Shownotes
In this episode, Dr Marie-Josee Bisson asks Dr Walter Van Heuven about language organisation in the brain. How does the brain cope with having words in different languages and how come we don't make lots of mistakes when we speak (for example saying a word in French in the middle of a conversation in English!). Listen to the episode to find out!
To find out more behind-the-scenes information about this topic or about our podcast, please visit our webpage, languagescientists.dmu.ac.uk. This is where you can go to ask questions, leave comments, or even participate in our current research! We'd love to hear from YOU.
Follow Dr Zavaleta and Dr Bisson on twitter: @dr_klzavaleta and @mjbisson
Or get in touch via email: kaitlyn.zavaleta@dmu.ac.uk and marie-josee.bisson@dmu.ac.uk
Link to Dr Van Heuven's research lab: https://waltervanheuven.net/
Example article about Dr Van Heuven's research:
van Heuven, W.J.B., Schriefers, H., Dijkstra, T., & Hagoort, P. (2008). Language conflict in the bilingual brain. Cerebral Cortex, 18, 2706-2716.https://dx.doi.org/10.1093/cercor/bhn030
Transcripts
Dr Marie-Josee Bisson
If you have connection to languages, this is the podcast for you. Whether you're a language learner, a language teacher, a language researcher, or anyone who's interested in languages. I'm Dr. Marie-Josee Bisson, and alongside my colleague, Dr. Kaitlyn Zavaleta, we are the language scientists and this is our podcast. We are both senior lecturers in psychology at De Montfort University, and we conduct research into the area of language learning. Throughout the series, we hope to translate the science behind language learning into informative and useful practical advice. So sit back and enjoy. Today we are joined by Dr. Walter Van Heuven from the University of Nottingham who will talk to us about language in the brain. Welcome, Walter.
Dr Walter Van Heuven
Hello.
Dr Marie-Josee Bisson
Walter is an associate professor in psychology at the University of Nottingham. He did one year of a computer science, an undergraduate degree, and ended up continuing with cognitive science. And this was at the University of Nijmegen in the Netherlands. He then completed a PhD also in Nijmegen and he did one postdoc in Nijmegen and another one at the University of Aix en Provence. To finish, he took a position at the University of Nottingham and he is still there today. I was extremely lucky to have Walter as my principal supervisor for my PhD and I'm really excited to have him here today. So you're so welcome.
Dr Walter Van Heuven
Thank you.
Dr Marie-Josee Bisson
Now before we jump into the topic of today, we always ask our contributors to tell us a little bit about their language background. Would you mind?
Dr Walter Van Heuven
Yeah. And so, yeah, I my first language, of course, is Dutch. And so I started learning other languages in school at secondary school, so quite late. But I was of course, exposed to a lot of other languages when I was a child through television. So I got quite a lot of input through German television because in my time when I was a child, there was not much television. Certainly there was only one channel in Holland, but there were quite a few channel channels that we could pick up from German television. So as a child, I watched a few times a week German television.
Dr Marie-Josee Bisson
So lots of German cartoons.
Dr Walter Van Heuven
So German cartoons and programmes. So I got exposed to German. So I picked up, I think a little bit of German that way. But in terms of formal education, it started in secondary school with German, French and English.
Dr Marie-Josee Bisson
He did three languages at secondary school.
Dr Walter Van Heuven
We had to do three languages.
Dr Marie-Josee Bisson
That's amazing.
Dr Walter Van Heuven
To start with. Yeah. And then if you were good at languages, you could continue. Of course you could chose those languages, but I just kept English as another the language. So that's yeah, in Holland you have to do English up to your exams.
Dr Marie-Josee Bisson
Yeah. Wow. Okay. And now your German is still, still there.
Dr Walter Van Heuven
Well, I can understand it. I can read it, but speaking is a big less. And French is is weaker than my German. A little bit of understanding. French. Yeah.
Dr Marie-Josee Bisson
And maybe when you spent a year in Aix en Provence, that probably helps your french a little bit. That helps a little bit, Yeah, definitely. The exposure to French. Yeah. There was, was quite, quite helpful. Yeah.
