Is multitasking a myth? What research says about doing two things at once

Most of us multitask all day. We answer a message during a call, keep an eye on email while writing, or listen to a podcast while sorting files. Some people say they are good at it. Others have heard that multitasking is a myth and that the brain can only do one thing at a time.

The research supports neither slogan exactly. Laboratory studies going back decades show that two demanding tasks almost always interfere with each other, and that people are poor judges of their own multitasking skill. But the same research shows that some combinations of tasks run side by side with little cost, that practice can shrink the interference, and that a widely shared finding about heavy media multitaskers has been hard to replicate.

Short answer: for two tasks that both need decisions, memory or language, true parallel work is limited. What feels like multitasking is usually fast switching, and each switch costs time and accuracy. Easy, well-practised or physical tasks can often be combined. The practical question is not whether you can multitask at all, but which combinations cost you, and by how much.

What counts as multitasking?

Researchers use the word for several different situations, and mixing them up causes most of the confusion. A 2018 review in Psychological Bulletin argued that two lines of research, one on doing two tasks at the same moment and one on switching between tasks in sequence, had developed largely separately, and that both describe the same underlying limits (Koch, Poljac, Müller and Kiesel, 2018).

Type	Everyday example	What usually happens
Dual-tasking: two tasks at the same moment	Typing a reply while listening to a colleague	One task waits for the other at the point where you choose what to do, so at least one slows down or slips
Task switching: alternating quickly	Writing a report and checking chat every few minutes	Each switch adds time while your mind reloads the rules and goals of the other task
Media multitasking: several media streams at once	Watching a video with a phone in hand and a second tab open	Studied mostly through questionnaires about habits; links to attention are debated
Combining an automatic task with a demanding one	Walking while talking, folding laundry while listening to music	Often works well, because one task needs little central control

Our page on context switching covers the sequential case in depth. This article focuses on the simultaneous case and on the claims people make about multitasking ability.

Why two tasks collide: the response bottleneck

One of the most studied findings in attention research is called the psychological refractory period. Give someone two simple tasks in quick succession, such as pressing a key for a tone and saying a word for a picture, and the response to the second task is delayed. The closer together the two tasks come, the longer the delay.

Harold Pashler's influential 1994 review concluded that this delay reflects a stubborn bottleneck in the process of choosing actions, and probably in memory retrieval more generally. Seeing and hearing can proceed in parallel, but deciding what to do tends to happen one task at a time. Other limits linked to preparing a task, perception and timing add their own forms of interference (Pashler, 1994).

That is why the most demanding combinations feel so hard. Writing an email while following a meeting requires language, memory and decisions from both tasks at once. One of them has to wait, even if the wait is too short to notice.

The cost of switching

When people try to do two complex tasks, they usually alternate. Joshua Rubinstein, David Meyer and Jeffrey Evans ran four experiments in which people either repeated one task or alternated between two, using shape classification rules and arithmetic problems. Alternating produced a reliable time cost. The cost grew when the rules were more complex and shrank when a clear cue showed which task came next. Switching into an unfamiliar task took longer than switching into a familiar one (Rubinstein, Meyer and Evans, 2001).

The authors proposed two stages for each switch: shifting the goal, then activating the rules of the new task. In their experiments the costs were fractions of a second per switch. Many popular articles turn these results into a single large figure, such as a claim that multitasking costs 40% of your productivity. That figure circulates widely, but it does not appear in the abstract of this study, and we could not trace it to a primary source we were able to read, so we do not repeat it as a finding.

What the experiments do show is that every switch costs something, that complex tasks cost more and that the costs add up when switches are frequent. Our article on attention residue covers a related effect: part of your attention can stay on the previous task after you move on.

Can practice make multitasking work?

The bottleneck is not as fixed as it first looked. In three experiments, Eric Schumacher and colleagues found that after relatively modest amounts of practice, at least some participants achieved what the authors called virtually perfect time sharing on two basic choice reaction tasks. The amount of interference also depended on instructions about which task had priority, and on whether people preferred to do the tasks together or one after the other (Schumacher and colleagues, 2001).

A later review by Rico Fischer and Franziska Plessow argued that asking whether people process tasks only in parallel or only in sequence is too simple. People shift between more parallel and more serial processing depending on the conditions, and the authors defined efficient multitasking as the ability to make that shift flexibly as demands change (Fischer and Plessow, 2015, full text).

Two limits are worth keeping in mind. These studies used simple laboratory tasks, such as pressing keys in response to tones and shapes, practised many times. And practice helps most when a task becomes routine. Writing, reading and problem solving stay demanding however often you do them, so they are the least likely to run alongside another demanding task without a cost.

Are some people supertaskers?

In a 2010 study, Jason Watson and David Strayer tested 200 people in a high-fidelity driving simulator. Participants drove, completed a demanding auditory version of a working memory task called the operation span task, and then did both at once. The vast majority performed significantly worse when combining the two. But 2.5% of the sample, five people, showed no drop at all, and they also scored in the top quarter on the single tasks. The authors called them supertaskers and reported that this was more than would be expected by chance (Watson and Strayer, 2010).

