Now then, Dr. Kawashima… The training in this new title really is quite challenging! (laughs)
It is! (laughs) That’s why it’s called Devilish Brain Training. To be honest, I basically made it with myself in mind...
You made it for yourself?! (laughs)
Well, you know, I’m over 50 now – as are you – and when I’m up against energetic graduate students in their 20s, my head just doesn’t work the way I wish it would…
And you forget things, right?
I do! (laughs) Sometimes the students show me up, and I don’t like that. As a doctor, I want to stay on top, and stay in control!
You want to be able to show them who’s boss – and be certain that you can win in a one-on-one confrontation!
Exactly. If I think honestly about where my students have the edge, it’s working memory. I know that working memory deteriorates drastically with age, so I want a way of improving it on the sly...
We are going to release this as a game, you know…! (laughs)
Yes, but I still don’t want to tell the people around me what I’m up to! (laughs) I want to retrain my working memory so that my brain works the way it did when I was young. I have much more knowledge now than I did back then, so if I can process that knowledge better, I’ll be invincible for a while. That’s my ambition anyway! (laughs)
(laughs) So while you do want Devilish Brain Training to make a contribution to society, it’s also for your own benefit!
Speaking of making a contribution to society, I want to recommend Devilish Brain Training to young people who are studying at the moment.
Well, the action of ‘memorising’ is all about retrieving information at the right time after placing it in your working memory. The capacity and functioning of your working memory therefore determines whether you are good or bad at remembering things.
Exactly. Accordingly, it can be considered that using Devilish Brain Training to study for exams can contribute to improve your results. The greater the capacity of your working memory, the more information you’ve got ‘online’, so to speak, and the more accurate and precise your decisions become. I also recommend it for people in work, therefore, since they need to be able to make split-second decisions.
It was refreshing to hear you say that people should play this game for five minutes every day, but not to overdo it. You have discovered that this training may not necessarily be better the more you do it, haven’t you?
That’s right. I tested the training on some of my students. There was one student who wanted to improve their brain functions by training very intensively for a short period of time. They trained for about four to six hours every day.
Six hours each day of that exhausting training?!
Yes. There’s no way I could do it. But the students of The Kawashima Laboratory are hardy. They were also being paid part-time wages, which probably helped with motivation! (laughs)
After about five days, we measured the student’s brain activity. What amazed us was that the capacity of the cerebral cortex, which we had expected to increase, had actually decreased. The data showed their brain had actually slimmed down.
What do you mean by the brain ‘slimming down’?
Well, this is one possible explanation: I said earlier that the thickness of the cerebral cortex peaks at about 8 to 10 years of age before, becoming slimmer as it develops. The exact same thing may have happened here. The brain may have become a better functioning organ with a more effective network, but a smaller capacity.
I do think that is a bit of a contradiction, though… I’m currently researching why short play sessions for a month increase the capacity of the brain but long play sessions over a concentrated period decrease it. I’m also trying to find the cause of the switch between increasing and decreasing capacity.
In the case of this student, the region of the prefrontal area that had decreased in capacity the most was the region responsible for interpersonal communication. The research results must have shown that more isn’t always better, I think.
You felt there was a good chance that the changes caused weren’t positive ones?
Yes. Training for six hours a day, has an effect on the other 18 hours as well. In a way, you’re sacrificing the rest of the day. In other words, I interpreted the results to mean that brain volume may have decreased because the part of the brain used for interpersonal communication wasn’t used.
Of course, we still don’t know the real explanation, so our conclusion is that until the cause is clarified, it’s best not to play for a long time.77 Devilish Brain Training trains your working memory using eight types of exercises. The software only allows players to play each exercise for about five minutes once a day. (A maximum of about 40 minutes a day (5 minutes × 8 exercise types)).
What have you learned since you started focusing on working memory?
Well, at first, all we understood were the ‘entrance’ and ‘exit’ of working memory. That is, its inputs and outputs. If you practise activities such as reading, writing, and arithmetic (the input); various capabilities will improve (the output). We then established that practising the three Rs makes the prefrontal area work a lot – in other words, we discovered one of the functions of the ‘entrance’ side of the brain. Later, as we investigated why that happens, we learned that improving the brain’s processing speed has other knock-on effects, which is why the previous Brain Training focused on boosting this processing speed.
That’s why Calculations × 20 8 is timed, isn’t it?8 Calculations × 20 is one of the training exercises in Brain Training: How Old is Your Brain? Players must fill in the answers to simple arithmetic problems that appear one after the other, trying to answer 20 problems as quickly as possible. The same exercise is included in Devilish Brain Training as Training Supplements.
That’s right. However, a good working memory requires both speed and capacity. The part of the brain that works at great speed when practising the three Rs only uses the working memory capacity that someone already possesses. We are learning that rather than increasing the speed of the original working memory, increasing its capacity is more effective at improving a variety of brain functions.
As experiments in increasing working memory capacity, we carried out psychological training using ‘n-back’ exercises9 and ‘span’ exercises10 – both of which are included in Devilish Brain Training. The results showed that various brain functions improve, just as they do when the three Rs are practised.9 N-back exercises require the player to provide the answer to a problem that was displayed N number of times earlier, rather than the answer to the problem currently displayed. ‘1-back’ requires players to provide the answer for the previously displayed problem, ‘2-back’ requires players to provide the answer for the problem displayed two times previously, and so on.10 Span exercises require players to watch as nine symbols in a 3 × 3 grid flash randomly one at a time. The players try to remember the order in which they flash.
It seems that the depth and breadth of your ability to answer the question of ‘what happens when you play Brain Training?’ has increased, Dr. Kawashima?
Oh yes, it is completely different to how it was before. I now have fairly good explanation for why the ‘entrance’ and the ‘exit’ are connected. Further experiments should give me an even clearer understanding.
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