Dr Marie-Josee Bisson
So how did you become interested in doing language research.
Dr Walter Van Heuven
Yeah. So that's quite interesting because yeah, as you said I started at computer science, not really knowing what I wanted to do with computer science. And yeah, I think I got inspired by reading a book actually on about cognitive science, and I discovered, Oh, that's really interesting. It was about psychology, it was about language, linguistics and artificial intelligence. And then I discovered there was an opportunity to, after one year of computer science, to switch to a cognitive science course, which was a three year course, which people could do after a year of psychology or linguistics or computer science. And when I started, of course, I was very excited. There was really lots of interesting topics in terms of cognitive psychology and also language. And I had a fantastic teacher there who was very inspiring in terms of language research, psycholinguistics, and I ended up doing a project with him and that was my start into, into bilingualism.
Dr Marie-Josee Bisson
It's amazing because it's like that one event that has made your career the way it is not today.
Dr Walter Van Heuven
Exactly.
Dr Marie-Josee Bisson
The research you've done in terms of language and language in the brain, bilingualism and all of that. So that all came from that one project that you did with that one inspired inspirational teacher.
Dr Walter Van Heuven
Yeah.
Dr Marie-Josee Bisson
It's always so interesting to hear about how people ended up where they are now and like the journeys can the journeys can be so interesting. Well, so thank you for sharing that today. I invited you here in particular because I wanted to ask you about language in the brain. I think that's quite an interesting topic as we get more and more fluent. In another language. And we are learning more and more words and sometimes known words in both of these languages at the same time. So how does our brain cope with the different languages?
Dr Walter Van Heuven
Yeah, that's a that's a really interesting and important question, of course, in terms of how the brain deals with multiple languages. If you learn another language, of course you would need to have some organisation in the brain where these words are stored and knowledge about its meaning and you know knowledge about how the words are pronounced, how they are written. All that information needs to be stored and the question is how is it stored. Is it not tightly stored in different areas of the brain, or is it kind of a mixture where it's not clear where exactly this information is. And you would think that maybe the brain is smart and stores it all in separate locations and keeps it very nice and organised. But that's not happening.
Dr Marie-Josee Bisson
In reality and also, you know, obviously when you see models of of language learning or cognitive models, you know, you see those kind of boxes and arrows, kind of things and you have L1 for the first language, L2 for the second language, as if those things are completely separate in the brain. But you're saying that is not it.
Dr Marie-Josee Bisson
No, that's that's not the case. And it would be very nice if it was the case that was neatly, neatly organised in that way. But it's clearly isn't. And, and also even if it was kind of separated, of course the brain is highly interconnected, the neurones are highly interconnected. That means even if there is a nice separation,it doesn't mean that they are not connected. And that's a very difficult to distinguish, you know, where it is and also whether or not it is connected. And in terms of the the the research has very clearly shown that most of the languages are in terms of where it is activated in the brain is very similar in terms of a first and second language. So you see very similar activation patterns in terms of brain activity for first and second language. And then there's a lot of regions that have looked at whether both languages are activated simultaneously or specifically for the language that is relevant at a particular moment. For example, if you speak.
Dr Marie-Josee Bisson
Yeah, because we're I mean, we're both non-native speakers of English conversing here easily ish. I want to say it's easy, I guess, you know, we're speaking your non non-native language. Why is my French not coming out and speaking to you? And why are you not speaking Dutch to me, you know.
Dr Walter Van Heuven
Yeah.
Dr Marie-Josee Bisson
That's, that's amazing.
Dr Walter Van Heuven
That's indeed an amazing, amazing ability of, of bilinguals to be able to control their languages in such a way that we are not you're not suddenly speaking French and I'm not speaking Dutch. And so clearly the brain has developed very effective control mechanisms to prevent yourself speaking the wrong language to a person that doesn't speak that language now it doesn't mean that this is perfect, because you might notice in our conversation that I might slip a word of another language in there. So it's not, clearly not perfect. And there's a lot of research looked at looking at speech errors, for example.
Dr Marie-Josee Bisson
Kaitlyn's research.
Dr Walter Van Heuven
Oh yeah.
