What Can Your Brain Do While You Drive a Car?

Not very much. And nothing very well.

Your brain can’t really do anything else while you drive a car. Every time you do something else, the emphasis is on the “else.” While you’re checking your phone, you’re not driving anymore. The car is on autopilot.

We’re not including the things it does automatically, like regulate your breathing, heartbeat, and so on. But your brain can do those things when you’re asleep.

But you wouldn’t drive a car while asleep, would you?

Scientists have discovered that so-called “multi-tasking” requires a splitting of the brain. Different parts of your brain will be used to do a variety of things. If you eat popcorn while watching TV, part of your brain moves your hand into the bowl, while another part pays attention to what Daryl Dixon is doing to zombie number 62.

But driving is not just holding the wheel straight and watching the road. Your working memory temporarily memorizes where all the other cars are so you can keep a sense of them as they move around you. You’re long-term memory is recalling landmarks and routes for you to follow. You’re hippocampus is filtering out the sound of other cars but still paying attention for the sound of horns and sirens, making sure to send those impulses to your frontal cortex where you can process what to do with them.

So, while you’re checking your phone, you’re checking your phone, and nothing else. You’re wiping your working memory clean (where did the other cars go?), distracting your long-term memory (was that a right here or a left) and confusing your hippocampus (I hear a horn but there’s no horn icon in this text message).

And even nothing bad happens while you’re looking at the phone, when you look up again and disengage autopilot, you’re still not driving—you’re getting a whole new set of data before you’re fully immersed in the act of driving again.

So, go ahead, give yourself an estimate—how long did you glace at that phone? 2 seconds? Now double that, to account for how long it takes for your brain to switch.

A car traveling 55 mph covers 322 feet in 4 seconds. And since it takes a person about second to respond to a sudden change in environment, and since most cars take about 120 feet to come to a stop with a sudden application of the brakes from 55 mph, that all adds up to 600 feet.

Anything that happens less than two football fields away from you when you check your phone is going to be an accident.