It's Mine, . . . It's Mine: Unsolicited Repetitions Are Reduced in Toddlers.

A phenomenon called "repetition reduction" can increase articulation rate in adults by facilitating phonetic and motor processes, which indicates flexibility in the control of articulation rate. Young children, who speak much slower, may not have the same speech motor flexibility resulting in the absence of the repetition reduction effect. In this study, we tested whether spontaneous repetitions of young children are produced with a faster articulation rate than their original utterances. Twelve monolingual English-speaking children were observed at four time points between 2;0 and 3;0 years of age. A significant increase in articulation rate and syllable count was found using multilevel models for all utterances over the 1-year period. At each time point, however, the repeated utterances were produced significantly faster than the original utterances even though the content and syllable count differed minimally. Our findings conform to the pattern of adult studies suggesting that a "naturistic" form of repetition reduction is already present in the speech of children at 2;0 years. Although certain aspects of speech motor control are undergoing rapid development, existing motor capability at 2;0 already supports flexible changes in articulation rate including repetition reduction.