Dr Marie-Josee Bisson
My co-host. Yes, we have actually an episode on her research, which is on speech errors.
Dr Walter Van Heuven
Yeah.
Dr Kaitlyn Zavaleta
And she loves them, basically. But yeah, we had this conversation where, I mean, I hate it when I make a mistake. I feel so embarrassed when I'm speaking in English to somebody and suddenly something comes out in French is so odd and I feel so weird about it. But she was always like, Wow, let's think about this beautiful mistake and why did it happen? What does it tell us?
Dr Walter Van Heuven
Indeed. Yeah, it's very informative in terms of how the other languages are activated actually all the time. So these things can happen. And of course, if you speak to someone who is multilingual and then when then you see that bilinguals use multiple languages, just use the word that is most appropriate for the context. But if that's not the case, if you speak to someone who doesn't speak the same languages as yourself, you need to have effective control mechanisms. Bilinguals are quite good at that, but it doesn't mean that the other languages are not active.
Dr Marie-Josee Bisson
How do we know that the other languages are active at the same time?
Dr Walter Van Heuven
Yeah, that's a that's a really good question. So how can we investigate the activation of multiple languages? Now, you can do that in various ways. You can do that by presenting material on multiple languages, but also you can use specific material that word material or sentence material that has some similarity across languages. So for example, if you think about a single word, so my research is mostly focused on single words, there are words that exist in both languages that have the same meaning. And these words are called cognates. And they can be, they can have the same written form or the same spoken form, they sound very similar, but a crucial thing is that they have the same meaning. So for example, a word like film is an is in Dutch, word is an English word. And that's a cognate. And then you have words that are called false friends, that are valid words in two languages, but they have completely different meanings.
Dr Marie-Josee Bisson
Mm hmm.
Dr Walter Van Heuven
So an example in Dutch, in English is the word room. In Dutch, it's pronounced as room. In Dutch it means cream. But in English, of course, it means a room.
Dr Marie-Josee Bisson
So is the spelling of the Dutch word the same as the English word?
Dr Walter Van Heuven
Yeah, and exactly the same spelling. And in some cases, you have words that have the same spelling, but also very similar pronunciation.
Dr Marie-Josee Bisson
Mm hmm.
Dr Walter Van Heuven
These kind of words, of course, are very interesting because what happens if you present these words to a bilingual that has the knowledge of Dutch and English? And will they be aware of the existence of that word in two languages and how do they pronounce the word, for example, and what meaning will become available. So if they are seeing only Dutch words is it the case that they would interpret it as cream, as the Dutch would pronounce it like a room? Or would they then still consider it as an English word? And so that's an interesting question. And that kind of material can give you insite in terms of the activation of both languages. Is that is that the case? Both languages are activated or not? So homographs, so homographs. They're also called false friends. It's interesting material, cognates. And you have also material that is kind of words that have a very similar orthographic form in two languages. And that gives you also an opportunity to look at the role of othographic similarity between two languages. And you can investigate whether the similarity to words in another language influences how people process those words.
Dr Marie-Josee Bisson
Yes, really fascinating. I mean, we we also have an episode on orthographic, cross linguistic orthagraphic similarity. Obviously, I've done some research on that as well, and that's really fascinating. Although I did not use cognates in my research, and I know that you've you've used cognates in yours. So can you tell us what you found out then? Because I know you did that project with the false friends, the home example. Yeah, the cream and Dutch and room in English. What did you find?
Dr Walter Van Heuven
Yeah. So this this study was specifically looking at the question when you when you present those words to participants, are participants able to just focus on English and just ignore that Dutch? If that is the case, then processing words like room would be no different from other English words that do not exist in Dutch. However, if the Dutch plays a role, then the processing of this word room would be affected by Dutch knowledge. And so that was the kind of question because there was some evidence in the literature presented where they argued that people are able to control the languages in such a way that you you don't see influences of the other language, and it's specifically in one particular language context. So you only present English words. So we we did fMRI study. So in an MRI scanner we scanned the brains of people doing a very simple task, just deciding whether letter strings are correct, English words or not. And part of the material where those false friends and then carefully matched control words that were just English words.
Dr Marie-Josee Bisson
Yeah.
