Monthly Spotlight / VERDONSCHOT, Rinus
A fascination for language production
I am a researcher in the field of experimental psycholinguistics (EPL). The textbook definition of EPL is that it experimentally investigates the psychological and neurobiological factors that underlie the capacity for language in humans. However, what does that actually mean? It means that, of course, researchers studying EPL are interested in language. However, language is not only studied from a linguistic point of view, but EPL also considers the behavior of people and the associated brain patterns with that behavior. In short, EPL is linguistics mixed with experimental psychology and cognitive neuroscience.
In EPL, there are four main divisions: language acquisition, comprehension, production, and bilingualism. Language acquisition is the study on how babies and children learn language. Language comprehension is about how one can understand and read language. I work mostly on language production, particularly I am investigating how people produce speech sounds.
Figure 1: Language production
For instance, let’s say you have the intention to say the word “tiger”. Something happens in your brain (some planning), and eventually you say a “tiger” (“overt” speech). This happens really fast, even as fast as half a second. I am mostly interested in the planning part, so what happens between thinking (Intention) and saying something (Speech).
How can we speak?
The most prevalent model currently in the language production literature is the model by Levelt, Roelofs and Meyer (1999).
Figure 2: Language production model (Levelt, Roelofs and Meyer (1999))
According to this model, there are three major phases. The first phase is in the conceptual level. One knows about tigers, because this information is stored somewhere in your brain. Actually, most people don’t realize that the brain is always changing. For instance, if one sees a person for the first time many things are stored about that person. So, when one would see that same person again somewhere one would realize “Ah, I know this person”, because the brain has stored particular information about that person (such as length, face, hair, etc.). This is called a concept of something, and one can “activate” concepts by thoughts or by seeing/hearing things.
Secondly, what one does when producing a word is to access syntactic information for that word. For instance, the word, “tiger”, is noun, and it is countable. In some languages, like German, syntactic gender is also activated (i.e. “tiger” takes the masculine form which is important later when syntactically agreeing with other words). The brain considers all these factors, however, importantly due to automatic spreading of activation (which is a kind of electricity in a network) and other, closely related words, get activated too. So in the “tiger” case, not only tiger but also lion becomes strongly activated, and maybe even a turtle (but to a lesser extent as it is not a dangerous animal like tiger or lion).
It needs to be mentioned here that a word receiving activation is different from being selected. According to this model, one can only say one word one time (but see Roelofs, 2008). One of the words receiving activated has to be selected and if more words are activated it becomes more difficult to choose the correct word.
Then, it is time to assemble the pronunciation of a word. In many European languages, such as English and German, this occurs in a phoneme-by-phoneme fashion. Other things will be added too, such as a stress, prosody, and pitch accent (in Japanese). For example, the word, “tiger”, would have been spelled out into phonemes, and also the metrical structure (two syllables with stress on the first) would be computed. Then these two pieces of information are combined together to form the word “taI-gər”. After that, a motor response will be prepared. This simply means the computation of how to move particular muscles, so that one is able to speak the word correctly. Most languages have a limited amount of syllables which one uses all the time, and the most prevalent ones are believed to be stored in a “syllabary”.
Figure 3: Three major phases of language production from the model of Levelt, Roelofs and Meyer (1999)
This steps form the basis of the Levelt et al. model. In short, we have the conceptual level, lexical-syntactic level, and the production of phonology. Like other fields of science, psycholinguistic models have to be informed and validated by experiments. Typically, two types of experiment are used: behavioral and brain experiments. As for the former, time and accuracy are measured, and as for the latter, this would be brain activity.
Practical study for our better life
Studying language processing can contribute to our society in many ways. First of all, language is one of the things, which truly separate us from other animals. Animals may have language capabilities to some degree, but we, humans, are unique in having this ability developed to this extent. Language is intertwined with thought and it is necessary to understand the mechanisms behind those processes as they form part of the core of what it is to be human.
From a more practical perspective, for people who have particular problems with aspects of language processing (e.g. speaking, comprehension, or reading) due to medical reasons or otherwise, it is important to know the brain mechanisms behind natural language processing mechanisms as strategies could be developed to better diagnose and tackle their problems.
In addition, we cannot ignore the importance of EPL in the today’s world, which is getting smaller as more people travel around. Actually, for both business and pleasure it helps to have good language skills and to know more about other languages. For instance, we might emphasize or better articulate certain sound combinations in our own language we know non-native speakers have difficulties with, or we might use a different way of saying based upon the language of the interlocutor.
I first got interested in this field of study when I happened to meet a professor, who later became my PhD supervisor, at a university event as I talked with him about linguistics and psychology. I came to Japan three years ago (on a Canon Foundation and a JSPS scholarship) and became an assistant professor at Waseda Institute for Advanced Study (WIAS) this April. I had investigated some properties of Japanese before joining WiAS. For instance, I did a lot of work on how Japanese people read Kanji. What I found was that in Japanese when processing kanji which have two (or more) pronunciations, such as 水 (/mizu/ and /sui/), that both pronunciations become activated in the brain even though just one of them was needed.
In WiAS, I am trying to study several new ways to investigate how people build phonology (speech sounds), in their native and second language. I also would like to find out how new technologies (such as KINECT) can be used in psycholinguistics. In addition, I am quite interested in bilinguals and especially how a good command of a second language influences processing in the first language.
Contribution to Japanese learners of English
I believe that EPL may contribute to understanding how Japanese people can better learn English pronunciation. Many Japanese learn English with katakana. This method may work well from a practical point of view if one wants to make learners understand English easily or make them motivated. But I doubt whether katakana is a good idea when it comes to speaking English. Actually, speaking English as this is the most important problem for Japanese learners of English. Reading and writing are typically pretty good. But speaking (as well as listening) still lag behind, and the result does not sound like English. That is may be due to the usage of katakana (e.g. the famous English movie “The Lord of The Rings” would be transcribed/pronounced as “ザ ロード オブ ザ リング” or “Za · Rōdo · Obu · Za · Ringu”…OMG!... in Japanese which contains many sounds different from the original). So, if learners are aware of some fundamental differences between English and Japanese, learning strategies could be changed, and I think EPL can assist in these matters.
協力：M.A Program in Journalism, Graduate school of Political Science, Waseda University