Contrary to what most people think, most humans are atrocious at multi-tasking.
In fact, only about 2% of the population can excel on more than one task at the same time, according to research by David Strayer, a psychology professor at the University of Utah. The rest of us get worse at things when we try to do more than one thing at once.
There's hope though — at least some. Psychology researchers have found that people can improve their multitasking abilities, and a recent study published in the journal Proceedings of the National Academy of Sciences pinpoints at least part of how that looks in the brain.
Researchers at The University of Queensland in Australia wanted to see specifically if people could get better at multitasking with training. If so, the researchers would use brain imaging technology to examine how those study participants' brains changed along the way.
They selected 100 people for the study — a good number for research involving brain imaging — and set them to doing two tasks: pushing a button when the right one of two shapes flashed on a screen and when they heard one of two sounds. Those aren't tasks we juggle in real life, of course, but are common in such studies.
Researchers first had study participants familiarize themselves with the tasks. They then had participants do the tasks one a time and then try to complete them simultaneously while scanning their brains with an MRI machine.
As you might imagine, people took longer and made more errors while trying to do both tasks at the same time.
Then they split the group in half. The training group did multitasking training sessions over the next three days, while the control group did another sort of training focused on visual ability to search for something. (The researchers didn't want a "motivation gap," where the control group basically knows they are supposed to perform worse, so they had them do some sort of training).
After three days, both groups took the test again while having their brains scanned. Both groups performed better than they had the first time, but the group who'd received multitasking training improved speed and accuracy significantly more while multitasking than the control group.
The training was nothing special — essentially practicing each task by itself and then at the same time — and yet it worked, suggesting that practicing multitasking may actually make people better at it.
What was happening in the brain?
Researchers focused their attention on the frontoparietal and subcortical (FP-SC) brain regions, since these areas are known to be important for performing multiple tasks.
In the study, they write that the main hypothesis for how multitasking training works has typically been that the FP-SC stops being involved when a person has received training for a task. This is not what they found.
Instead, they found that the tasks seemed to trigger more specific areas of the FP-SC regions after training. These areas were still where information was being processed, but it was processed in more specific and — they think — efficient ways. In the study, they write that this suggests "training refines the neural code that contributes to task performance."
So we've learned not only that people can improve at multi-tasking, but that specifically we can improve the parts of our brain that are connected to helping us multitask.
But there are still caveats here. The participants in this study had to do each task — blinking shape, sound, and both together — a mind-numbing 1,008 times, which is quite a lot of practice. We also don't know that training improves all types of multitasking or what the limits of that training might be. These tasks involved a specific type of activity, but the brain regions involved in other, more complex activities (like walking and texting simultaneously, or responding to emails while writing a report) might be totally different and impossible to improve.
If there's a part of your life that continuously trains you to handle two tasks simultaneously, this work indicates that you at least have a shot at getting better at it. Just remember that even if your multitasking performance can be improved, you'll still be more efficient if you try to focus on just one task at a time.