Why do smart, calm people turn into raving lunatics behind the wheel?

Driving is dangerous and infuriating because it forces our brains to break from millions of years of evolution.

Today we dive into the psychology of driving with Traffic: Why We Drive the Way We Do (And What It Says About Us) by Tom Vanderbilt.

I stumbled upon this book years ago, and to this day it is one of the most fascinating, valuable and continuously applicable psychology books I’ve ever encountered.

The core takeaway is that driving is frustrating and dangerous because it goes very much against human nature. Our bodies evolved to survive collisions at maximum running speed (about 28 mph). As soon as you cross that threshold, your likelihood of dying rises dramatically. Our eyes and brains don’t do a good job of judging the speed of an oncoming object — which is why it’s hard to tell if those headlights in the distance are going 40 mph or 75.

Likewise, we are social creatures, and driving is inherently anti-social.

You can’t see the person in front of you. You rarely make eye contact with another driver. There’s almost no opportunity for communication or feedback. This is why our brains seek proxies for personalities in the drivers around us — and why you scream “f– you, Mercedes!” when somebody anonymously cuts you off. Absurd generalizations and stereotypes flow from the same challenge: we grasp for a meaningful narrative and personal connection, and we end up with assumptions that everybody from a certain state, gender or ethnicity is a crappy driver.

Because the human body didn’t develop to travel at the speed of a car, we’re susceptible to a range of illusions and delusions at high speeds. One of the most striking is the fact that we honestly believe we are in control of our vehicles. Contrast the fear of flying — the pilot is in control of your fate — with driving, when you’re behind the wheel. Even though tens of thousands of people die in car crashes compared to a handful in commercial plane crashes each year, we fret at the airport but don’t think twice about hopping on the highway to get there.

There are purely visual illusions, too.

The lines on the highway are 10 feet long, with 30 feet of space in between. If you looked at them standing still, they’d seem bizarrely large. But because you’re always moving 50+ mph, the developers of the highway system made the lines bigger so your brain feels like it’s moving slower. (In a study, most people guessed the line and the space between were each two feet long.)

You can also see this effect when you glance out the side window as a passenger — objects are blazing past your car almost in a blur. But look out the front window, and thanks to highway design, things seem to be moving at a normal human speed. This illusion helps drivers stay calm, but also lulls us into a false sense of security at 75 mph.

Illusions can slow us down, too.

Vanderbilt digs into a project to reduce pedestrian crashes on a busy boulevard. The road was originally designed like a highway — guardrails at each side, few safe crossing points — and seemed impersonal and disconnected from the town around it. This led to a lot of speeding, and also a lot of jaywalking, which combined for an unusually high rate of injury and death.

The town redesigned the road — without changing the lanes themselves — to make it seem more quaint. They added trees, removed guardrails, changed sidewalks and curbs, all to visually integrate the road into its human surroundings. Drivers slowed down, perceiving that they were in a place where they needed to pay attention to the hustle and bustle of their world, and pedestrians stopped dying.

There are so many gems of evolutionary psychology in this book (as well as an early look at self-driving cars) that I can scarcely scratch the surface here. Pick up Traffic (and perhaps grab the audiobook for the car), and even if it doesn’t make you a better driver, you’ll have a lot more insight into what’s happening in your brain every time you change lanes.