Researcher in Profile: Masoud Jasbi on Children’s Acquisition of Function Words

By Chia-wa Yeh, Head Teacher and Research Coordinator
Over the past three years, nearly 150 children at Bing have played a fun guessing game with Jazzy, a brightly colored hand puppet. For the game, children took one card at a time from a stack of cards. Each card pictured one or two animals. Jazzy’s job was to guess what was on the cards. Upon hearing Jazzy’s guesses such as “There’s a dog and a cat” or “There’s a dog or a cat,” children then told the puppeteer Masoud Jasbi whether the guesses were right.
But Jasbi was not an ordinary puppeteer. He was in fact a graduate student in linguistics at Stanford who recently received a doctorate. He brought Jazzy to life through his deft puppetry and animated voice with a big smile and a warm rapport with children. The game was designed to investigate children’s understanding of function words such as “and” and “or.”
What follows is an interview with Jasbi about his work.
Tell us about your early years.
I was born in Tehran, Iran, in 1988. Around that time, Tehran was being hit by missiles, but many children in my generation were lucky that in just a few months after I was born, the eight-year Iran-Iraq war ended. So I grew up in an era of hope and recovery. I went to the same all-boys school for 12 years (primary to high school), so I have many deep and lasting friendships from back then. My favorite hobby was sports, especially soccer.
Why did you decide to study language learning?
I was very interested in what makes us who we are. In the Iranian culture, like many Eastern cultures, knowing one’s self is considered the most important task in life. I think as a teenager I took that message a little too seriously. So I read a lot about the human mind and soon got fascinated by how unique and special language is to the human species. I thought the best way to understand us is to understand how we know and learn language. Since Iran did not have a degree in linguistics, I went to the University of Manchester to get my BA and then came to Stanford for my PhD. My PhD dissertation advisors are professors Eve Clark, Michael Frank, Ellen Markman and Chris Potts. 
What studies did you conduct at Bing? 
I studied children’s understanding of the function words “too,” “and” and “or.” My games are often structured as guessing games. For example, in one study, there were cards with pictures of animals on them (e.g., cat and dog), and a puppet named Jazzy guessed what animals were on the card without seeing them. Jazzy would say things like “cat and dog” or “cat or dog.” Children told us whether the guesses were right or not. This setup helps us know how they understand words like “and” and “or.” I found that by the age 4, children’s understanding of these words does not substantially differ from adults’. Given how abstract the meanings of these words are, this is an impressive achievement for children. 
What got you interested in children’s acquisition and understanding of function words such as “and” and “or”? 
Function words are very special. When we think of a word, we often think of words like “dog,” “chair,” “red” or “eat.” But language isn’t just made up of nouns and verbs. Tiny function words like “the,” “or” and “too” are present in nearly every sentence and make the backbone of language. They are like nuts and bolts that put pieces of language together. They let us create complex sentences and convey abstract thoughts. Without them, we cannot communicate as effectively as we do. Discovering how humans learn and understand function words  helps us understand the inner workings of human language and thought. 
What was your experience conducting studies at Bing like? 
Running studies at Bing is amazing for many reasons—the lovely staff and children as well as the beautiful school, to name a few. But perhaps the most important one for me was the environment. It is fair to say that the biggest challenge in developmental research is methodological: How can we best capture children’s knowledge and mental state? If children feel nervous or confused about what is going on in the study, we won’t be able to capture what we’d like to know about them. Rather, we collect noisy data, which are not useful to researchers. 
Bing creates the environment where our research feels like home to children. They are comfortable interacting with us researchers and they truly enjoy participating in the games that we design for them. In fact, they are so comfortable that they often comment on our games too. One time, a 4-year-old told me that my game will be a bit hard for 2-year-olds and if I want to study younger children I should make it simpler! I really appreciated how engaged and confident children felt when they participated in my games. This environment had a significant contribution to the success of my experimental studies. 
What’s your next step? 
I’m joining researchers at Harvard linguistics and psychology to continue my research on children’s understanding of logical words like “or” and “and.” The broader goal of the research there will be to understand how children represent and learn logical concepts and the words for them. 
Anything else you’d like to share? 
Jazzy the puppet has accepted a permanent position at Stanford to help the researchers who come to Bing. If you happen to see Jazzy around, don’t hesitate to say hi and ask about the new games!