Every parent remembers the thrill of hearing their child utter his or her first word and the jumble of words that soon follows.

Letitia Naigles, an associate professor of psychology, is exploring the process by which young children learn words and acquire language.

In a series of ongoing studies, Naigles is examining how children learn verbs. Those parts of speech are considered the most critical part of language, she says.

In a study being conducted with Edith Bavin from La Trobe University in Melbourne, Australia, Naigles is attempting to determine whether children will understand that a verb used in one kind of sentence can also be used in other kinds of sentences. Naigles says she and Bavin are trying to find out when children become able to use language creatively or in ways they haven't specifically heard, the way adults can.

To conduct the study, the two researchers created a series of verbs that children learn by playing with toys. The children use a seesaw which either squishes, or as Naigles says "lorps," a ball or knocks it back and forth, which Naigles refers to as "krazzes." The action is then described in one of two kinds of sentences, such as "The seesaw is lorping the ball" or "The ball is lorping."

Once the children learn the verb, the researchers try to determine if they can extend it and use it in a new frame that's different from the one they learned. The method allows them to look at toddlers' comprehension instead of their production. To do so, the children are told to watch two TV screens side by side, each of which shows one of the actions. An audio recording directs the children to look at the screen showing a specified action, such as an animal "lorping" the ball, and the researchers watch to see if the children look at the correct screen. If the children are flexible, they should be able to match verb and action, even if the sentence is different from what they had heard before. The researchers expect that children who are two and two-and-a-half years old will be able to do so.

In a second study being conducted with Erika Hoff, a psychology professor at Florida Atlantic University, Naigles is looking at the beginnings of conventional English verb use. Preliminary results indicate that verbs used in a variety of sentence types are the ones children learn the fastest, Naigles says. In addition, early data suggest that children are able to use the same verb in different ways. The researchers are currently tracking the first 10 verbs a child uses.

A third study explores the manner in which children learn verbs that express mental actions such as "think," "guess" and "know." By the age of three or four, children tend to use these verbs properly, Naigles says. More detailed studies of their comprehension, however, show that their knowledge still has some gaps.

In the study, children observe a conversation between two puppets in which they use mental verbs to describe their certainty about where an object is located. One puppet will say it "knows" the ball is in the green box, for example, while the second puppet will say it "thinks" the ball is in the yellow box. The child must decide where the object is, based on what the puppets say. The study is intended to discover when three- and four-year-old children understand the different degrees of certainty expressed by different mental verbs, and how they learn this.

Naigles also is investigating how much environmental influences such as attending preschool can account for the developmental change that children show between three and four years of age in understanding mental verbs. Naigles says most of the research involving mental verbs has only included children who attend preschool. In her study, Naigles will include a group of non-preschool attendees and compare the input they receive from their parents to the input preschoolers receive from their teachers.

Naigles joined the UConn faculty in 1998. She received her bachelor's degree in cognitive science from Brown University and her Ph.D. in psychology from the University of Pennsylvania.

Allison Thompson