Common wisdom might suggest that a heads up display on your vehicle is safer than glancing down at the dash. What if common wisdom is wrong?
A study at the University of Toronto suggests just that, working from the premise that HUDs could indeed make driving more dangerous rather than less, based on the idea that dealing with the additional visual information was a challenge to our attention that increased the difficulty of driving.
To test this, participants were given a set of computer based trials where they had to report on a number of randomly arranged spots on a screen. Randomly, a secondary stimulus in the form of a square was flashed up onscreen, and respondents had to indicate if they saw it or not.
If the square was entirely absent, accuracy in counting was good, but when it was present, accuracy dropped, suggesting distraction from the core task. This only worsened if there were more spots onscreen.
The issue, according to the researchers, is that in a vehicle HUD situation, the difference between an arrow that might indicate a turning scenario and an alert that might indicate you're going to crash into a tree could be muddled or misinterpreted due to the quantity of data provided and the distraction from the core driving experience.
Digital messages on windshields make driving less safe [University Of Toronto via Slashgear]