The study is often cited as proof that some people can multitask. It is better read the other way: in this sample, about 97 in every 100 people paid a measurable price. A small group of exceptional performers does not make multitasking a safe bet for anyone who has not been tested, and the original group was small.

People overrate their own skill

The more striking result concerns who chooses to multitask. In a study of University of Utah students, Sanbonmatsu and colleagues measured how much people multitask, how good they thought they were at it and how they actually performed on a demanding memory task used as a measure of multitasking ability. The people who multitasked most were not the most capable. Self-reported media multitasking and phone use while driving were negatively correlated with actual ability, and perceived ability was significantly inflated. People with less executive control and higher impulsivity reported more multitasking, which the authors suggested may reflect difficulty blocking out distractions (Sanbonmatsu and colleagues, 2013, full text).

A 2025 study of 611 undergraduates found a similar gap. Students who overestimated their multitasking ability, relative to their own task-switching performance and to other people, felt more confident about texting while driving and did it more, as measured by both questionnaires and phone app data. Their actual multitasking ability was not related to how often they did it (Bowman-Callaway, Schulte and Payne, 2025).

Both studies used student samples, and correlations cannot show cause and effect. But together they suggest that feeling good at multitasking is a weak guide to whether you are.

Does heavy media multitasking change your attention?

A 2009 Stanford study made headlines with a surprising result. Eyal Ophir, Clifford Nass and Anthony Wagner built a questionnaire to classify people as heavy or light media multitaskers and compared the groups on standard attention tests. Heavy media multitaskers were more affected by irrelevant items in what they saw and in memory, and they were slower at switching between tasks, possibly because they were less able to filter out the task they were not doing (Ophir, Nass and Wagner, 2009, full text).

Many articles still present this as settled. The follow-up research is less clear.

• Replications were mixed. Wisnu Wiradhany and Mark Nieuwenstein ran two replication studies with 14 tests. Only five showed the expected pattern, and only two held up in a more conservative Bayesian analysis. Their meta-analysis of 39 effect sizes found a weak association between media multitasking and distractibility that became non-significant after correcting for small-study effects. They concluded that they questioned whether the association exists in laboratory tasks (Wiradhany and Nieuwenstein, 2017, full text). A published correction to the paper concerns the reported number of participants in their first study.
• A review by the original lab was more cautious than the headlines. Melina Uncapher and Anthony Wagner wrote in 2018 that the literature was still sparse and mixed. On balance, heavier media multitaskers did worse in several areas, although many studies found no difference. Where differences appeared, they were often on tasks that depend on sustained attention. The direction of causality is unknown (Uncapher and Wagner, 2018, full text).
• Attention lapses may be the link. In a 2020 study of 80 young adults, Kevin Madore and colleagues recorded EEG and pupil size during a memory task. Signs of attention lapsing just before people tried to remember, including posterior alpha power, were associated with forgetting. People who reported heavier media multitasking were more prone to attention lapses, and those lapses partly accounted for the link between media multitasking and memory (Madore and colleagues, 2020, full text).

The fair reading is that heavy media multitasking is associated with somewhat weaker sustained attention in some studies, not that it has been shown to damage the brain. It is just as plausible that people whose attention already wanders more are drawn to more media at once. If your mind often drifts during long tasks, our page on mind wandering explains what is normal.

When multitasking is fine, and when it costs you

Putting these findings together gives a simple rule of thumb: combinations go well when at most one task needs your decisions and language at any moment.

Usually workable	Usually costly
Walking while talking or thinking	Writing while following a conversation
Routine physical chores with music or a podcast	Reading or studying with messages arriving
Background music during routine, repetitive work, for many people	Two pieces of problem solving at once, such as a spreadsheet and a call
A practised, simple task alongside a familiar one	Anything new, complex or high stakes, including driving while using a phone

Music is a common grey area. Our article on whether music helps you focus covers when it helps and when lyrics compete with reading and writing.

What to do instead

If most of your multitasking is really rapid switching, the goal is fewer, cleaner switches rather than a ban on doing two things at once.

• Give demanding work a single lane. Close chat and email for a set block, and reopen them at a planned time. Our guides to time blocking and deep work show how to structure those blocks.
• Batch the small stuff. Handle similar shallow tasks together so you switch rules less often. See task batching.
• Make switches cheaper. Rubinstein's experiments found that clear cues reduced switch costs. Before you leave a task, write one line about where you stopped and what comes next.
• Pre-decide your response to interruptions. An if-then plan such as "If a message arrives during a writing block, then I will note it and keep writing" removes a decision in the moment. Our article on implementation intentions covers what the evidence shows.
• Pair automatic tasks on purpose. Walking meetings, chores with audio and other easy pairings are fine. Save your full attention for the tasks that need it.
• Watch for overload. If you are juggling more than you can track, the problem may be load rather than technique. Our page on cognitive overload explains the signs.

A one-week test

Because people are poor judges of their own multitasking, test it rather than trusting how it feels.

