"Not By The Chair of My Hinny Hin Hin": Young Kids' Slips of The Tongue Show Mechanism For Language Similar to Adults

BUFFALO, N.Y. -- We all laugh when young children make speech errors, or slips of the tongue: when a two-year-old says, "Her run is nosing," instead of "Her nose is running." Or when an impatient three-year-old, waiting for her mother to finish a task, says, "Mom, when are you going to be dead? I mean, done?"

Yet, it's these kinds of errors (additional examples on last page) that suggest that the basic mechanisms for language production are in place at a very early age and in a form that is similar to that of an adult, a University at Buffalo linguist says.

Once children start making slips of the tongue, usually from about 18 months of age, they show nearly the same language behavior as adults, notes Jeri Jaeger, UB assistant professor of linguistics, who has put together the largest existing corpus of children's speech errors.

Jaeger's research, which has been published in the Journal of Child Language and Language and Speech, is one of the first studies that has been able to document children's mental mechanisms for organizing and producing speech.

While adult speech errors have been studied extensively for the information they provide about the processes involved in the mental organization and on-line production of language, little research has been done on children's slips of the tongue, Jaeger says. One reason is that a researcher must be very familiar with a child's grammar in order to be sure that what sounds like a slip of the tongue to an adult is, in fact, a violation of the child's current rules of production.

"It took a parent linguist collecting data daily to do this," she says.

Jaeger has collected a total of 1,300 speech errors from her three children and from 35 other children she observed in a day-care center. All of the children were between the ages of 18 months and 6 years when the slips were collected. She recorded the other children's slips of the tongue to verify that the kinds of speech errors her children were making were not idiosyncratic to children with linguist parents. She found no differences between the data collected from her children when compared to the other children.

Jaeger notes that adults go through several "stages" when organizing what they want to say. First, they think about the concept they want to express. Secondly, they pick out the nouns, verbs and other grammar they need to use. Then they assign an intonation pattern. Finally, they string the words in the right order and decide how to pronounce them.

"It's a very complicated and involved process," Jaeger says. "But are kids doing the same thing? Or do they have a simplified process? And if they do, how does it match up with adults' cognitive processes?"

She compared the slips of the tongue she recorded for the children with the types of speech errors made by adults, and found that children make most of the same types and proportions of slips as adults. The most common errors in both children and adults are phonological -- sound-based -- errors. These easily outnumber lexical -- vocabulary-based -- errors and phrase-based errors.

Among the phonological errors, children, like adults, make more substitutions (such as "hoo hard" for "too hard"), than additions ("I want clean plants" for "clean pants"), omissions ("me ad" for "me mad"), movements ("my ummy taches" for "my tummy aches"), or reversals ("shool schoes" for "school shoes").

Furthermore, as with adult errors, children's errors show that there is a phonetic organization to the mental storage of speech sounds. Sounds that are more similar in pronunciation to each other -- such as "P" and "B" -- are more likely to be substituted for, or exchanged with, each other than sounds that are very different in pronunciation, such as "P" and L."

Errors made by adults at any of the various stages of speech production do not disrupt any of the other stages, Jaeger says, noting that these stages operate independently. "When adults make a speech error, everything else (in the speech production process) works fine. Each stage functions on its own and feeds into the next stage."

And that holds true for children, she adds.

"As in adult slips of the tongue, when there is an error in one level, all other levels (of children's speech production) function normally," she says.

"The striking similarities between children's and adults' slips of the tongue suggest that the basic mechanisms for language processing may be in place at a very early age, in a form not much different from that of a mature language processor."