英语语言学习：大脑训练有用吗

Norman Swan: Amit Etkin is in the Department of Psychiatry and Behavioral Sciences at Stanford University in California

Amit referred to computer-based brain training. In fact this is all the rage at the moment with a big emphasis on staving off dementia. But probably the best studied brain training programs are aimed at what's called working memory in both children and adults. The question is though, do they work?

Megan Spencer-Smith and a colleague from Sweden have tried to find out by bringing together the evidence.

Megan Spencer-Smith: Working memory difficulties are often observed in behaviour. So teachers and parents and also adults who have problems with working memory might notice that they are forgetting things in their daily life, they are finding that when people are talking to them they can't keep track of that conversation if it's a complex conversation, that type of thing.

Norman Swan: So it's about attention.

Megan Spencer-Smith: That's right. So working memory problems can be observed in attention in daily life.

Norman Swan: And this is why there is an overlap with attention deficit hyperactivity disorder because inattention is part of that problem.

Megan Spencer-Smith: That's right. And for children and adults with a diagnosis of ADHD, they are commonly described as having deficits in what is called visual spatial working memory.

Norman Swan: And what's that?

Megan Spencer-Smith: It's this ability to hold visual information and visual spatial information in mind and work with it. There's also another type of working memory called verbal working memory, and that information is, for example, me talking to you, trying to remember a phone number that someone might tell you out loud, that's described as a verbal working memory.

Norman Swan: So you're talking about both?

Megan Spencer-Smith: That's right.

Norman Swan: And if you've got a visual spatial problem, how does that manifest itself?

Megan Spencer-Smith: For example, if they are in a lecture theatre and they are trying to use the information that is presented to them visually and they are trying to write notes, that sort of task can be quite complex if you have some low working memory or working memory problems.

Norman Swan: And what is working memory? Is this a bit like the RAM in your computer?

Megan Spencer-Smith: That's a really good analogy. Working memory is this cognitive ability to hold information in mind and then work with that information over a short period of time. For example, trying to solve mental arithmetic problems.

Norman Swan: It's stuff that's coming fresh into your brain from the environment, you are holding that in some sort of abstract space in your head, then retrieving stuff from your brain which you require to solve the problem and it's all in a mixmaster there in your brain while you solve the problem, and some people just can't…there's a leakage, if you like, which doesn't allow you to hold it long enough to solve the problem or get on with the task.

Megan Spencer-Smith: That's right, you describe it really well, yes.

Norman Swan: What training is around? And I should say here that we are slightly conflicted in this conversation in that your co-author is a consultant for one of the companies that produces one of these programs, but in general what's available on the market for working training?

Megan Spencer-Smith: There's quite a few programs that have been developed targeting working memory, so we call them computerised working memory training programs. There are some programs that have been developed just for research purposes, and then there's some programs that are now available commercially.

Norman Swan: Having evolved from research programs.

Megan Spencer-Smith: That's correct.

Norman Swan: And so in general what do they do though?

Megan Spencer-Smith: In general the individual would be on a computer, and they are training on tasks that are presented on a computer or on an iPad. These training tasks are visual spatial working memory tasks or they are verbal working memory tasks or they are using a combination of both. So they are training repeatedly on these tasks over many weeks and over many days.

Norman Swan: And it's not skills training, it's actually training the nerves in your brain to network and control, and it's making connections in your brain that otherwise would not have been made.

Megan Spencer-Smith: That's right, we are trying to strengthen those connections, and there's also some evidence from neuroscience research demonstrating that a working memory training program can change brain structure and function.

Norman Swan: Yes, for example, if you learn the violin you can actually see that effect physically in the brain rather than some abstract notion of electrical networks.

Megan Spencer-Smith: Yes.

Norman Swan: And what sort of research has been done in this area? Because normally when you bring together the available evidence, it's usually from randomised controlled trials, you know, somebody gets a placebo and you measure the two and see what the real effect is. Is that the sort of evidence that is available on these working memory training programs?

