Three questions for Dr. Thomas Wagner, traffic psychologist and Head of DEKRA’s Assessment Center for Driving Suitability
Mr. Wagner, do red traffic lights make people aggressive?
There are studies that deal with aggression in road traffic in a broader sense. They come to the conclusion that it is the interplay of several factors that leads to anger and annoyance among drivers. Whenever there is a discrepancy between desired speed and the speed that is actually possible, drivers become stressed. I.e. when the flow of traffic is severely impeded. Red traffic lights contribute to this, but so do many other conditions. The crucial point here is plausibility. If the driver does not understand why he has to wait so long at a traffic light or why a construction site is impeding his progress, his annoyance increases.
Does this also increase the risk of accidents? Can we say that the more stressed a driver is, the more likely they are to collide with another road user?
One danger of stress is that I become inattentive. I no longer pay sufficient attention to what is happening around me. The other risk factor is that when I’m emotionally on high-alert – that is, focused on fight or flight – a small spark is enough to make me explode. A small provocation is enough for me to disregard the rules and run a red light, for example.
In your view, is there a fundamental need to optimize traffic light controls?
That is certainly the case. And if you take a look around, some exellent solutions already exist abroad. For example, I’m talking about systems that show how many seconds a traffic light has left on red. Because one problem for drivers is that they don’t know how long they have to wait at a traffic light. Appropriate information would therefore take a lot of pressure out of the situation. Longer yellow phases or a flashing light before the traffic light starts again would also help to defuse the situation.