A report by University of Utah researchers found texting on a cell phone while driving is six times more dangerous than talking on a cell phone while on the road. The researchers used a driving simulator to determine that people who texted and drove were far less likely to brake on time, were liable to follow too closely behind other vehicles and experienced delayed reaction time. The study found that compared with drivers’ median reaction time when talking and driving (an increase of nine percent compared to the driving-only condition), reaction time shot up by 30 percent when drivers were texting.
Participants in the study were 40 young adults ranging in age from 19 to 23 years; 21 years was the average age. Among the participants, 20 were women and 20 were men. All participants had normal or corrected-to-normal visual acuity, normal color vision and a valid, nonprobationary driver’s license, and had an average of 4.75 years of driving experience with a range three to seven years. The participants were instructed to retrieve the messages and to respond to them verbally, and effects on driving behavior were measured in terms of time for braking onset. The study found while participants were reading text messages, the braking times were significantly longer and drivers drove slower than in baseline driving conditions.
During driving, the participant’s task was to follow a pace car driving in the right-hand lane of the simulated highway. In each scenario, the pace car was programmed to brake at 42 randomly selected intervals and would continue to decelerate until the participant depressed the brake pedal, at which point the pace car would begin to accelerate to normal freeway speeds. If the participant failed to depress the brake, he or she would eventually collide with the pace car. The brake lights of the pace car were illuminated throughout the deceleration interval, the paper noted.
The researchers pointed out the locus of control of text messaging compared with talking on a cell phone while operating a motor vehicle is driver controlled; that is, the driver can choose when to enter a text message, whereas a driver talking on a cell phone is more pressured into “maintaining a particular pace of response”. This situation provides drivers with the possibility of choosing times of relatively little demand of the driving task (little surrounding, smooth flowing traffic) for text messaging. According to a survey conducted by Telstra in Australia, 30 percent of the respondents admitted to having sent text messages while driving a vehicle, and almost 20 percent regularly send text messages while driving.
A copy of the report, “Text Messaging During Simulated Driving,” written by Frank A. Drews, Hina Yazdani, Celeste N. Godfrey, Joel M. Cooper, and David L. Strayer, of the University of Utah, was first published in “Human Factors,” a professional journal of the Santa Monica, Calif.-based Human Factors and Ergonomic Society (HFES). The report is offered as a free download via the organization’s Web site.
