Head up displays, more commonly called HUDs, put digital images on a driver’s windshield so they can see data — speed or navigation instructions, for example — without having to take their eyes off the road. The common thought process has been that this technology makes driving safer — eyes are always forward, and devices like smartphones are tucked out of sight. A new study from the University of Toronto, however, indicates otherwise — rather than improving safety, HUDs could actually make drivers more dangerous by meddling with their attention.
The problem is that using a HUD puts two sources of data into a single visual field, and this causes the driver’s attention to be split between the two, forcing them to concentrate harder on what’s happening on the road and risk being distracted anyway when data on the display changes without warning.
In order to demonstrate this, researchers developed two tests that used visual information to assess the impact of HUDs. A visual display was presented to participants, and it showed spots ranging from one to nine. The participants had to report on the spots as they appeared.
In the second test, a square was introduced, and the participants had to keep an eye on both — the spots and, when it showed up, the square. In this case, the participants frequently failed to see the square (an average of 15 times). HUDs would prove even more distracting, as the data they display and the events on the road are far more complex.