“I might speak differently to you than I would speak to someone else,” Isabell Wartenburger says. This is how the Professor of Patholinguistics/Neurocognition of Language summarizes one of her current research projects. Since she is aware that a journalist cannot make much of her professional jargon, she uses other terms and adjusts herself to her conversation partner – she changes her perspective. But what does that mean for her brain? How much brainpower is required to react to various communicative situations? A project at the University of Potsdam applies different methods to research such processes in children and adults. “Experimental Pragmatics” (XPRAG) comprises 16 projects scattered throughout Germany that focus on the use and meaning of language. This research association is being funded by the German Research Foundation (DFG).
In the Potsdam sub-project led by Prof. Dr. Barbara Höhle and Isabell Wartenburger, three postdocs are studying how the awareness of a conversational partner’s knowledge influences his or her own understanding of language. Since October 2014, several tests have been done to establish how the new perspective is assumed. In a way, they are playing “I spy with my little eye…” with their study participants.
Maria Richter is one of these postdocs and explains the setup: “According to our experimental design, the experimental participant plays a communication computer game with an avatar, i.e. an artificial person, as a conversational partner. The participant and the avatar face each other virtually and look at a mostly empty shelf. Some of the shelves contain an object. The avatar asks the participant to move a certain object with a mouse click.” The interesting thing is that some shelves are covered on one side so that the participant can see them, but the avatar cannot. This creates a conflict: While the avatar sees just two objects of a kind, the participant sees three. So if the avatar asks the participant, for instance, to move the little sheep to the top, the participant has to consider that the avatar does not have the same knowledge: The participant sees three sheep of various sizes, while the avatar can see only two. Since the smallest sheep in the eyes of the participant is not visible to the avatar, the participant has to suppress the impulse to choose this one and move the medium-sized sheep instead. This means the respondent has to take on the perspective of the avatar and click on the medium-sized sheep.
Can one’s egocentric view be shut out so easily, and if so, when exactly does this happen? And how much brain activity is required to ignore the little sheep that cannot be seen by the avatar? For how long and when exactly does the little sheep play a role in the subject’s brain? All this is made visible through an electroencephalograph (EEG), which registers the brainwaves throughout the processing time.
Maria Richter joined the XPRAG team in March 2015 and brings a lot of experience in recording and evaluating neuroscientific data by EEG. Together with associated postdoc Lu Zhang, she has researched what happens in the brain when we communicate with someone and this communication can succeed only by adopting the point of view, or perspective, of the other person. “Our work is based on the finding that a speaker provides only as much information as is required, from his or her point of view, to be understood – not more than necessary. Consequently, the speaker has to speculate about what the conversation partner already knows, i.e. their common ground. Besides, both the speaker and the listener may possess knowledge their counterpart is unaware of. It may result from a privileged position and is therefore referred to as privileged knowledge.” If the speaker does not correct a knowledge conflict, communication may be hampered, Maria Richter underlines. “We try to simulate this communicative situation in a number of computer experiments and monitor the subjects’ EEG,” her colleague Lu Zhang adds.
The experiment of the Potsdam linguists is just one of many pieces of the “experimental pragmatics” puzzle. Once pieced together, they will help to understand how the brain processes language and how quickly we can take on another’s perspective. “We have evaluated the reactions of between 20 and 25 adults,” Isabell Wartenburger says.
Similar tests are being conducted with children to find out how and when children learn that their own perspective does not always fall in line with that of the speaker and how they integrate this knowledge into their linguistic communication. The test design for studying children differs in that they are not placed in front of a computer, but in front of a real shelf with stuffed animals. Their reactions help us to understand at what age children are able to change perspective and what mistakes they make. In an eye-tracking study, postdoc Choonkyu Lee records and analyzes the eye movements of four and five year olds. “We use a grid with many shelves. On the one side, some shelves are closed. Then a doll gives the children tasks like ‘Grab the little sheep!’ We record the children’s eye movements to establish how quickly and precisely the right object is identified in a situation where the doll cannot see the smallest sheep, making the mid-sized sheep the correct one to grab,” Choonkyu Lee explains. The evaluation will show whether and how quickly children of a certain age are able to take another’s perspective.
According to Isabell Wartenburger, the experiments do not have an immediate practical benefit, but are invaluable to pragmatics research and could be of great importance for the future development of therapeutic approaches or for the linguistic interaction between human beings and computers. “Especially when it comes to children, it is very interesting to figure out at what age they are able to abstract from their own perspective and understand that the knowledge, ideas, and feelings of others differ from theirs – and adjust to it,” the psychologist underlines. Based on the EEG and the eye-tracking method, the Potsdam linguists want to establish a model for determining when and how fast we can change perspective and say “I spy with my little eye – and see what you see, too“.
Prof. Barbara Höhle studied linguistics at the Technische Universität (Berlin) and earned her doctoral
degree and habilitation at the Freie Universität Berlin. Since 2005 she has been Professor for
Psycholinguistics/ Language Acquisition at the University of Potsdam.
Contact
Universität Potsdam
Department für Linguistik
Karl-Liebknecht-Str. 24–25, 14467 Potsdam
E-Mail: barbara.hoehleuuni-potsdampde
Prof. Isabell Wartenburger studied psychology in Bielefeld, earned her doctoral degree at the Charité Berlin and was an Endowed Junior Professor with tenure track at the University of Potsdam. Since 2013 she has been Professor of Patholinguistics/ Neurocognition of Language at the University of Potsdam.
Contact
E-Mail: isabell.wartenburgeruuni-potsdampde
Maria Richter was a student of patholinguistics at the University of Potsdam and became a doctoral student at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig in 2011. In March 2015 she joined the XPRAG team.
Dr. Choonkyu Lee studied linguistics and psychology at the University of Southern California in Los Angeles (USA) as well as psychology at Rutgers University New Brunswick (USA) where he completed his PhD in 2012. He worked as a postdoc at the Utrecht Institute of Linguistics in Utrecht (Netherlands) before joining the XPRAG team as a postdoc in October 2014.
Dr. Lu Zhang acquired an M.Sc. in Language Science and Technology at Saarland University. In 2009 she became a doctoral student at the University of Bielefeld. In 2013 she took up a postdoc position at the Berlin School of Mind and Brain, and in the summer of 2014 she joined the XPRAG team as an associated postdoc.
Text: Heidi Jäger, Translation: Monika Wilke
Online-Editing: Agnes Bressa
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