Multitasking is the new norm. In the modern world of smartphones and continuous internet access, information and distractions are all around us. I never manage to write a full article or work on a project without regularly drifting toward WhatsApp, Twitter, and the news. Even when I’m not drifting toward distractions, I am always listening to music while I work. My excuse is that music helps to drown out distractions, and helps to put me in a more focused mental state. But if I’m honest, my singing and head-nodding breaks suggest that music acts as a frequent distraction too.
The truth about multitasking is that it’s not really multitasking at all. The attention processes in our brains aren’t built to simultaneously focus on several streams of information across different tasks. Instead, we shift between individual tasks that require our attention. Some people can do this fast enough that it looks like true multitasking — just watch professional gamers battle each other in demanding computer games — but when multiple tasks require focused attention, you’re never really engaging all of them at the same time.
This is why learning to drive a car is so difficult. When you’re learning, you need to pay careful attention to the several things you need to do: steering, checking mirrors, shifting gears, managing foot pedals, etc. You need to switch your attention between the tasks quickly and effectively to drive safely. But when you’re an expert, each of the tasks becomes habitual and requires less attention. So you can focus your mind on watching the road while everything else pretty much runs itself. You go from “multitasking” to single-tasking.
Rather than tackling the technicalities of what multitasking means in the brain, one group of researchers wanted to test how beliefs in multitasking affect performance. Most people think they’re great multitaskers: 93.32% of Americans in a survey believed they multitasked as well as, or better than, the average person. A large number of those people in the survey must be wrong, but perhaps their beliefs are good for them.
In their first experiment, the researchers recruited 162 participants and asked them to transcribe an educational video while watching it. The instructions for each participant were slightly different depending on which of two groups they randomly fell into. The first group was labelled the multitasking group, and participants were asked to complete two tasks at the same time: 1) learning the video content, 2) transcribing the video content. The second group was labelled the single-tasking group, and participants were instead asked to complete the single task of learning and transcribing the video content. In other words, all participants took part in exactly the same task, but only half of them were told that it would require multitasking.
Purely through this difference in perceptions and beliefs, the results between the groups diverged. The multitasking group outperformed the single-tasking group by accurately transcribing significantly more words (224 words vs 177 words on average). They also performed better in a pop quiz that tested knowledge of the video, after the transcribing part of the experiment ended. And these performance benefits emerged even though the two groups spent the same amount of time watching and transcribing the videos.
In a second experiment, rather than manipulating people’s perceptions, the researchers decided to look for possible effects of naturally occurring differences in participant perceptions. They asked 80 participants to complete two word puzzles presented side by side on a screen. The first puzzle was a simple word search while the other was an anagram task in which participants had to create as many words as possible out of a 10-letter string. After the puzzles, participants were asked how much they felt they were multitasking during their efforts. Stronger feelings of multitasking correlated positively with the number of correct words found.
To extend this word puzzle experiment, the researchers took a new set of participants and repeated their manipulations of multitasking perceptions from the first experiment. But this time, the researchers were slightly more subtle in their language. They told the people randomly assigned to the multitasking group that the two word puzzles came from separate studies, while telling the single-tasking participants that the puzzles came from the same study. Once again, the multitasking group performed better than the single-tasking group, finding significantly more correct words in the puzzles (13.65 words vs 7.5 words on average).
With the attentive diligence that marks any good scientist, the researchers repeated the word puzzle experiment a final time after manipulating perceptions, but this time included eye-tracking technology that allowed them to measure how much participants’ pupils dilated during the task. Pupil dilation is linked to greater mental effort, attention, and arousal, so if multitasking believers actually engaged better with the task, you would expect to see their pupils grow larger than the pupils of single-tasking believers.
In line with these predictions, participants in the multitasking group not only repeated their superior performance in the word puzzles, but also showed larger pupil dilation than the single-tasking group. You might think the larger pupils were due to the exciting arousal associated with performing better, but in fact, their pupils were already larger before they even found their first word. The larger dilation then continued throughout the rest of the task. Multitaskers’ brains and bodies physiologically engaged more deeply with the task as soon as participants were attempting the puzzles.
Amazingly, the researchers ran a total of 30 experiments focused on the question of how multitasking perceptions directly improve performance. So the last flick of their wand was to combine the data from all of these studies and understand the strength of the overall effect with a meta-analysis. They measured the magnitude of the difference between the multitasking and single-tasking groups in each study (the effect size), and then calculated the average effect size across the studies with a statistical model that took into account the size of each study. The overall effect was significant and moderate in magnitude, so a belief in multitasking meaningfully and consistently enhanced performance.
It’s always astonishing to find out how powerful our beliefs and perceptions really are. Everything from placebo effects to superstitions can dramatically influence our behavior and its outcomes. We can call it the power of faith and confidence. Thinking positive thoughts is not just a cheap trick that fools you into believing everything is going well; sometimes, things really do go better when you are optimistic. It’s not a supernatural energy or force at work, it’s simply your beliefs and perceptions improving how you approach and deal with a problem.
When it comes to multitasking, the idea that we can do several things at once may be technically incorrect. However, the belief that we are multitasking is enough to make us single-task more efficiently. So this may be a rare situation that calls for feelings over facts. Multitasking might be wrong, but it works.