Drivers beware: Billboard ahead. A new study from the University of Alberta found that language and imagery on billboards can provoke emotional responses that positively or negatively affect driving abilities. Study author Michelle Chan found a lot of literature concerning road rage, but none dealing with external emotional stimuli—so she created her own experiment with study co-author, psychology professor Anthony Singhal.

Study participants drove through one of three different courses consisting of 20 billboards. Each billboard included blocks of words that were either positive, negative or neutral. In order to test their response times, participants were to press a button the steering wheel when they encountered one of the target words.

Chan says subjects’ reaction times are typically slower when they see an emotional stimulus as opposed to a neutral one, so she wanted to test whether the same results pertained to driving response times. According to her test, drivers were, in fact, distracted when presented with emotional stimulus—emotionally charged words did indeed affect the subjects’ driving focus. According to Chan, drivers who viewed negative words slowed down while passing the signs and tended to veer from their lanes. On the other hand, drivers who viewed signs with positive phrases often sped up.

“There have been studies showing that when you’re positively stimulated, your attention broadens, so you perform better when you’re in a happy mood,” said Chan. “In my results, we also saw that when we looked at the reaction-time data in response to target words, participants actually responded faster in the positive block than in the negative block.”

Chan and Singhal aren’t the first people to expose the concept, however. Australia already bans certain emotionally-charged billboards—which makes you wonder about certain profane signage found around Las Vegas or the graphic anti-smoking and pro-life billboards on US roadways. But Chan says legislating billboards is difficult since emotional distractions can also occur from news, music and even conversations. Ultimately, she says drivers must take responsibility for their own actions behind the wheel—even if it means reducing typical stimuli such as listening to the radio or talking while driving.

“Any kind of distraction is risky when you’re driving. But there would appear to be a larger risk when it comes to emotional stimuli,” she said.

[Image via Lissandra Melo/Shutterstock]