Odds are you have heard someone say they’re good at multitasking. Maybe it was a coworker who often answers the phone while sending emails or going over the monthly budget. Maybe it was a study partner in college who liked to text, browse the internet and study two or three subjects simultaneously.

People honestly believe they can multitask. They believe they’re good at it. And they’re all wrong.

The thing is, multitasking is not real. It’s a myth. Yes, everyone believes in it, but your brain can’t do it. No one’s brain can do it. With the exception of automatic functions, you do one thing at a time.

So what is multitasking?

If multitasking isn’t real, what are people doing when they think that’s what they’re doing? The reality is that they’re just switching from one task to another. They do it very quickly and unconsciously. The human brain simply does know how to take on multiple tasks simultaneously. So it does one task, then another, then another, cycling through however many on which you’re trying to focus.

That study partner wasn’t texting and studying. She was texting, then studying, then texting, etc. It’s one or the other in every case. That’s just how the human brain works.

Cognitive distraction

Attempting to multitask leads to serious cognitive distractions behind the wheel. A driver may think he or she is driving and talking on the phone at the same time, but the brain is really just rapidly jumping back and forth between the two, trying to keep the person engaged in the conversation and the car on the road.

So-called multitasking takes a serious toll. One study found that people who use their phones while they drive overlook about half of the environment around them.

What are they missing? Stop signs. Turn signals. Red lights. Traffic shifts. Construction zones. Traffic jams. Pedestrians in the crosswalk. The list is nearly endless and evolving. Every little thing that’s overlooked could lead to a serious accident.

Another study actually found that cellphone use in the car decreased brain activity by 37 percent. Researchers studied parietal lobe activation, which connects to the way your brain interprets and processes moving images. If you’re engaged in a conversation while driving, your awareness decreases by more than a third as your brain tries to accomplish both tasks at once.

Car accidents

The myth of multitasking makes people believe it’s safe. They overlook the cognitive distractions. They think they can drive carefully. When they cause accidents that could have easily been avoided, those who suffer injuries must know all of their options.