9.6 Children Learning Syntax
Very young children are learning the grammar of their language very rapidly. Before they are able to produce much language (spoken or signed), comprehension experiments show us that babies already have some knowledge of syntactic categories and constituents.
Check Yourself
Video Script
In Chapter 5 we saw that babies start to learn the phonology of their first language very early — as soon as they’re born (and maybe even earlier than that!). What about syntax? What do babies and young children know about the syntax components of their grammar? And how can we tell?
Maybe we should start by thinking about what young children know about words. On average, children start to speak their first word around age one, and they start to combine two or more words some time after that, by about age one and a half. But if you’ve ever spent any time with young children, you know that they can understand a great deal more than they can say! Their comprehension is often much more advanced than their ability to produce spoken or signed words. But comprehension is much harder to observe. How can we tell what babies and toddlers understand about language?
One simple technique is called preferential looking. In this kind of experiment, researchers use a large screen or television. The baby or toddler sits strapped into a booster seat, facing the screen. The screen is split so that two different pictures appear, one on each side of the screen. While the pictures or are on the screen, a recorded voice speaks a sentence, maybe something like, “Look! Can you find the foot?” The idea is that if the baby understands the word foot, they’re going to look at the picture of the foot, not the picture of the banana. The researchers keep track of the direction of the baby’s head-turn, or they use eye-tracking to measure the baby’s eye movements. This kind of experiment has shown that babies pretty reliably look at the named object by about ten months, and even as young as six months, they’re looking at the named object more often than chance would predict. So at the age of six months, babies are already beginning to link up word forms with their meanings. What that means is that we can use this same preferential looking technique to figure out what kids know about syntax.
Instead of a picture of a single item, we could use the split screen to display two similar scenes. I’ve just put a simple picture here, but researchers often use short videos. The two scenes involve the same participants, but in different configurations. In the images here, the one on the left shows the adult chasing the kid, while on the right the kid is chasing the adult. The recorded sentence that plays, “Look! The kid is chasing the woman!” matches only one of the scenes. So if children look towards the matching scene, does that mean they know something about syntax? Or are they just paying attention to the word meanings?
Do you remember the idea of compositionality? It says tha