A study published in the journal Traffic Injury Prevention concludes that digital billboards attract and hold the gazes of drivers for far longer than a threshold that previous studies have shown to be dangerous.
The study, conducted by researchers at the Swedish National Road and Transport Research Institute and funded by the Swedish Transport Administration, found that drivers looked at digital billboards significantly longer than they did at other signs on the same stretch of road, with the digital signs often taking a driver’s eyes off the road for more than two seconds.
A well-regarded 2006 study by Virginia Tech for the National Highway Traffic Safety Administration found that anything that takes a driver’s eyes off the road for more than two seconds greatly increases the risk of a crash. The study also found that nearly 80 percent of all crashes involved driver inattention just prior to (within 3 seconds) of the crash.
The Swedish study’s authors reasoned that it’s not surprising that digital billboards attract greater attention from drivers: the signs are brighter, visible from greater distances, and display a constantly-changing series of advertisements. They concluded that digital billboards “have the potential ability to keep up the driver’s curiosity over an extended period of time.” Previous human behavior studies have shown that drivers are hardwired to notice bright, changing lights in their peripheral vision and to anticipate additional motion.
The Swedish government had given temporary authorization to erect digital billboards in 2009, but as a result of this and related studies the government ordered the removal of all digital billboards. Meanwhile in the United States these signs continue to go up at a rapid pace despite a growing body of evidence suggesting they pose a threat to traffic safety.