on tape. One might argue that when subjects were conversing on a cell phone that they detected the simulated traffic signals, but that the responses to them were suppressed. To assess this, the implicit perceptual memory for items that were presented at fixation but called for no response were examined. Implicit perceptual memory was strong when subjects were not engaged in a cell-phone conversation but impaired when they were so engaged. It is suggested that active participation in a cell phone conversation disrupts performance by diverting attention to an engaging cognitive context other than the one immediately associated with driving.
Abstract