Multi-tasking: Sorry, you can't do more than two things at once

[BlueRidge]

So says a new study of the brain:

Why We Can't Do 3 Things at Once (LiveScience)

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 Universite Pierre et Marie Curie in Paris, France. "However, we cannot multitask with more than two tasks."

Do you think you can do more than two things at once? Or do you try to even though you can't?

The results might also explain why humans seem to have a hard time making decisions between more than two things, Koechlin said.


Previous work has indicated that people like binary choices, or decisions between two things. They have difficultly when decisions involve more than two choices, Koechlin said. When faced with three or more choices, subjects don't appear to evaluate them rationally; they simply start discarding choices until they get back to a binary choice.

and then there are those of us that have trouble making choices at all...

[*Jen*]

I call BS on the choices thing. Discarding options until it comes down to 2 is still making choices. If you have 2, you reject one of the options. That's just how it workls.

As for multi-tasking...I'm fairly sure I can do more than 2 things at once

[BlueRidge]

...As for multi-tasking...I'm fairly sure I can do more than 2 things at once

Hopefully, one of them is not driving...

[Evilynn]

How do they define "things"? I can layer belly dance movements on top of one another and still play the zills. Or is "dancing" (nevermind how many movements is layered on one another) considered one thing and playing the zills another? Or are "things" only things you have to put more of a conscious mental effort into?

[*Jen*]

Hopefully, one of them is not driving...

Nope. Apart from the fact I don't have a car, I was taught to drive by my father who, as a sixteen year old, survived an accident which killed his own father.

I didn't even listen to the radio for years after I got my licence because he was such a driving Nazi

[MOIJTO]

Really?

I have no trouble making decisions at all, its quite easy when you know your priorities.

I can do far more than 2 things at once, its a mandatory requirement of women!

I could never understand what "multi-tasking" was some, psuedo-pyscho babble.

I just stay busy....very very busy!

[susan6]

How do they define "things"? I can layer belly dance movements on top of one another and still play the zills. Or is "dancing" (nevermind how many movements is layered on one another) considered one thing and playing the zills another? Or are "things" only things you have to put more of a conscious mental effort into?

Dancing while playing the zills and balancing a sword on my head is also do-able. I call BS on this study.

[*Jen*]

Well it was written by a man. And it's a well known fact that men can't multi-task

[BlueRidge]

I haven't had a chance to read the whole original report, but I'm guessing that "can't do" is too strong a conclusion, more that the study shows that the brain is set up to easily divide up two tasks, and more than two are considerably more difficult and therefore done less effectively.

Here's the concluding paragraph from the study:

Moreover, the two frontal lobes, which jointly drive the pursuit of a single goal, divide for driving concurrently the pursuit of two independent goals. This finding suggests that the human frontal function is limited to accurately driving the pursuit of two concurrent goals at one time. Consistent with the previously suggested inability of frontopolar function to recursively compute cognitive branching (4), this capacity limit places a severe constraint bearing upon human higher cognition and may clarify several limitations in human decision-making and reasoning abilities (4). However, no functional dichotomies were observed in the lateral prefrontal and frontopolar cortex despite their involvement in dual-task performance, indicating that these regions in both hemispheres jointly control the serial execution of tasks rather than processing them independently. The lateral prefrontal and frontopolar cortex thus appear to maintain the integrity of volition, at least in healthy human brains.

Divided Representation of Concurrent Goals in the Human Frontal Lobes
(full text available by subscription only)

[Prancer]

Dancing while playing the zills and balancing a sword on my head is also do-able. I call BS on this study.

I don't think that would be considered doing three things, though, because while you are doing three different things, they are three things that comprise one whole. IOW, you are performing three related tasks with a single goal.

What they are talking about, I think, is doing three distinctly different things that have different purposes. For example, cooking and talking on the phone, the two-task sample given, is not the same as, say, cooking three different dishes at the same time for dinner.

I think a better example of multitasking three things at once would be something like--can you balance your checkbook, watch TV and talk on the phone at the same time?

