Texting while driving is riskier than talking on a cell phone or with another passenger, has been shown in a new study by University of Utah.
In the study, Frank Drews and colleagues found that texters in a driving simulator had more crashes, responded more slowly to brake lights on cars in front of them, and showed impairment in forward and lateral control than did drivers who talked on a cell phone while driving or drove without texting.
They found that attention patterns differ for drivers who text versus those who converse on a cell phone.
In the latter case, the researchers say, "drivers apparently attempt to divide attention between a phone conversation and driving, adjusting the processing priority of the two activities depending on task demands."
Howeverm texting requires drivers to switch their attention from one task to the other. When such attention-switching occurs as drivers compose, read, or receive a text, their overall reaction times are substantially slower than when they're engaged in a phone conversation.
The type of texting activity also appears to make a difference; in this study, reading messages affected braking times more than did composing them.
To find why and how much drivers are impaired during texting, the researchers engaged 20 men and 20 women between the ages of 19 and 23 in both a single task (straight driving) and a dual task (driving and texting) in a high-fidelity simulator.
The participants, experienced texters with an average of 4.75 years of driving experience, received and sent messages while the researchers observed their brake onset time, following distance, lane maintenance, and collisions.
The crash risk attributable to texting is substantial. One possible explanation is that drivers who text tend to decrease their minimum following distance and also experience delayed reaction time.
The study has been published in the journal Human Factors.