By Eric Smillie

When was the last time a traffic jam changed your life? A slow moving stretch of the New Jersey Turnpike did just that for Tom Vanderbilt, making him stop and wonder: Why do we drive the way we do? Three years, scores of interviews, and a truckload of fun factoids later, his best seller, Traffic, examines the psychology of the road. We caught up with him to ?nd out what we're doing behind the wheel.

Q It turns out that the safest-looking roads are the most dangerous. Why?
A When it rains or snows, you hear warnings on the radio. On sunny days you never hear, "Drive carefully" in the weather report, but most crashes happen on dry roads. We go faster when we feel safe.

Q You argue that helmets for car occupants could cut traffic fatalities by 25 percent. What color is yours?
A There are things we just don't want to do; we're willing to accept some risk. And if people were to wear helmets, they might start to behave like race car drivers.

Q What will make us safer?
A Bringing human perception into driver'sed. A lot of what we learn there is how to put the car in gear. It doesn't get into more complex problems like lookbut-don't-see accidents, where drivers make left turns directly into motorcyclists.

Q What's next? Are you cruising the highway to find another inspiration?
A Maybe this time it'll be when I'm walking.

You’ll find resources and advice for safe driving at AAA.com/safedriving.