STEVE INSKEEP, host:
As millions of Americans drive to see family and friends this week, we're looking at road safety. New technologies and highway designs have helped to reduce deaths. Still, there are limits to what safety measures can achieve.
Mr. TOM VANDERBILT (Author, �Traffic: Why We Drive The Way We Do�): Human nature is always really the X factor in this, because where the gains have really come from, in my opinion, is simply cars have become safer and the roads have been made safer. I don't think there's been a qualitative improvement in the way people are driving.
INSKEEP: Tom Vanderbilt wrote a book about driving, and he focused a lot on the quirks of the human beings behind the wheel - humans who did not evolve to move at 60 miles an hour or faster. He says our perception of risk on the road is often at odds with reality.
Take, for example, the roundabout, a circle where cars merge and exit from several different directions. Those roundabouts unnerve many drivers.
Mr. VANDERBILT: This is the classic case of risk perception of being wrong in traffic. People fear roundabouts in America. They've been called circles of death, and nothing could be further from the truth. Part of this is simply the geometry of a roundabout. It eliminates one of the most dangerous moves you can make in traffic, which is a left turn against fast-moving oncoming traffic.
The other thing, though, is that people going into a roundabout, there are a lot of other drivers, you are not relying on signs and symbols that someone else has put there. You have to basically make your own decisions, be aware of what's going on. And this tends to not only make people feel a little bit more stressed, but thus make them more vigilant, thus, I think, they tend to act more cautiously which is a positive result.
INSKEEP: You mean you make me nervous, and consequently I will drive more safely?
Mr. VANDERBILT: Exactly. On the flip side, are these nice, you know, large signalized intersections where, oh, I've got the green, I'm going to shut my brain off and just proceed through that intersection without thinking about it a second time. And this is where you get these very dangerous T-bone collisions, often at high speed.
And this also is something that puts pedestrians at risk. A driver sees a green light: their mind says go, I've got the turn. They often then forget to see the pedestrian who's crossing in that crosswalk, who also has the right-of-way.
INSKEEP: Is this the fundamental factor in automobile safety when you get right down to it, whether the driver's brain is engaged, sort of engaged, or not engaged?
Mr. VANDERBILT: Yeah, I think these studies that are coming out, these large-scale naturalistic studies where cameras were put inside cars for a year - and we're really getting sort of all sorts of new data that was simply unnoticed -is the extent to which distraction is simply a major cause of driver error and thus the crashes.
And this is something we've always suspected but weren't quite able to really quantify, and all that data's coming in. And I think one of the things about driving is it at once very cognitively challenging, but also because we are so well practiced at it we become very good at it, it can begin to seem dull and the mind is rarely full occupied 100 percent of the time, and thus it wanders and gets you into trouble.
INSKEEP: What are some of the things that can distract me in a car or that I may allow to distract myself in the car, that are not too bad, and some that are little worse and the very worst?
Mr. VANDERBILT: Well, obviously, texting has emerged as the perfect storm -it's been called - of distraction, because it brings not only a visual distraction, a mental distraction and a tactile distraction all at once, which is something that no other technology really does. I mean, cell phones are right behind that.
But even more mundane things - the child in the back seat of the car, listening to radio, especially public radio, is a good thing in the car; it keeps your mind alert and keeps you engaged. But, you know, radio dials can present a certain hazard, which is why carmakers have moved them up to the steering wheel and try to keep your gaze forward.
But one of the strange things that showed up in one of these naturalistic studies is people simply just sort of gazing out the window, absentmindedly. I mean, this is something that you can't really legislate. You can't ask people to not daydream. But we're human, we're not robotic devices that can maintain 100 percent vigilance.
INSKEEP: There's a wonderful book of short stories out - Bonnie Joe Campbell is the author. �American Salvage� is the title, and there is a short story, basically about a car crash. And the cause of the car crash is the man who's driving is driving on a foggy road, looks sideways, sees the house of his childhood friend through the fog and is remembering things that happened to him 20 years ago while driving and drives right into an accident.
Mr. VANDERBILT: And that's the sort of thing that, you know, no study is really going to capture and it'll be coded as looked out the window or something. And I myself had a radio distraction crash many years ago, but it was tuning the radio. And I just did not notice that traffic ahead of me had stopped and I struck the back of a boat on a trailer. So, luckily, it was a clear lesson made at age 16.
And this is something I should also point out, which is that crash, in essence, was a form of feedback. And this is something that drivers lack in driving and plays into human psychology. In situations where we don't really have much feedback, overconfidence tends to really bloom. And this is a classic thing with driving, the so-called Lake Woebegone effect - where you ask a large group of people who here is an above-average driver and 100 percent of people will raise their hands.
It's statistically impossible to find the below-average drivers. They're out there somewhere but they don't own up to it.
INSKEEP: Tom Vanderbilt is author of �Traffic: Why We Drive The Way We Do and What It Says About Us.� The book is now out on paperback and you can read an excerpt at NPR.org. Mr. Vanderbilt, thanks very much.
Mr. VANDERBILT: Thank you.