So how does all of this multitasking affect our brains?
According to NPR, humans actually can’t multitask—at least, not in the way we think we can.
Earl Miller, a professor of neuroscience at MIT, reports that even when we think we’re focusing on multiple things simultaneously, we’re actually just switching our attention back and forth very rapidly.
Sometimes that’s because two tasks are too similar, such as talking on the phone and doing homework. Both tasks involve speech and language, and the brain experiences too much intereference between them to do both at once.
But even if multitasking the way we usually think of it is impossible, there’s no doubt that humans—especially high-schoolers—frequently attempt to complete multiple tasks at once. We study while listening to music or watching TV; we leave six tabs open on our laptops at all times, available as a respite from our work.
Clifford Nass, a cognitive scientist at Stanford University, tested his students’ cognitive abilities after he saw them multitasking often.
Nass reports that high multitaskers were bad at telling the difference between relevant and irrelevant information and had trouble with mental organization. They also struggled to switch between tasks more than people who were less frequent multitaskers. Nass’s study also found that high multitaskers had more social problems than low multitaskers, which he suggests could be because they don’t pay attention to people well.
Of course, studies like this one have caveats—for instance, people prone to unhappiness or who already have trouble focusing may gravitate toward multitasking.
But adolescent brains are still developing, so chronic multitasking as a teenager and young adult could have lifelong effects on people’s brains. All of this determination to do multiple things at once often manifests in a different, though related, problem: the tendency for teenagers to fill their schedules with extracurriculars, sometimes more than they can handle.
How much is too much? The answer, says child and adolescent psychologist Alvin Rosenfeld in a New York Times article, lies in balance. “Enrichment activities are perfect. They add a lot to kids’ lives. The problem is, we’ve lost the ability to balance them with down time, boring time,” Rosenfeld says.
In the same article, psychologist Michael Thompson adds in another part of the equation: getting enough sleep.
According to the National Sleep Foundation, teenagers need 8.5 to 9.25 hours of sleep every night, and it can be difficult to get that much in combination with extracurriculars, homework and early school starts.
Fairfax County is shifting school start times about 40 minutes later next year, but if after-school activities shift later as well, students still may be struggling to get the recommended amount of sleep.
When it comes to multitasking, the science is still out. Neuroscience is a rapidly changing field, and today’s teenagers are the first generation to grow up with multiple tabs open and a smartphone nearby.
For now, be mindful of your sleep and homework when you make your schedule, and if you can’t devote your full attention to everything you want to get done, consider letting one or two things go. And, of course, stay posted: as scientists become increasingly interested in multitasking and the adolescent brain, you may want to think about your own behavior, or even change it.