The Contribution of Language Ability and Linguistic Factors to Disfluency in Bilingual Children

Speech disfluencies are common in individuals who do not stutter, with estimates suggesting a typical rate of six per 100 words. Factors such as language ability, processing load, planning difficulty, and communication strategy influence disfluency. Recent work has indicated that bilinguals may produce more disfluencies than monolinguals, but the factors underlying disfluency in bilingual children are poorly understood.

We investigated the child, lexical, and syntactic factors associated with disfluencies in bilingual children who do not stutter during parent-child interactions. Forty-four Spanish-English bilingual parent-child dyads engaged in a play-based interaction. The children were 4-6 years old (M = 62.3 months, SD = 6.96; 19 boys, range: 48.0-71.0). Children's language abilities ranged from clinically low (i.e., with a developmental language disorder) to typical.

Analyses revealed that children were more disfluent when they produced longer utterances. There was also a tendency for children with lower language skills to produce more disfluencies than children with higher language skills, when producing longer utterances. However, the mean lexical frequency of each utterance, the language of the utterance, and the child's language dominance were not associated with children's disfluency.

These findings inform psycholinguistic models of fluent speech production and indicate that in bilingual children who do not stutter, disfluency is largely a reflection of utterance length. Children's overall language ability rather than language dominance was a more important contributor to disfluency in spontaneous speech. These findings have implications for assessment of bilingual children and for considerations of factors that may support or hinder disfluency in bilingual children who do and do not stutter.