Behaviour and Language Development in Infants at Risk for ASD: The Role of Early Attention Preferences and Early Language Development

The diagnostic criteria for Autism Spectrum Disorder (ASD) cluster around communicative, linguistic, and social deficits (DSM-IV; American Psychiatric Association, 1994). Identification of impairments associated with ASD relies on children’s explicit behaviours, which only emerge reliably after the first year of life (De Giacomo & Fombonne, 1998). Thus, data on earlier social attention, language development, and ASD behaviours in children with ASD are limited. In this dissertation, I examine how early perceptual biases and ASD-like behaviours relate to language skills in a high-risk cohort of infant siblings of children with ASD (SIBS-A) and a low-risk cohort of infants siblings of typically developing children (SIBS-TD). Chapter 2 investigates whether biases to infant-directed (ID) speech and faces differ between SIBS-A and infant siblings of typically developing children (SIBS-TD), and to what extent early differences may be predictive of language skills and risk group membership. In this study, we found that both infant groups preferred ID to adult-directed (AD) speech and preferred faces to checkerboards; however, the magnitude of the preference was smaller in SIBS-A. SIBS-TD demonstrated higher expressive vocabulary than SIBS-A at 18 months. Vocabulary size correlated with early speech preferences, suggesting that a preference for ID speech early in development may facilitate later expressive language. Finally, infants’ preference for faces contributed to determining group membership. Chapter 3 explores vocabulary development and ASD-related behaviours, and whether these skills are associated with one another and differ between high-risk and typically developing infants. Results from this study demonstrated that SIBS-A exhibited lower expressive vocabulary at 12 and 18 months as compared with SIBS-TD. SIBS-A additionally demonstrated significantly more ASD-like behaviours that were also more severe in nature at 18 months. Moreover, expressive and receptive vocabularies were significantly correlated with ASD behaviours. The findings of these studies suggest that infants at heightened risk of ASD differ from SIBS-TD in their preferences for ID speech and faces, as well as vocabulary skills and ASD behaviours early in childhood. These early linguistic and behavioural differences may underlie deficits in later language development and social communication and have important implications for research examining early detection measures for ASD.

Name thesis:degree_name

Doctor of Philosophy (PhD)

Discipline thesis:degree_discipline

Applied Psychology

Grantor dc:publisher.institution

Graduate Studies

Year dc:date.issued

2013

Author dc:creator

• Droucker, Danielle

Advisors dc:contributor.advisor

• Curtin, Suzanne
• Schwartz, Kelly

• Education--Early Childhood
• Psychology--Clinical
• Psychology--Developmental

Statement dc:rights

• University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.

Language dc:language.iso

eng

DOI

http://dx.doi.org/10.11575/PRISM/25103

OAI identifier oai:identifier

oai:ucalgary.scholaris.ca:11023/674