When it comes to understanding speech, the world’s top tech companies are still playing catch-up with children.
Daniel Swingley, an associate professor of psychology in the School of Arts & Sciences and director of the Penn Infant Language Center says, “Systems like Siri are good, but they’re not anywhere near as good as a five-year-old. How could it be that kids learn to interpret the speech sounds of their language so easily when engineers who are trying to get computer systems to do the same thing took more than 40 years to get where we are now?”
The Infant Language Center is dedicated to uncovering how infants and toddlers come to understand how their language works. This tricky problem is made more difficult by the fact that a good deal of this learning takes place before children have enough language to express what they know or what they are thinking.
“For a long time, most of what we knew about language acquisition came from studying children who had already begun to talk,” Swingley says. “Kids show amazing intricacies of development when they start to say their first words. But there’s a lot that’s going on underground before that. What we are trying to do is figure out what the youngest infants know, how they learn, and how that learning leads to the enormous strides children make in the first couple of years.”
Most studies in the Center involve observing how infants respond to spoken words, often by tracking their eye movements. Even before they can readily say them, infants can demonstrate that they know words by looking at or touching an object. This type of research has already shown that infants may start learning words much sooner than previously believed, grasping some common nouns as early as 6 months.
One study, featuring very young infants, will help determine just what it is about teaching environments that allow children to intuit the meaning of more abstract words. Words for concepts such as “all gone,” take longer to learn than words for simple objects like “apple” or “spoon,” but infants begin to acquire them before their first birthday. This is quite a feat given that such words do not have an obvious referent a parent can point to, and words for actions, such as “dance,” may refer to a wide range of activities that can all look quite different from one another.
Another experiment, conducted with children who are beginning to speak, will investigate how they begin to distinguish similar-sounding words. At first, toddlers seem to treat similar-sounding words, like “bell” and “ball,” as meaning the same thing. Eventually, though, they learn that this difference in sound signals a difference in meaning, while at the same time learning that people with different-sounding voices can say the same word in different ways.