Context and language processing: a balanced story: an interview with Dr. René Terporten

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Dr. René Terporten was a PhD student at the Max Planck Institute for Psycholinguistics. He defended his thesis entitled ‘The Power of Context: How linguistic contextual information shapes brain dynamics during sentence processing’ on October 2 2020.

1. What was the main question in your dissertation?
For my dissertation I asked the question: How does context influence the way we process language? Think for example of the following situation, I will provide you with a couple of sentences and you have to guess what this is all about: ‘Every morning I do the same, I need to open it, I fill it up and then press it. It will buzz and grind until it decides to have finished. I cannot go without it and still it leaves a bitter taste.’ Without any context or background information these sentences remain rather cryptic or at least vague. Yet, if I tell you that the context is about making coffee, the described routine becomes crystal clear. Not only will you be able to interpret these sentences easily, but you would also be able to predict what will happen next. The context does something to the way we interpret and predict language. I was particularly interested in how context influences language processing in the human brain.

René Terporten
2. Can you explain the (theoretical) background a bit more?
The idea that context influences the way we process language is not new. A quick check at the scientific literature reveals the many views and angles by which researchers studied context. There are commonalities between all these different perspectives and in my work I went a step further from the common approaches. First of all, researchers have tended to focus on very specific contextual situations.They took a specific topic, like movement or other actions, and created a context within this topic. For example, participants were asked to read sentences that described the use of boxing gloves or the action of cycling. This way, researchers showed that the brain activates regions that support movement or movement perception, whenever a language context is processed that is also about movement. In my work I was not interested in specific topics or context situations. Instead I asked how the details provided by context in general influence our brain while we process language.

Second, the research so far compared contexts that are rather extreme. This means that they compared a context that was very rich in information, to a context that remained vague and provided no detailed information at all. In such a scenario, participants were, for example, either reading sentences like “Because of its rotating blades, the helicopter stays up in the air”, or “Because of its moving parts, the machine stays up in the air”, with the former example being very rich and specific in information and the latter example remaining vague. It is helpful to look at extreme situations to capture the boundaries of the influence of context. Yet, this is not a typical situation we encounter in our daily lives, in which it is more likely to face a context that in terms of richness of details lies somewhere in the middle of these two extremes. This is why, in my work, I not only looked at the extreme ends of context information, but I also included context situations that fit in-between. I thus looked at a lot of contextual topics to cover the general influence of it onto language processing, and I also included contexts that gradually differ in the richness of information that they provide.

3. Why is it important to answer this question?
I think it is a very fundamental question to ask which factors influence how our brain deals with language. But beyond that, what I think is fascinating is how dynamically and quickly our brain adapts to different contexts. For example, as soon as we enter a library, we know that, in this context, we should remain quiet. As soon as we enter the party of a good friend, we know that in this context we should do the exact opposite. This seemingly happens on the fly and is not only restricted to language processing. But if it happens during language processing it appears to happen even faster! With my work I captured parts of these fast dynamics and I showed how our brain adapts to a context in language on a moment to moment basis.

4. Can you tell us about one particular project?
In my first project, participants read sentences on a screen, word-by-word. These sentences differed in the degree to which they provided detailed information of a context. The more details a sentence context provided, the easier it was for the participants to anticipate what specific words are likely to come up next. At the same time, it was easier to link a word with its previous context, if the information provided by this context was rich enough. An example of a sentence with a rich context would look like this: “The guitarist replaced one of his strings” As a participant you would read this sentence word-by-word. The idea is that you already predict that this is about ‘strings’ as soon as you read “The guitarist replaced […]”. This would be an example of a detailed sentence context. On the other hand, a sentence like “The man replaced […]” would not provide information that is rich enough to lead to the prediction of the word ‘strings’. As a participant in this experiment you would read a lot of sentences like these and they would all differ gradually in their richness of contextual detail. At the same time, I was recording brain activity and I looked at brain processes, while participants were reading through these sentences.

5. What was your most interesting/ important finding?
With this approach I showed that our brain is remarkably sensitive to the changes in a sentence’s context. Even though the sentences and their details about the context were quite simple, our brain still detects the small changes in context richness and immediately adapts. Interestingly though, the brain did not adapt in the way I thought it would. Remember, we used sentences that gradually differed in the richness of details that their context provided. Thus, there were sentences with only a very vague context, and sentences that made the context more and more detailed. I expected that as the contexts in the sentences became richer, that the brain would be more and more involved in language processing. Yet, what I saw was that actually the brain was most involved for sentence contexts that, in terms of detail richness, were somewhere around the middle, whereas for very rich sentence contexts the brain was less involved. What was happening here? Why would the brain be less involved in language processing when it can make use of a very rich language context?

I found the answer lied in the type of brain regions that are recruited during the processing of these different contexts. Instead of the typical brain regions that are commonly found for language processing, the brain regions that generally indicate how difficult and demanding a task is became active. Thus it seems that the more rich details a context provides, the easier it gets to process language in this context. On the other hand, if a context only provides vague to no information at all, then there is little information to process, which is not very demanding for our brains. Contextual information that is somewhere around the middle in terms of richness contains enough information to be processed, but because the information is not very detailed, it is a quite demanding process for our brain.

6. What are the consequences/ implications of this finding? How does this push science or society forward?
The findings I provided help future research to be aware of the fact that comparing only the extreme ends of contextual information during language processing can be misleading. Instead language science can benefit from using experimental designs in which the richness of contextual information is changed gradually. Next to that, my project should lead to the awareness that slight changes in language context do not only have consequences for brain areas that support language processing. Also other brain areas that might often be linked to attention, memory or the demands put onto the brain as a whole are affected by it. Future research could therefore make use of this awareness and focus on the interaction between these different brain areas as the richness of contextual information changes.

7. What do you want to do next?
During my PhD I focused a lot on sentence reading. Up next I want to go beyond the sentence level and focus on longer texts, or narrative stories. Narratives are interesting because along their story line the narrative context can flexibly change. For instance, while one paragraph in a narrative can be about events happening in a library, in the next paragraph the scene or the context could change to an event description of a rock concert. These overall changes in context in turn influence on how the individual sentences can be understood. I want to investigate how the human brain deals with the contextual information obtained from narrative stories.

 

Read more
Link to dissertation

 

Interviewer: Merel Wolf
Editor: Julia Egger
Dutch translation: Ava Creemers
German translation: Ronny Bujok
Final editing: Merel Wolf