Air Date: Week of February 28, 2003

Host Laura Knoy talks with Gerald McRoberts, a psychologist at Lehigh University, who’s found men and women really differ when it comes to baby talk.

Transcript

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KNOY: It's not easy to decipher an infant's first words amid all the gurgles and gahs. There are even phrase books and dictionaries to help parents decode babyspeak. But what about the baby talk that moms and dads make? Gerald McRoberts, a psychologist at Lehigh University, joins me now to talk about his study on this question, published in the recent journal Speech Communications.

Professor McRoberts, welcome.

MCROBERTS: Hello, Laura.

KNOY: Professor McRoberts, why do we grownups use baby talk at all?

MCROBERTS: Well, clearly, very young infants don't understand the words of the language, so we use it partly because the babies like it. If you talk to a baby using the high-pitch and wide-pitch range that's common across the world in infant-directed speech, babies pay attention to you. If you start talking to them in a tone of voice that we're using, they very quickly turn away.

KNOY: Professor McRoberts, walk me through some of the baby talk sounds that you studied.

MCROBERTS: Well, we used a computer model to try to classify different types of expressions of emotion that parents typically use with their babies: praise, prohibition, and attention. We ignored the words and we took the acoustic properties, sort of the melody of each utterance.

For example, for praise you have a high-pitched expression that then sort of falls off slowly and is elongated. So a parent might say something like "Good boy" or even just "Yeah."

That contrasts very sharply with the way that we talk to babies when we want to prohibit their behavior. If you find a baby trying to stick its finger in an electrical socket, you're going to say something like, "No, stop, don't touch." And that's clearly very different. It causes the baby to stop what it's doing. Oftentimes, they sit down rather quickly, and sometimes they cry.

On the other hand, if the baby, especially a toddler, for example, has gotten a little ways away from a parent and the parent wants to call them back, they might say something like, "Bobby," or "Annie". What we found was that the computer model classified mothers' utterances correctly about 75 percent of the time, but it classified father's utterances correctly about 65 percent of the time.

KNOY: What do you think accounts for the differences between men and women when it comes to baby talk?

MCROBERTS: Certainly, cultural wisdom has it that women express emotions better than men do, and it's possible that they are clearer in that way. It's also possible that it was something as simple as the fact that our fathers were not as comfortable in our laboratory setting as the mothers were.

Finally, fathers tend to talk to their babies as if their babies were a little older or a little more developed than they really are. What that means is that they may be putting more of the expression into the words and less into the melody of their speech.

KNOY: Gerald McRoberts is a psychologist at Lehigh University. Professor McRoberts, thanks for talking with us.

MCROBERTS: Thank you for having me.