Early Word Segmentation in Typically Developing Infants and Infants with Down Syndrome: A Preliminary Study

This paper presents some preliminary data from the first time point of a longitudinal study that is looking at precursors to language development in typically developing infants, and infants with Down syndrome. The skill of interest in this paper is speech segmentation ability, which refers to an infant’s ability to segment and recognise words embedded in fluent speech. Using the preferential listening paradigm, the study replicated findings from previous research, showing that typically developing infants are able to segment words with a strong/weak stress pattern by 10 months, but are not able to segment words with a weak/strong stress pattern. Group analysis suggests that at almost twice the chronological age of the typically developing infants in this study, infants with Down syndrome are able to successfully segment words with a strong/weak stress pattern, but are not yet able to successfully segment words with a weak/strong stress pattern. These results are discussed in relation to infants’ general cognitive ability. The finding that speech segmentation ability was not found to significantly correlate with general cognitive ability or concurrent language ability is also discussed.