Abstract
<p style="margin-right: 0px; margin-bottom: 0px; margin-left: 0px; text-indent: 18px; font-stretch: normal; font-size: 12px; line-height: normal; font-family: "Times New Roman";">The quantity and quality of children’s early language input from adults in the preschool classroom are likely predictors of children’s language outcomes. Using big behavioral data garnered from automated measurement techniques, we examined the quantity, quality, and temporality of vocalizations occurring in preschool classrooms and their relation to language abilities. Vocalization data were collected using LENA audio recorders over 34 observations in three oral language inclusion classrooms for children with hearing loss between 2.5 and 3.5 years of age (N=29, 14 Hispanic). The mean phonemic diversity of vocalizations was employed as a measure of the quality of classroom speech. Receptive and expressive language abilities were measured at the end of the school year using the Preschool Language Scales (PLS-5). As hearing experience (time with proficient hearing [from birth or aided hearing]) increased, children produced more frequent, longer, and more phonemically diverse vocalizations. The frequency, phonemic diversity, and temporality of adult speech positively predicted the frequency, phonemic diversity, and temporality of child speech, respectively. Children who produced more phonemically diverse vocalizations exhibited higher end-of-year language abilities, even when controlling for hearing experience. Mediation analyses indicated that the phonemic diversity of children’s language production mediated the effect of children’s language input on their receptive and expressive language abilities. These findings suggest that qualitatively richer language experiences strengthen children’s verbal production abilities, which in turn are associated with language outcomes. In sum, the phonemic diversity of children’s vocalizations emerged as a promising correlate of developing language capacities and target for individualized intervention.</p>