My brain can multitask even if yours makes a category error

Do not mind the brain, it is just doing its jobs

Keith S. Taber


Can Prof. Dux's brain really not multitask?

I was listening to a podcast where Professor Paul Dux of the University of Queensland said something that seemed to me to be clearly incorrect – even though I think I fully appreciated his point.

"why the brain can't multitask is still very much a topic of considerable debate"

Prof. Paul Dux
Is it true that brains cannot multitask? I think mine can. (Image by Gerd Altmann from Pixabay

The podcast was an episode of the ABC radio programme All in the Mind (not to be confused with the BBC radio programme All in the Mind, of course) entitled 'Misadventures in multitasking'

"All in the Mind is an exploration of the mental: the mind, brain and behaviour — everything from addiction to artificial intelligence." An ABC radio programme and podcast.

The argument against multitasking

Now mutlitasking is doing several things at once – such as perhaps having a phone conversation whilst reading an unrelated email. Some aspects of the modern world seem to encourage this – such as being queued on the telephone (as when I was kept on hold for over an hour waiting to get an appointment at my doctor's surgery – I was not going to just sit by the phone in the hope I would eventually get to the top of the queue). Similarly 'notifications' that seek to distract us from what we are doing on the computer, as if anything that arrives is likely to be important enough for us to need immediate alerting, add little to the sum of human happiness.1

Now I have heard the argument against multitasking before. The key is attention. We may think we are doing several things at once, but instead of focusing on one activity, completing, it, then shifting to another, what multitaskers actually do is continuously interrupt their focus on one activity to refocus attention on the another. The working memory has limited capacity (this surely is what limits our ability to reflectively multitask?), and we can only actually focus on one activity at a time, so multitasking is a con – we may think we are being more productive but we are not.

Now, people do tire, and after, say 45 minutes at one task it may be more effective to break, do something unrelated, and come back to your work fresh. If you are writing, and you break, and take the washing out of the machine and hang it up to dry, and make a cup of tea, and then come back to your writing fifteen or twenty minutes later, this is likely to be ultimately more productive than just ploughing on. You have been busy, not just resting, but a very different kind of activity, and your mind (hopefully) is refreshed. If you have been at your desk for 90 minutes without a break, then go for a walk, or even a quick lie down.

That however, is very different from doing your writing, as you check your email inbox, and keep an eye on a social media feed, and shop online. You can only really do one of those things at a time and if you try to multitask you are likely to quickly tire, and make mistakes as you keep interrupting your flow of concentration. (So, if you have been doing your writing, and you feel the need to do something else, give yourself a definite period of time to completely change activity, and then return fully committed to the writing.)

Now, I find that line of argument very convincing and in keeping my with own experience. (Which is not to say I always follow my own advice, of course.) Yet, I still thought Prof. Dux was wrong. And, indeed, there is one sense in which I would like to think deliberate reflective multitasking is not counterproductive.

If your brain cannot multitask you'd perhaps better hope it focuses on breathing

The brain is complex…

This is a short extract from the programme,

Paul Dux: Why the brain can't multitask is still very much a topic of considerable debate because we have these billions of neurons, trillions of synaptic connections, so why can't we do two simple things at once?

Sana Qadar: This is Professor Paul Dux, he's a psychologist and neuroscientist at the University of Queensland. He takes us deeper into what's going on in the brain.

Paul Dux: A lot of people would say it's because we have these capacities for attention. The brain regions that are involved in things like attention are our lateral prefrontal cortex. You have these populations of neurons that respond to lots of different tasks and multiple demands. That of course on one hand could be quite beneficial because it means that we are able to learn things quickly and can generalise quickly, but maybe the cost of that is that if we are doing two things at once in close temporal proximity, they try to draw on the same populations of neurons, and as a result leads to interference. And so that's why we get multitasking costs.

Sana Qadar: Right, so that's why if you are doing dishes while chatting to a friend, a dish might end up in the fridge rather than the cupboard where it's supposed to go.

Paul Dux: That's right, exactly.

Paul Dux talking to Sana Qadar who introduces 'All in the mind'

Now I imagine that Prof. Dux is an expert, and he certainly seemed authoritative. Yet, I sensed a kind of concept-creep, that led to a category error, here.

A category error

A category error is where something is thought of or discussed as though a member of an inappropriate class or category. A common example might be gender and sex. At one time it was widely assumed that gender (feminine-masculine) was directly correlated to biological sex (female-male) so terms were interchangeable. It is common to see studies in the literature which have looked for 'sex differences' when it seems likely that the researchers have collected no data on biological sex.

