ASD-Sibs Show Differences In Initiating Behavioral Requests at 12 Months

Background: Children with Autism Spectrum Disorders (ASDs) demonstrate difficulties with nonverbal referential communication, or communication with a social partner about their environment. Two aspects of nonverbal referential communication, initiating joint attention (IJA; sharing enjoyment with another about an object or event) and initiating behavioral requests (IBR; eliciting help from another) are lower in the younger siblings of children diagnosed with ASDs (ASD-Sibs) than in the infant siblings of children with no ASD (COMP-Sibs). The current study examined IJA and IBR in ASD-Sibs compared to COMP-sibs at 12 months of age, an age at which behavioral markers of ASD-related difficulties may become more observable (Rogers, 2009), with both an examiner and the infant’s caregiver. This may help us better understand early nonverbal communication abilities across different social contexts in infants at-risk for developing an ASD.

Objectives: 1) Examine associations of referential communication (IJA and IBR) between a semi-structured examiner-administered and a relatively naturalistic parent-child measure). 2) Examine group differences in IJA and IBR on both measures.

Methods: Two measures of nonverbal referential communication were administered to 53 infants (ASD-Sibs n=37, COMP-Sibs n=16). The Early Social Communication Scales (ESCS; Mundy et al., 2003) is a 15-20 minute semi-structured interaction between an infant and an examiner in which the examiner presents objects individually to the infant. The Assessment of Referential Communication (ARC) is a 6 minute semi-naturalistic floor play between the infant and caregiver in which toys are placed within reach of the infant and the caregiver is instructed to respond briefly to their infants’ referential bids and refrain from initiating any interaction with their infant. The ARC provides a measure of infant-initiated nonverbal referential communication with a caregiver, furthering our understanding of the impact of social environment on infant referential communication. IBR during the ARC was dichotomized, such that a score of zero indicated no IBR during the ARC, and a score of one indicated at least one instance of IBR during the ARC.

Results: Both IJA, r(53)=.29, p<.05, and IBR, r(53)=.35, p<.05, were positively associated between the ESCS and ARC. Significantly fewer ASD-Sibs (16%; 6 of 37) demonstrated IBR during the ARC than COMP-Sibs (44%; 7 of 16), χ²(1, n = 53) = 4.57, p < .05. While all infants initiated at least one behavioral request during the ESCS, ASD-Sibs engaged in IBR significantly less frequently (rate-per-minute M=.94, SD=.70) than COMP-Sibs (rate-per-minute M=1.47, SD=.85), F(1, 53)=5.87, p<.05. No significant group difference was found in frequency of IJA demonstrated during the ARC or the ESCS.

Conclusions: There were robust differences in IBR across two measures of referential communication that employed different adult partners and levels of adult structuring. This replicates previous studies’ findings of IBR differences at 12 months of age in ASD-Sibs, and expands the finding to different social contexts, suggesting that differences in behavioral requesting may be a robust early signal of a differing developmental trajectory within this at-risk group.