Dr Walter Van Heuven
And then we we looked at the brain imaging data to see which area differ then from a normal English words. And what we found was that in terms of response times, in terms of how fast people decide whether it's an English word or not, you see that people are much slower when there are English, when these are for these false friends compared to control words.
Dr Marie-Josee Bisson
Okay. So there's a?
Dr Walter Van e
So there is a behavioural kind of.
Dr Marie-Josee Bisson
Slowing down.
Dr Walter Van Heuven
A slowing down effect because people realise, oh, these are also Dutch words and they have to decide whether it's in English word.
Dr Marie-Josee Bisson
Yes.
Dr Walter Van Heuven
So what to do?
Dr Marie-Josee Bisson
It makes a bit of a slight conflict.
Dr Walter Van Heuven
Exactly. And it was this conflict that we were very much interested in. So what kind of conflict is happening there? Because it could be at a level of the fact that people realise that this word has two meanings, meaning in Dutch and in meaning in English. It has two pronunciations, but at the same time also it has a conflict in terms of what to respond. Is it Yes. Is it an English word or is it no because it's it's a Dutch word. And so that there that was really useful is then to look at the brain imaging data, because that can give us some kind of indication of what kind of conflict it is. And looking at the brain imaging data, it was very clear there were two main areas in the brain that that showed a difference. And it was an area in the medial frontal area of the brain which is very sensitive to what they call response conflict.
Dr Marie-Josee Bisson
Yeah.
Dr Walter Van Heuven
And another area, it was the left and the right prefrontal cortex, which is an area that is to do with control and so language control.
Dr Marie-Josee Bisson
Cognitive control.
Dr Walter Van Heuven
Cognitive control and retrieval as well of information. So those two areas don't tell us really very much about the potential of these different conflicts, because it could be both that are responsive to response conflict or stimulus conflict. So the critical comparison that we then did, it that we changed, we did exactly the same experiment. But rather than telling people you need to decide whether each letter string is an English word, we told them you need to decide whether it's a word and it doesn't matter which language.
Dr Marie-Josee Bisson
Okay.
Dr Walter Van Heuven
So it was a very subtle changes.
Dr Marie-Josee Bisson
But it would lead to the same response. It would be a yes kind of response in terms of response conflict there isn't because they would say yes to each.
Dr Walter Van Heuven
Exactly. It doesn't matter whether it's a Dutch or English word in all these cases that they can press yes. So there should be no response conflict. And I looked at the brain imaging data. It was really surprising because we saw no activation in the medial frontal cortex, and that was completely gone. But there was still activity in the left and right prefrontal cortex. And that means that the response conflict is really located in this medial frontal cortex.
Dr Marie-Josee Bisson
So it was due to the language themselves being both activated.
Dr Walter Van Heuven
Yeah, it was because both languages are, in both cases activated. But in one case it didn't matter which response. Well, it mattered in a sense. They had to press yes, for any language. So there was no response to conflict. And that means that that particular area of the brain is very sensitive to response conflict for it in terms of whether or not it's an English word or not, but the other areas there was still stimulus based conflict. The fact that there are two main meanings and two pronunciations. That was the case in both experiments.
Dr Marie-Josee Bisson
But you saw a difference between those particular words that are words in English and Dutch compared to control words that are just English words. So the fact that a word could also be a word in Dutch, it required the brain to do something extra, basically.
Dr Walter Van Heuven
Indeed.
Dr Marie-Josee Bisson
Even if it led to the same answer, the fact that, you know, the brain reacted in the way like kind of a warning bell. Two languages here, which one do you want? Well, yes. So this sort of. Yeah.
Dr Walter Van Heuven
Yeah, there's still there's still this conflict because there's there's information in terms of two meanings theres information of two pronunciations. And it means that the brain is, even though you tell it's not relevant for the decision, it's in itself. The brain activates this information automatically and it's, it's something you can't really control. There's a lot of other evidence suggesting that you can't really prevent this from happening. And also, it's in a sense quite good, of course, because if you if you restrict yourself to only one language, it means that if somebody starts talking to you in another language, you wouldn't understand this person, which is a bit off.