Models that suggest that the 'particles' (molecules, ions, atom) in a solid are touching encourage category errors among learners: that such quanticles are like tiny marbles that have a definite surface and diameter. This leads to questions such as whether on expansion the particles get larger or just further apart. (Usually the student is expected to think that the particles get further apart, but it is logically more sensible to say they get larger. But neither answer is really satisfactory.)

If someone suggested that a mushroom must photosynthesise because that is how plants power their metabolism then they would have made a category error. (Yes, plants photosynthesise. However, a mushroom is not a plant but a fungus, and fungi are decomposers.)

The issue here, to my mind (so to speak) was the distinction between brain (a material object) and conscious mind (the locus of subjective experience). Whilst it is usually assumed that mind and brain are related (and that mind may arise, emerge from processes in the brain) they may be considered to relate to different levels of description. So, mind and brain are not just different terms for the same thing.

Mind might well arise from brain, but it is not the same kind of thing. So, perhaps the notion of 'tasks' applies to minds, not brains? (Figure from Taber, 2013)

So, it is one thing to claim that the mind can only be actively engaged in one task at a time, but that is not equivalent to suggesting this is true of the brain that gives rise to that mind.2

Prof. Dax seemed to be concerned with the brain:

"the brain…billions of neurons, trillions of synaptic connections… brain regions…lateral prefrontal cortex…populations of neurons"

Yet it seems completely unfounded to claim that human brains do not multitask as we surely know they do. Our brains are simultaneously processing information from our eyes, our ears, our skin, our muscles, etc. This is not some kind of serial process with the brain shifting from one focus to another, but is parallel processing, with different modules doing different things at the same time. Certainly, we cannot give conscious attention to all these inputs at once, so the brain is filtering and prioritising which signals are worth notifying to head office (so to speak). We are not aware of most of this activity – but then that is generally the case with our brains.

The brain controls the endocrine system. The brain stem has various functions, including regulating breathing and heart rate and balance. If the brain cannot multitask we had perhaps better hope it focuses on breathing, although even then I doubt we would survive for long based on that activity alone.

Like the proverbial iceberg, most of our brain activity takes place below the waterline, out of conscious awareness. This is not just the physiological regulation – but a lot of the cognitive processing. So, we consolidate memories and develop intuitions and have sudden insights because our brains are constantly (but preconsciously) processing new data in the light of structures constructed through past experience.

If you are reading, you may suddenly notice that the room has become cold, or that the doorbell is ringing. This is because although you were reading (courtesy of your brain), your brain was also monitoring various aspects of the environment to keep alert for a cue to change activity. You (as in a conscious person, a mind if you like) may not be able to do two things at once, so your reading is interrupted by the door bell, but only because your brain was processing sensory information in the background whilst it was also tracking the lines of text in your book, and interpreting the symbols on the page, and recalling relevant information to provide context (how that term was defined, what the author claimed she was going to demonstrate at the start of the chapter…). Your mind as the locus of your conscious experience cannot multi-task, certainly, and certainly "brain regions that are involved in…attention" are very relevant to that, but your brain itself is still a master of multitasking.

Me, mybrain, and I

So, if the brain can clearly multitask, can we say that the person cannot multitask?

That does not seem to work either. The person can thermoregulate, digest food, grow hair and nails, blink to moisten the eye etc., etc as they take an examination or watch a film. These are automatic functions. So, might we say that it is the body, not the person carrying out those physiological functions? (The body of the person, but not the person, that is.)

Yet, most people (i.e., persons) can hold a conversation as they walk along, and still manage to duck under an obstruction. The conversation requires our direct attention, but walking and swerving seem to be things which we can do on 'autopilot' even if not automatic like our heartbeat. But if there was a complex obstruction which required planning to get around, then the conversation would likely pause.

So, it is not the brain, the body, or even the person that cannot multitask, but more the focus of attention, the stream of consciousness, the conscious mind. Perhaps confusion slips in because these distinctions do not seem absolute as our [sic] sense of identify and embodiment can shift. I kick out (with my leg), but it is my leg which hurts, and perhaps my brain that is telling me it is hurting?

Figure by  by mohamed Hassan from Pixabay; background by  by Sad93 from Pixabay 

Meanwhile, my other brain was relaxing

There is also one sense in which I regularly multitask. I listen to music a lot. This includes, usually, when I am reading. And, usually, when I am writing. I like to think I can listen to music and work. (But Prof. Dux may suggest this is just another example of how humans "are not actually good at knowing our own limitations".)

