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Too much thinking can be a road hazard


What's going on inside the car could be just as distracting as what's happening outside

Listening to the radio is OK, but thinking about whether you can afford a mortgage is out, according to a new research on safe driver behavior.

The research published in the Journal of Experimental Psychology: Applied found that it's not just what we do with our eyes, but also what's going on in the brain that matters when we are behind the wheel.

Researchers from Universidad Complutense in Spain wondered if driver eye movements, and therefore driving ability, could be affected by verbal and visualisation tasks.

Drivers were asked to perform two verbal tasks (repeating words starting with a certain letter) and two spatial-imagery tasks (imagining the letters of the alphabet, one by one, from A to Z and describing whether each letter was "open" or "closed").

To see how much attention was going towards driving, the researchers measured how often drivers checked side mirrors and the speedometer. They also measured the size of the pupil and whether the driver "fixated" on a certain object while thinking.

What they found suggests that it's important to not only keep your eyes on the road, but also your mind as well. When drivers had to do the spatial-imagery task, they tended to fixate on certain points (just as it's common to stare off into the distance when trying to remember something), and used the mirror less often.

What's happening is that the eye freezes up and the visual inspection window decreases, according to researchers. This interferes with the ability to see the peripheral environment, and the driver therefore becomes be less aware of what is going on around him or her.

The study found that driver attention was more affected by the spatial-imagery task than the verbal task.

"The potential hazard of using a cellular phone is one thing," said Dr Lois Nunes, one of the researchers. "But add in-depth conversation that requires a considerable amount of mental effort, like recalling a route on a map, performing a mathematical computation or discussing an emotional charged subject, and you compound an already risky behavior."