Dr Marie-Josee Bisson
Yeah, no, it's really interesting and obviously it's really good that we have this this mechanism that helps us control which language is for the right situation. And I wanted to ask you, because I for myself personally, I find that if I've been speaking in English for so long and then suddenly I do want to speak French, but it's like the cognitive control because it stopped the French for so long suddenly I do want it to come out, but it's difficult. Obviously I can do it, but it's a bit more. It feels like it's not fluent and it requires almost more effort to speak my native language.
Dr Walter Van Heuven
Yeah, that's a that's a really interesting phenomena. And I think a lot of people have that experience that and that it then becomes very difficult to to suddenly switch to another language. And I think the important thing here is that it's that this has to do that it's speaking, which is very different from the research in terms of reading and processing written words. And I think in speaking, of course, you have this very you need this control very much. And so that's where the control really can prevent other representations too, to become active. And certainly over a longer time, you would expect that this mechanism has some influence, although you can still probably find effects of the the other language and it's just more difficult. The other aspect there is, of course, when you're speaking one language and you don't speak the other language for a long time, the representation itself also kind of gradually become less active as a whole. That means it takes a bit of time to reactivate those representations. So that's kind of two aspects I think that that play a role in this kind of phenomenon people have experienced. Yeah.
Dr Marie-Josee Bisson
It's really interesting. And of course, we didn't have time to much talk about how we talked about bilinguals. Well, you know, people at the end of the language learning journey. But what happens as you start to learn another language, obviously these mechanisms have to come into place straight away, like automatically, obviously. And with children as well, as children they grew up hearing two languages. You know, we're saying today, you know, we've got this strong cognitive control mechanism. They're not going to be confused. They're going to know very, you know, quickly and automatically which language is appropriate for which situation because of this cognitive control.
Dr Walter Van Heuven
Exactly. Yeah. I think children picked it up very quickly in terms of what other languages people are speaking. And a bilingual child will detect that immediately. And when the person cannot speak the other language, they will just focus on that language that the person understands.
Dr Marie-Josee Bisson
Brilliant. So before we finish, is there one thing that you'd like people to remember from today's episode?
Dr Walter Van Heuven
I think I think that its just an important thing to realise that the brain is not neatly organised in terms of.
Dr Marie-Josee Bisson
We don't have tidy boxes in out brain.
Dr Walter Van Heuven
There are no tidy boxes there. It's all integrated. It's one system, one language system. And of course in that language system there is some information as to what language that particular word belongs.
Dr Marie-Josee Bisson
Yeah.
Dr Walter Van Heuven
Because that's relevant when you speak. So that information is definitely there. And the other thing is that when you are practising one language or you're reading one language, it's not a case that you're restricting yourself to that language. It's still the case that it's possible candidates, possible words in both languages are always activated and so they can influence this process of reading words, for example.
Dr Marie-Josee Bisson
Yeah. So that's amazing. You know, our languages are intermixed. All the words are intermixed. There is some sort of tag that, you know, tells us what language each word is in, but they're all mixed in together in one big pot, and it's definitely not separate. We know that's now from the research. So that's, I think, really interesting for people to know. And also the fact that both of your languages are active at the same time to the level of right before you start to speak or the output. And of course, it can influence some of the process. From what you've said to us in your research project, you did it at the level of just reading. So they were very active and we saw you explain how that slowed down some of the responses, for example, but also with the brain imaging as well, how that was represented. But when we speak as well, you know, both both languages are activated all the way to the end, then that's how you get those speech errors and then these intrusions. So this has been a really fantastic episode. I feel like we've touched on so many different things. So thank you so much, Walter, for joining us today. It's been a pleasure to have you. Now, in the next podcast, we will be talking to Dr. Jiayi Wang about pragmatics in language, learning, what they are and why they're important. To find more information about this topic or about our podcast, please visit our web page languagescientists.dmu.ac.uk. This is where you can go to ask questions, to leave comments, or even to take part in some of our current research. We'd love to hear from you. Thank you for listening and thank you for De Montfort University for funding this series of the podcast. I'm Dr. Marie-Josee Bisson and you've been listening to the Language Scientists podcast.