I like to think it usually helps. I also know this is not indiscriminate. If I am doing serious reading I do not play music with lyrics as that may distract me from my reading. But sometimes when I am writing I will listen to songs (and, unfortunately for anyone in earshot, may even find I am singing along). I also know that for some activities I need to have familiar music and not listen to something new if the music is to support rather than disturb my activity.

Perhaps I am kidding myself, and am actually shifting back and forth between

being distracted from my work by my musicandfocusing on my work and ignoring the music.

I know that certainly sometimes is the case, but my impression is that usually I am aware of the music at a level that does not interfere with my work, and sometimes the music both seems to screen out extraneous noise and even provides a sense of flow and rhythm to my thinking.

The human brain has two somewhat self-contained, but connected, hemispheres. (Image by Gerd Altmann from Pixabay)

I suspect this has something to do with brain lateralisation and how, in a sense, we all have two brains (as the hemispheres are to some extent autonomous). Perhaps one of my hemispheres is quietly (sic) enjoying my music whilst the other is studiously working. I even fancy that my less verbal hemisphere is being kept on side by being fed music and so does not get bored (and so perhaps instigate a distracting daydream) whilst it waits for the other me, its conjoined twin, to finish reading or writing.

I may well be completely wrong about that.

Perhaps I am just as hopeless at multitasking with my propensity to attempt simultaneous scholarship and music appreciation as those people who think they can monitor social media whilst effectively studying.3 Perhaps it is just an excuse to listen to music when I should be working.

But even if that is so, I am confident my brain can multitask, even if I cannot.


Work cited:

Note:

1 The four minute warning, perhaps. But,

  • Apple are releasing a new iPhone next spring?
  • Another email has arrived inviting me to talk at some medical conference on a specialism I cannot even pronounce?
  • A fiend of a friend of a friend has posted some update on social media that I can put into Google translate if I can be bothered?
  • Someone I do not recall seems to have a job anniversary?
  • Someone somewhere seems to have read something I once wrote (and I can find out who and where for a fee)?

Luckily I have been notified immediately as now I know this I will obviously no longer wish to complete the activity I was in the middle of.

2 One could argue that when a person is conscious (be that awake, or dreaming) one task the brain is carrying out is supporting that conscious experience. So, anything else a brain of a conscious person is doing must be an additional task. Perhaps, the problem is that minds carry out tasks (which suggests an awareness of purpose), but brains are just actively processing?

3 As a sporting analogy for the contrast I am implying here, there is a tradition in England of attending international cricket matches, and listening to the 'test match special' commentary (i.e., verbal) on the radio while watching (i.e. visual) the match. This seems to offer complementary enhancement of the experience. But I have also often seen paying spectators on televised football matches looking at their mobile phones rather than watching the match.

Sleep can give us energy

Sleep, like food, can give us a bit more energy

Keith S. Taber

Image by Daniela Dimitrova from Pixabay 

Jim was a participant in the Understanding Science Project. When I was talking to students on that project I would ask them what they were studying in science, rather than ask them about my own agenda of topics. However, I was interested in the extent to which they integrated and linked their science knowledge, so I would from time to time ask if topics they told me about were linked with other topics they had discussed with me. The following extract is taken from the fourth of a sequence of interviews during Jim's first year in secondary school (Y7 in the English school system).

And earlier in the year, you were doing about dissolving sugar. Do you remember that?

Erm, yeah.

Do you think that's got anything to do with the human body?

Erm, we eat sugar.

Mm. True.

Gives us energy…It powers us.

Ah. And why do we need power do you think?

So we can move.

This seemed a reasonable response, but I was intrigued to know if Jim was yet aware of metabolism and how the tissues require a supply of sugar even when there is no obvious activity.

Ah what if you were a lazy person, say you were a very lazy rich person? And you were able to lie in bed all day, watch telly, whatever you like, didn't have to move, didn't have to budge an eyelid, … you're rich, your servants do everything for you? Would you till need energy?

Yes.

Why?

I dunno, 'cause being in bed's tired, tiring.

Is it?

When I'm ill, I stay off for a day, I just feel tired, and like at the end of the day, even more tired than I do when I come to school some times.

Jim's argument failed to allow for the difference in initial conditions

Staying in bed all day and avoiding exercise could indeed make one feel tired, but there seemed something of a confound here (being ill) and I wondered if the reason he stayed in bed on these days might be a factor in feeling even more tired than usual.

