“Hands-free” systems to utilize in-vehicle cell phones and GPS units are publicly viewed as a safe practice. According to researchers, that’s not exactly true. The use of “Hands-free” devices behind the wheel is not “risk-free.”
This comprehensive cognitive distraction study was conducted by David Strayer, a team of researchers from the University of Utah, and was supported by the AAA Foundation.
A 5 point rating scale was formulated specifically for this study to determine the cognitive levels of distraction that occurred when the subjects were accomplishing specific isolated tasks including: listening to the radio, listening to an audio book, talking with a passenger, talking on a cell phone, talking on a hands-free cellular device, and utilizing a speech-to-text messaging system. These tasks were observed and analyzed to help understand their relationship to the subject’s attention, or inattention to driving.
Each of the six tasks were preformed in three different scenarios, once while not driving, once in a simulator, and once while actually driving. The following factors were observed and measured during the study: brainwave activity (EEG’s), reaction time, break reaction time, eye/head movement, and workloads.
According to the study, the tasks were rated as follows:
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