Interview on “Absent-mindedness”

In connection with the publication of the Physical Review E paper, there was a live broadcast interview for laypersons in Radio Sweden, P4 Sjuhärad on the topic of absent-mindedness by the reporters Sara Nygren and Anna Engström. Since the interview is in Swedish, I have added an English translation below. Play interview

Transcript in English

(Sara Nygren and Anna Engström)


“Learn as long as you live” with Lena Philipsson, and you would imagine one could do just that. As for absent-mindedness, people have often told me that I will probably improve when I grow older. That hasn’t quite worked out the way I hoped, but on Facebook today, and generally on our social media, you can join in and share stories of when absent-mindedness has caused you some embarrassment.

When Pia forgot to fetch her son at the airport, they called and asked: “We have a kid here, could he possibly be yours?”. “Oh yes”, said Pia, “but I wasn’t supposed to fetch him until tomorrow”. Or Ann-Katrin, who had lost her bike somewhere. I can really recognize myself in that situation, too. I have been somewhere, often by car in my case, which I have parked somewhere, and then when I return to the parking area, it is not at all at that parking, but somewhere else where I’ve parked it. You have to activate the little brain cells up there and we are talking about absent-mindedness today, because we absent-minded are not alone, and now, there is new research about this. That is why we called the very composed Martin Nilsson, mathematical physicist and associate professor at RISE.

Good morning, Martin!

Good morning!

Are you absent-minded, by the way?

There is no end to my absent-mindedness!


But I’m proud of it.

Is it true?

Yes, I would say that absent-mindedness is a form of creativity. I see absent-mindedness as ideas popping up from nowhere, sudden ideas about something else than what we are currently doing.

I can identify with that! But what happens in the head when we are absent-minded?

I think that the common factor is that new thoughts seem to appear randomly, and perhaps overtake our originally thoughts. An old philosophical question is if this appearance is really random, or if the brain function is determined uniquely by environmental interactions and hereditary properties. Is there some kind of “dice throwing” which causes these things to happen?

How nice if it isn’t my own fault that I’m so absent-minded!

Yes, one could say that absent-mindedness is a very high-level property, but to investigate if there is a fundamental mechanism in the brain that generates randomness, we descended down to study single nerve cells, to see if we could find something there.

And what did you find?

We actually found something very exciting! We started from experimental measurements. My colleague Henrik Jörntell from Lund University, who is a phenomenal experimentalist, had measurements from nerve cells, and that was our glass shoe. My job was to find a theoretical model for this. It was to find Cinderella and try to fit these two together.

Then did you do it? Did you find her before midnight?

Yes, I would say we did. It was quite a small Cinderella in a very large hay stack.

Wow, but did you find her eventually?

Yes, I think so. She consists of four differential equations. The first three look fairly normal, but in the fourth I discovered a random term, whose origin took a while to figure out. This model describes how a nerve cell works, and its function is based valves placed in the cell’s “wall”, called the cell membrane. The valves are known as ion channels, and send currents mostly consisting of sodium and potassium ions into and out of the cell. You would think that these valves are sitting immobile in the cell membrane, but they aren’t. The molecules in the cell membrane travel around, akin to the bumper cars in the amusement park Liseberg, bumping into each other. This causes the ion channels to open and close somewhat randomly.

I see.

It turns out that this function is incredibly important for the communication between the nerve cells.

Then does it mean that these channels happen to be open for business exactly when a new thought appears, which is completely unrelated to the thought I should be thinking, so that I cling on to the new one instead?

Well, these ion channels correspond approximately the low-level transistors in a computer, and the absent-mindedness corresponds to properties of the high-level user programs, so there is a tremendous level difference here. But the low-level randomness can be amplified, and may influence the cell so that it becomes impossible to predict what it will do. In other words, there will be a built-in random factor, which can be small or large, but which can potentially affect the function of the system as a whole. So, you can never be completely sure that things go the way you think, and there is always a possibility for the brain to do something completely unexpected.

How sweet a tune it is to hear you speak, Martin Nilsson! About absent-mindedness and what it is actually doing there inside the head, we’ll very soon continue the discussion here in the P4 studio.


I’m talking about absent-mindedness together with Martin Nilsson, who is associate professor at RISE and who is studying what happens in the brain. You just told us that we can never be sure that our thoughts will go the way we had expected, Martin Nilsson. What have you found that is new? What wasn’t known before?

It is this randomness property. It has been difficult for the research community to accept that there is randomness in the nervous system. Preferably, behaviour should be deterministic. Input should determine the output uniquely. And now it has turned out—and we have strong support for it—that this randomness is quite fundamental. The nerve cells would simply not work without it. In addition, the brain needs randomness for expressing vagueness; you cannot always be so precise, and then you have to express it somehow.

I think it is especially beautiful when a mathematician says this.

Well, it was quite fun when we matched the experimental results with the theory and found that, although there was randomness, it was highly regulated randomness. It can be described very concisely, and this was a surprising experience.

You know, in my life, absent-mindedness has often been considered sloppy, something to improve upon. I shouldn’t let my mind wander away like that in a world of my own, watching the wall and thinking of something else. Are there advantages to being absent-minded? Can you affirm this now while I have you online?

I think you should see it as an asset, not as a shortcoming. Consider the ability to have these spontaneous ideas a form of creativity. I associate it with one of the best movies I have seen, “Le Fabuleux Destin d’Amélie Poulain”. I don’t know if you have seen it…

Yes, I have.

…otherwise, I can recommend it. It is very inspiring. Your absent-mindedness is a strength!

OK, but these new research results at RISE and elsewhere, what can you use them for in the future?

The basic understanding of the nerve cell is very important, of course. Nerve cells have been studied in detail for more than one hundred years, but there is still no general consensus of exactly what they are doing. Understanding them is essential for treating brain disorders, but also for improving systems for AI and machine learning, which are increasingly inspired by biology.

Oh my God, will we have a lot of absent-minded robots walking around here soon?


I don’t think so. But I do believe that in order to demonstrate human-level intelligence, some degree of randomness is necessary.

But you know, I have thought about this now, when you told us that you have entered the brain and studied the very minute components in there. How do you do it? Do you put somebody in a room and tell them to think of a few things, or how do you do it in practice? How do you study absent-mindedness?

Well, experiments are really my colleague Henrik Jörntell’s specialty, but I can say that the activity of nerve cells is measured with electrodes. The nerve cells pass electrical signals to each other, and these can be recorded. The signals consist of electrical pulses at intervals, which form irregular patterns. These intervals are the input data we have. The meaning of these intervals has been a subject of intense discussions for a long time. Do they carry a meaningful signal of some kind or are they totally random? The distribution of the intervals can be studied mathematically to see if they follow a rule, and we succeeded in finding that rule.

Was that a “eureka moment” when you found it?

Yes, it was quite a “Sesame open”, it really was!


Yes, as a scientist I must say that is the kind of experience you really long for, because we had such an extremely good fit. And that is why we dare to claim that this is probably the way nerve cells really work.

If we conclude now, as you know, there are many who use their weaknesses as super powers. Can we say boldly that absent-mindedness is a super power, with the consent of science?

Well, I wouldn’t formulate it as absent-mindedness, but I would say that having spontaneous ideas is a super power!


The ability to think outside the box, that is a true asset.

Now I will always refer to you, Martin Nilsson, mathematical physicist, associate professor at RISE. We have discussed and agree that absent-mindedness is normal! You are normal! Thank you for joining us, Martin!

Thank you, too!