Research Suggests Brain Has a 2-Task Limit for Multitasking

suraj.sun writes with a story from LiveScience about just how much attention you can devote to each of the tasks on hand that scream for it: "The brain is set up to manage two tasks, but not more, a new study suggests. That's because, when faced with two tasks, a part of the brain known as the medial prefrontal cortex (MFC) divides so that half of the region focuses on one task and the other half on the other task. This division of labor allows a person to keep track of two tasks pretty readily, but if you throw in a third, things get a bit muddled. 'What really the results show is that we can readily divide tasking. We can cook, and at the same time talk on the phone, and switch back and forth between these two activities,' said study researcher Etienne Koechlin of the Université Pierre et Marie Curie in Paris, France. 'However, we cannot multitask with more than two tasks.'"

Comments

what is a single task to the brain?

[slashmojo]

Is talking on the phone really a single task? Is cooking? Surely each of those is made up of countless sub-tasks even if you don't consciously think about them.

Re:what is a single task to the brain?

[Pharmboy]

Is talking on the phone really a single task? Is cooking? Surely each of those is made up of countless sub-tasks even if you don't consciously think about them.

If you were just saying random words, then perhaps not. But if you are discussing the new project at work, or what little Johnny did at school, or even about sports, it requires pulling in previous experiences, remembering specific events, drawing conclusions, etc., which are "subroutines" in a single task, communicating. A phone conversation can actually take more brain power than driving down the highway. Think about it, when someone is driving and talking on the phone, it is obvious that the cell phone requires more attention than driving. As for being sub-tasks, all tasks are generally linear subtasks that would qualify as a single task.

Perhaps that is why people tend to stray into the other lane when driving/talking on the cell. A third activity comes in or they have to fork a thought for consideration during the conversation, and they run out of brainpower/memory, so the least important activity (driving) gets swapped out for a second. Humans just need more RAM.

How about that, a computer analog for a car problem, instead of the other way around!

Re:what is a single task to the brain?

[UpnAtom]

Especially in men, right brains don't talk. So that's exclusively left-brain.

Driving (at least the direction & speed control) is right brain. The time it's most likely to engage your left brain is when you have to consciously think ie planning your route, adapting to unusual road conditions. Apart from that driving & talking is fairly easy for experienced drivers. Typically, drivers talk in a monotonous voice as inflection is right hemisphere.

Try adding a column of figures eg restaurant bill and having a conversation at the same time - pretty damn hard because both are left brain. So there we're only single-tasking.

I think what this research shows is that we use both sides of our brain when we're single-tasking. Some areas of the brain are very specialised but other areas can be trained to perform similar functions (for some people, the right hemisphere spelling a word would be an unnatural task). If we're doing two tasks for which different hemispheres of the brain can assigned one of the tasks, then the brain is quite adept at dividing up the workload.

Please define task

[houghi]

I can eat, breath, type and read at the same time while listening to music.
At these moments I am also thinking ahead of what I am going to do.

Even typing could be considered doing several tasks at the same time. The sample of 'cooking' in the summery can be defined as multiple tasks. You are standing, you are tasting and smelling, you are planning of what to do next and probably stirring as well as looking.

For a chef in a kitchen, cooking is also interacting with other people at the same time.
For some people cooking is pressing the button on the microwave and waiting for the 'ting' of the machine.

So what is a 'task'?

Re:I used to work on the road...

[lattyware]

Not having an accident doesn't make it safe.

Pick two

[characterZer0]

Thinking
Talking
Listening

Pick two.

Re:Pick two

[IANAAC]

If you are an interpreter, you routinely do all three at the same time.

Sorry, just because it's difficult for some doesn't mean it's impossible. It does take training and practice, though.

Practice

[TheLink]

Seriously though, you might be able to learn how to do that if you could practice doing that 100 times every day, for a month under safe simulated conditions (e.g. driving simulator, and simulated eating too, otherwise you'd end up killing yourself by overeating ;) ).

It's all about practice. Practice, practice, practice.

The first time you drive a car (especially a manual), there are so many tasks.

After a while of practice, your brain configures itself to automatically make those tasks into a subtask, and groups them all into one task - "driving".

Of course some people may never be able to do it. But I think a high proportion of people can. And I bet there are some people who can learn to do it after very short time - just like some people can learn to juggle very quickly, and there was that recent article about supertaskers.

I'm sure Michael Schumacher can eat breakfast and type on a cellphone and still do F1 laps faster than I can, when I'm just doing F1 laps (just driving, not eating or doing other stuff).

The trouble with most people is they're trying to do "for real" without practicing _properly_. That's like trying to juggle chainsaws, without learning how to juggle balls first, and then gradually working your way up under controlled conditions.

The type of task matters

[Webz]

In my opinion, the type of task matters. And I think it has to do with what parts of your brain are used. For example, I can code/refactor and listen to a podcast just fine simultaneously. But if it's two comprehension-based tasks, like reading AND listening, I can't do them. Or lately I've even noticed I can't mentally elaborate on a thought and listen to a podcast at the same time.

The coding and listening thing seems very left brain/right brain to me.

Also, to the poster that mentioned musical multi-tasking... That's really interesting! But I think it helps that we as musicians have been training since a very young age to accept that level of multi-tasking, so the things that become muscle memory do. Fingering, breathing, sight reading, etc. Really the only thing that matters by show time is watching the conductor, the rest should be on semi auto pilot.