Abstract
Eighty-five percent of the 137 million cell phone subscribers in the United States use their phone while driving. We report four experiments that assessed the effects of hands-free cell phone conversations on simulated driving. Our first study used a car-following paradigm and found that these conversations impaired driver's reactions to vehicles braking in front of them. Our subsequent experiments assessed the extent to which this impairment can be attributed to a withdrawal of attention from the visual scene, yielding a form of inattention blindness. We examined both explicit recognition memory and implicit perceptual memory for objects presented in the visual field while driving. Cell phone conversations impaired explicit recognition memory for roadside billboards. Eye-tracking data indicated that this was not due simply to differences in visual scanning of the driving scene, but rather was due to reduced attention to foveal information. This interpretation was bolstered by data showing that cell phone conversations impaired implicit perceptual memory for items presented at fixation. Together, these studies provide direct evidence that cell phone conversations lead to a reduction in data-driven processing for objects presented at fixation while driving. These indications of cell-phone induced inattention-blindness were obtained with a combination of visual and auditory information, suggesting that the locus of the effect is at a central attentional level and not due to structural interference or overload of a perceptual or response channel. It is also noteworthy that the reduction in processing occurred for stimuli that appeared as sudden onsets, suggesting that cell phone conversations interfere with the automatic attention-capturing properties of objects in the driving scene. We suggest that even when cell phone users are directing their gaze at objects in the driving environment that they may fail to “see” them because attention is directed elsewhere.