[BlueRidge]

The study uses the word "goals" so I'm actually thinking they are talking about trying to achieve two or more goals at once--with each goal require doing a number of things at once--such as the dancing activity might, as Prancer notes there reading all of Prancer's post and thinking at the same time was too many things at once for me...

[Evilynn]

What they are talking about, I think, is doing three distinctly different things that have different purposes. For example, cooking and talking on the phone, the two-task sample given, is not the same as, say, cooking three different dishes at the same time for dinner.

I'd call that 3 serialized tasks though, it's hard to stir 3 pots at once, unless you're very good with your feet. With the dancing you are doing the different things simultaneously, it's like patting your head and rubbing your belly at the same time (while balancing a sword and playing the zills, if you had hands enough), it definitely takes a lot of practice, but it's doable.

I think a better example of multitasking three things at once would be something like--can you balance your checkbook, watch TV and talk on the phone at the same time?

That's probably what they meant by "things", something you need active reasoning to accomplish (the article mentions sorting lists). With practice I think you could, but it'd probably be a sub-optimization. I read an article on a study of something similar not too long ago.

[BlueRidge]

can you balance your checkbook, watch TV and talk on the phone at the same time?

Seriously, I can't do any two of those things at the same time. I wonder what images of my brain would show...

If you can pursue two goals at once, then shouldn't you be able to talk on the phone and drive at the same time?

[gkelly]

If you can pursue two goals at once, then shouldn't you be able to talk on the phone and drive at the same time?

Well, it is possible to talk on the phone and execute routine driving at the same time.

The problem is that it's not possible to talk on the phone and respond effectively to an emergency driving situation, or even a small unexpected change in the driving routine, at the same time.

And because conditions in traffic are constantly changing unexpectedly, and it's possible for a driving emergency to arise at any time without warning, it's not a good idea to be doing something else at the time that would distract you from noticing or responding immediately and fully.

[TalentedButHumble]

Here's the concluding paragraph from the study:

Wow, I can't even wade throught that 'graph if it's the only thing I do.

[Nan]

And it's a well known fact that men can't multi-task

They do have to put down their beer can to use the TV remote, don't they?

j/k

[mpal2]

I think a better example of multitasking three things at once would be something like--can you balance your checkbook, watch TV and talk on the phone at the same time?

Yes. You balance the check book during commercials.

Seriously though, I could talk to the friend and balance the checkbook but would only be able to give you a high level summary of the tv show. If I was watching the show at a detailed level and balancing the check book it would impact the conversation with the friend (unless we were watching the show and talking about it).

I don't know that I would put the limit at 2 activities or 3. I would say the number of things we multi-task would be limited by how much detail we need to have included in the task. The more complex it becomes the less likely we are to multi-task. If some activities become an auto-pilot function over time, something that used to be harder to multi-task would get easier.

Simple autopilot example:

When I first moved into my house I had to concentrate on vacuuming around the furniture. Now I know the reach and the angles and do a million other things as I'm zooming through the house.

[Japanfan]

Yes. You balance the check book during commercials.

In which case you would be looking at the checkbook and doing the numbers - you could hear what was being said on the commercial at the same time, but if you got on the phone with someone you would probably have to tune out the commercial to listen and talk to them.

It's possible to listen to multiple sounds at one time but the more complex the sounds, the harder it becomes. I doubt you could hear and process every word said on a TV while simultaneously hearing and process what someone was saying to you on person or in the phone. You have to tune out the one to pay attention to the other.

I think what the article says about two things at a time is probably true. Very often what is considered multi-tasking is actually moving between a number of separate tasks done serially.

I can talk on the phone, do something on the computer, and give my dog the hand signal for sit or chuck a ball in the air. But I have to stop typing if I am going to give a signal or chuck a ball, so at that moment, I'm only really doing two things, not three.

But I do think people can choose between more than two things and do so on a regular basis. If anything two is often harder, because you may have narrowed down two things that you want/like the most.

[JJH]

I'm just trying to master doing one thing at once.

[AYS]

I definitely multitask on >2 things frequently (particularly during the GP season )

That being said, I'm a nervous frakkin wreck, so uh, there's that side of things to take into account.