Measuring Cognitive Distraction in the Automobile II: Assessing In-Vehicle Voice-Based Interactive Technologies

Car crashes rank among the leading causes of death in the United States. Acknowledgments We acknowledge the assistance of Founded in 1947, the AAA Foundation in Washington, D.C. is a not-for-profit, publicly supported charitable research and education organization dedicated to saving lives by preventing traffic crashes and reducing injuries when crashes occur. Funding for this report was provided by voluntary contributions from AAA/CAA and their affiliated motor clubs, from individual members, from AAA-affiliated insurance companies, as well as from other organizations or sources. This publication is distributed by the AAA Foundation for Traffic Safety at no charge, as a public service. It may not be resold or used for commercial purposes without the explicit permission of the Foundation. It may, however, be copied in whole or in part and distributed for free via any medium, provided the AAA Foundation is given appropriate credit as the source of the material. The AAA Foundation for Traffic Safety assumes no liability for the use or misuse of any information, opinions, findings, conclusions, or recommendations contained in this report. If trade or manufacturer's names are mentioned, it is only because they are considered essential to the object of this report and their mention should not be construed as an endorsement. The AAA Foundation for Traffic Safety does not endorse products or manufacturers. Abstract The goal of the current research was to measure and understand cognitive distraction stemming from voice-based technologies in the vehicle. Three controlled experiments evaluated 1) a baseline single-task condition, 2) issuing simple voice-based car commands, 3) listening to e-mail/text messages read by a " natural " pre-recorded human voice, 4) listening to e-mail/text messages read by a " synthetic " computerized text-to-speech system, 5) listening and composing replies to e-mail/text messages read by a " natural " voice, 6) listening and composing replies to e-mail/text messages read by a " synthetic " voice, 7) interacting with a menu-based system with perfect reliability, 8), interacting with a menu-based system with moderate reliability, and 9) using " hands-free " Siri to listen to and send text messages, update Facebook or Twitter status, and modify and review calendar appointments. Because each task allowed the driver to keep his or her eyes on the road and hands on the steering wheel, any impairment to driving must be caused by the diversion of attention from the task of operating the motor vehicle. We used a combination …