Megan Spencer-Smith: Yes, there has been an accumulation of research over the last 10 years, and there are quite a few randomised controlled trial designed studies evaluating the effects of these different working memory training programs, compared with a control group.

Norman Swan: So that's what you did, you brought together the available studies in what's called a meta-analysis or a systematic review. What did you find?

Megan Spencer-Smith: When we systematically researched the literature and we also contacted researchers who are in the area who might not have published their data, when we pulled the results from those studies together we identified 11 studies that have a control group and an intervention group, and these studies were reporting on inattention in daily life. So that's a measure of a generalising benefit of the working memory training program.

Norman Swan: It's one thing to say that…and neuropsychologists get very excited about this, is that you've improved on these neuropsychological measures and isn't that wonderful, and notoriously it has been done on drugs and dementia. And actually when you ask people whether it changes their daily life, it's barely noticeable. How many of those studies actually looked at whether or not it was improving the quality of people's lives or the quality of their brain function that they noticed a difference rather than on fancy neuropsychological tests?

Megan Spencer-Smith: That's a really good question and it's something that we wanted to address in the meta-analysis. So we focused on studies that were reporting on benefits in daily life. So either the individual himself or a teacher or a parent describes that individual's behaviour by rating their behaviour.

Norman Swan: So are they sticking to task, are they achieving tasks, are they remembering things better et cetera?

Megan Spencer-Smith: That's correct.

Norman Swan: So what did you find?

Megan Spencer-Smith: So we found that when we compared these 11 studies with an intervention and control group and pulled the data together and did the meta-analysis, this main analysis showed that the treatment effect was significant and also moderate. So the effect size was 0.47.

Norman Swan: What does that mean?

Megan Spencer-Smith: That's an effect size described often as moderate or moderate to large. For example, when we look at the effects of pharmacological treatments that are trying to address behaviour problems such as antidepressants, the effect sizes there are generally around 0.3. So an effect size of 0.47 is impressive, and the initial evidence is encouraging.

Norman Swan: What are the elements of a training system that people should be looking for if they are thinking of taking up one of these working training programs?

Megan Spencer-Smith: The programs that are often discussed in the literature as having benefits for daily life, these programs have an adaptive approach, constantly pushing the individual to their capacity based on their own performance on a trial by trial basis.

Norman Swan: What should you look for in the tasks themselves? What are the elements of the tasks that are likely to track you to practical improvement?

Megan Spencer-Smith: At the moment that is being studied. So whether, for example, training on verbal working memory tasks or visual spatial working memory tasks are most beneficial, that isn't quite clear at the moment. Some other aspects of a program that seem to be important are factors such as motivation. So this is important for making sure that the individuals are completing the program, we are asking them to do demanding tasks for quite a long time.

Norman Swan: And what does a long time actually mean?

Megan Spencer-Smith: The training programs can range in length. The program that we focused on has a program that is five weeks long, and the individuals are asked to train every day, five days a week over those five weeks.

Norman Swan: So if a program offers you a quick fix, run for the hills.

Megan Spencer-Smith: You might want to ask some questions, yes.

Norman Swan: And is it different for kids and for adults?

Megan Spencer-Smith: The difference between those programs is minimal and it's just the interface. So this idea of trying to engage a child to keep motivated for five weeks, whereas adults perhaps they wouldn't be motivated by the same format as a child.

Norman Swan: It's assumed that these things have no harms, but that's not necessarily a fair assumption. Did any of the studies measure harm?

Megan Spencer-Smith: Harm is something that hasn't been discussed so much in the literature. There is discussion about whether asking an individual to train for that amount of time without benefits, that is something that's concerning and that's why it's important that we do these trials to make sure that if we are asking someone to do such a large commitment and pay money, that there are real benefits.

Norman Swan: Megan Spencer-Smith, thanks for joining us on the Health Report.

Megan Spencer-Smith: Thank you Norman.

Norman Swan: Dr Megan Spencer-Smith is in the School of Psychological Sciences at Monash University . . .