• Pick one recurring task that takes 30 to 60 minutes and has a clear output, such as drafting a section, clearing a set of reviews or writing code for one ticket.
• On alternate days, do it two ways: once with chat, email and phone open as usual, and once with them closed until the task is done.
• Record three things each time: how long it took, how many errors or fixes you made afterwards, and how often you switched away.
• Compare after a week. If the single-task days were faster or cleaner, that is your personal answer, whatever you felt at the time. For a separate snapshot of sustained attention, try our attention span test.

Where Zone fits

Zone is a pair of EEG earbuds with an app that shows app brain states, such as Locked In, In Flow, Drifting, Running Hot and Depleted. The earbuds read signals through an in-ear EEG array, explained in our article on in-ear EEG. If you wear Zone during the one-week test, you can set your session summaries from single-task days beside those from multitasking days, for example to see how long the app showed Locked In, or how often it showed Drifting. Our guide to focus tracking explains more. Treat these as app estimates, not a measure of attention lapses or of multitasking ability, and keep your timings, error counts and finished work as the main evidence. Zone does not diagnose, treat, or manage any medical condition.

Common questions

Is multitasking a myth?

Partly. For two demanding tasks, people mostly switch rather than work in parallel, and both tasks suffer. But easy or automatic tasks can often be combined, and practice can reduce interference on simple tasks.

Can the human brain really multitask?

It can process some information in parallel, such as sights and sounds, but choosing what to do tends to happen one task at a time. That limit, studied as the psychological refractory period, is why demanding tasks collide.

Are some people good at multitasking?

A small minority may be. In one driving simulator study, 2.5% of 200 people showed no cost from adding a demanding second task. Most people performed worse, and people who multitask the most tend to overrate their ability.

Is multitasking bad for your brain?

There is no good evidence that multitasking damages the brain. Some studies link heavy media multitasking to weaker sustained attention and more attention lapses, but the findings are mixed and cause and effect are unclear.

What is the difference between multitasking and task switching?

Multitasking usually means trying to do two things at once. Task switching means alternating between them. In practice, most everyday multitasking with demanding tasks is fast task switching, and each switch has a cost.

Is multitasking a skill worth listing on a resume?

Employers often mean the ability to manage several responsibilities over a day, which is a real skill. That is different from doing two demanding tasks at the same moment. Planning, prioritising and switching cleanly are more accurate ways to describe it.

Sources

1. Koch, I., Poljac, E., Müller, H., and Kiesel, A. (2018). Cognitive structure, flexibility, and plasticity in human multitasking: an integrative review of dual-task and task-switching research. Psychological Bulletin, 144(6), 557 to 583. doi.org/10.1037/bul0000144
2. Pashler, H. (1994). Dual-task interference in simple tasks: data and theory. Psychological Bulletin, 116(2), 220 to 244. PubMed record
3. Rubinstein, J. S., Meyer, D. E., and Evans, J. E. (2001). Executive control of cognitive processes in task switching. Journal of Experimental Psychology: Human Perception and Performance, 27(4), 763 to 797. PubMed record
4. Schumacher, E. H., Seymour, T. L., Glass, J. M., Fencsik, D. E., Lauber, E. J., Kieras, D. E., and Meyer, D. E. (2001). Virtually perfect time sharing in dual-task performance: uncorking the central cognitive bottleneck. Psychological Science, 12(2), 101 to 108. PubMed record
5. Fischer, R., and Plessow, F. (2015). Efficient multitasking: parallel versus serial processing of multiple tasks. Frontiers in Psychology, 6, 1366. PubMed record, full text
6. Watson, J. M., and Strayer, D. L. (2010). Supertaskers: profiles in extraordinary multitasking ability. Psychonomic Bulletin and Review, 17(4), 479 to 485. PubMed record
7. Sanbonmatsu, D. M., Strayer, D. L., Medeiros-Ward, N., and Watson, J. M. (2013). Who multi-tasks and why? Multi-tasking ability, perceived multi-tasking ability, impulsivity, and sensation seeking. PLoS One, 8(1), e54402. PubMed record, full text
8. Bowman-Callaway, C. E., Schulte, B. D., and Payne, S. C. (2025). Perceived vs. actual multitasking abilities: predicting texting while driving efficacy and behavior from overconfidence. Accident Analysis and Prevention, 217, 108058. PubMed record
9. Ophir, E., Nass, C., and Wagner, A. D. (2009). Cognitive control in media multitaskers. Proceedings of the National Academy of Sciences, 106(37), 15583 to 15587. PubMed record, full text
10. Wiradhany, W., and Nieuwenstein, M. R. (2017). Cognitive control in media multitaskers: two replication studies and a meta-analysis. Attention, Perception, and Psychophysics, 79(8), 2620 to 2641. PubMed record, full text. Correction: PubMed record
11. Uncapher, M. R., and Wagner, A. D. (2018). Minds and brains of media multitaskers: current findings and future directions. Proceedings of the National Academy of Sciences, 115(40), 9889 to 9896. PubMed record, full text
12. Madore, K. P., Khazenzon, A. M., Backes, C. W., Jiang, J., Uncapher, M. R., Norcia, A. M., and Wagner, A. D. (2020). Memory failure predicted by attention lapsing and media multitasking. Nature, 587(7832), 87 to 91. PubMed record, full text