So maybe when you are ill, you should come to school, and then you would feel better?

No.

No, it doesn't work like that?

No.

Okay, so why do you think we get tired, when we are just lying, doing absolutely nothing?

Because, it's using a lot of our energy, doing something.

Hm, so even when we are lying at home ill, not doing anything, somehow we are using energy doing something, are we?

Yes.

What might that be, what might we use energy for?

Thinking.

I thought this was a good response, as I was not sure all students of his age would realise that thinking involved energy – although my own conceptualisation was in terms of cellular metabolism, and how thinking depend on transmitting electrical signals along axons and across synapses. I suspected Jim might not have been thinking in such terms.

Do you think it uses energy to think?

(Pause, c.3s)

Probably.

Why do you think that?

Well cause, like, when you haven't got any energy, you can't think, like the same as TV, when it hasn't got any energy, it can't work. So it's a bit like our brains, when we have not got enough energy we feel really tired, and we just want to go to sleep, which can give us more energy, a bit like food.

So Jim here offered an argument about cause and effect- when you haven't got any energy, you can't think. This would certainly be literally true (without any source of energy, no biological functioning would continue, including thinking) although of course Jim had clearly never experienced that absolute situation (as he was still alive to be interviewed), and was presumably referring to experiences of feeling mentally tired and not being able to concentrate.

He offered an analogy, that we are like televisions, in that we do not work without energy. The TV needs to be connected to an electrical supply, and the body needs food (such as sugar, as Jim had suggested) and oxygen. But Jim also used a simile – that sleep was like food. Sleep, like food, according to Jim could give us energy.

So sleeping can give us energy?

Yeah.

How does that work?

Er, it's like putting a battery onto charge, probably, you go to sleep, and then you don't have to do anything, for a little while, and you, then you wake up and you feel – less tired.

Okay so, you think you might need energy to think, because if you have not got any energy, you are very tired, you can't think very well, but somehow if you have a sleep, that might somehow bring the energy back?

Yeah.

So where does that energy come from?

(Pause c.2s)

Erm – dunno.

So here Jim used another analogy, sleeping was like charging a battery. When putting a battery on change, we connect it to a charger, but Jim did not suggest how sleep recharged us, except in that we could rest. When sleeping "you don't have to do anything, for a little while", which might explain a pause in depletion of energy supplies, but would not explain how energy levels were built up again.

[A potentially useful comparison here might have been a television, or a lap top used to watch programmes, with an internal battery, where the there is a buffer between the external supply, and the immediate source for functioning.]

This was an interesting response. At one level it was a deficient answer, as energy is conserved, and Jim's suggestion seemed to require energy to be created or to appear from some unspecified source.

Jim's responses here offered a number of interesting comparisons:

  • sleep is a bit like food in providing energy
  • not having energy and not being able to think is like a TV which cannot work without energy
  • sleeping is like putting a battery on charge

Both science, and science teaching/communication draw a good deal on similes, metaphors and analogies, but they tend to function as interim tools (sources of creative ideas that scientists can then further explore; or means to help someone get a {metaphorical!} foothold on an idea that needs to later be more formally understood).

The idea that sleeping works like recharging a battery could act as an associative learning impediment as there is a flaw in the analogy: putting a battery on charge connects it to an external power source; sleep is incredibility important for various (energy requiring) processes that maintain physical and mental health, and helps us feel rested, but does not in itself source energy. Someone who thought that sleeping works like recharging a battery will not need to wonder how the body accesses energy during sleep as they they seem to have an explanation. (They have access to a pseudo-explanation: sleep restores our energy levels because it is like recharging a battery.)

Jim's discourse reflects what has been called 'the natural attitude' or the 'lifeworld', the way we understand common experiences and talk about them in everyday life. It is common folk knowledge that resting gives you energy (indeed, both exercise and rest are commonly said to give people energy!)

In 'the lifeworld', we run out of energy, we recharge our batteries by resting, and sleep gives us energy. Probably even many science teachers use such expressions when off duty. Each of these notions is strictly incorrect from the scientific perspective. A belief that sleep gives you energy would be an alternative conception, and one that could act as a grounded learning impediment, getting in the way of learning the scientific account.

Yet they each also offer a potential entry point to understanding the scientific accounts. In one respect, Jim has useful 'resources' that can be built on to learn about metabolism, as long as the habitual use of technically incorrect, but common everyday, ways of talking do not act as learning impediments by making it difficult to appreciate how the science teacher is using similar language to express a somewhat different set of ideas.