Late talkers (LTs) are a heterogenous group of children who experience delayed language development in the absence of other known causes (Fisher, 2017). Many LTs “catch up” to their typically talking peers (TTs), but some go on to experience continued difficulties with speech and language development (Dale & Hayiou-Thomas, 2013), with little variance in long-term outcomes predicted by current language measures (Fisher, 2017). While typical language measures used in clinical practice and research with LTs involve broad-based language assessments, fine-grained measures of LTs’ language processing may elucidate mechanisms of early language delay and offer incremental utility in predicting later outcomes. In this dissertation, a group of TTs and LTs completed two eye-tracking experiments to assess two fine-grained aspects of language processing. Children were from U.S. monolingual English-speaking speaking families and the sample was mostly white and of higher socioeconomic status. In Study One, children completed a mispronunciation Looking-While-Listening (LWL) paradigm (Swingley & Aslin, 2000; White & Morgan, 2008). Children heard words that were pronounced correctly or contained a word-initial mispronunciation. Results revealed that both LTs and TTs were sensitive to these mispronunciations, but that LTs’ processing may have been more disrupted than that of TTs. These results suggest that, at least on word-initial phonemes, LTs have created accurate auditory-phonological representations. In Study Two, children completed a target-absent LWL paradigm (Chow et al., 2017; Huettig & McQueen, 2007) to assess children’s sensitivity to taxonomic semantic relationships. Results showed that both LTs and TTs were sensitive to the taxonomic relationships used in the experiment and looked to semantic competitors in the target-absent trials. Both groups also looked more to the target in the target-present condition than in the target-absent condition, suggesting both groups had formed specific, differentiated representations of these lexical items. Taken together, these results reveal both similarities and differences in how LTs and TTs process language. Future research should incorporate additional aspects of language processing, such as assessments of children’s motor-phonological representations, and include more diverse participants that are representative of the target population.

Creator

• Curtis, Philip Robert

DOI

• https://doi.org/10.21985/n2-7n5t-cf55

Subject

• Speech therapy
• Language
• Developmental psychology

Language

• en

Alternate Identifier

• http://dissertations.umi.com/northwestern:15574
• etdadmin_upload_819331

Keyword

• Phonology
• Semantics
• Language Delay
• Late Talker
• Language Development

Date created

• 2021-01-01

Resource type

• Dissertation

Rights statement

• In Copyright