Publication Date



Open access

Degree Type


Degree Name

Master of Science (MS)


Psychology (Arts and Sciences)

Date of Defense


First Committee Member

Daniel M. Messinger

Second Committee Member

Jennifer S. Durocher

Third Committee Member

Jeffrey P. Brosco


Triadic attention, sharing attention with a person about an object or event, typically develops between eight and 12 months of age. This ability facilitates the development of social skills and language through shared exploration of objects and social stimuli. Two key aspects of triadic attention are initiating joint attention (IJA), the use of gaze and gestures to involve another in an experience, and behavioral requesting (IBR), the use of verbal and nonverbal communication to elicit help from another. Both aspects of triadic attention are impaired in individuals with Autism Spectrum Disorders (ASDs), which are characterized by social and communication deficits. The current study investigated the early development of triadic attention in eight- to- 12 month old infants who either have an older sibling diagnosed with an ASD (ASD-Sibs), or have older siblings with no ASD symptomatology (COMP-Sibs). This study examined age-related changes in the frequency of infant-initiated triadic attention using two measures, the Early Social Communication Scales (ESCS) and parent-administered Triadic Play Interaction (TPI). Triadic attention had modest associations between the TPI and the ESCS, with three of the six possible associations significant. At eight months of age, ASD-Sibs initiated significantly fewer IJA bids during the ESCS than COMP-Sibs. At 12 months of age, presence of IBR during the TPI differed significantly by group, with 18 percent of ASD-Sibs initiating a behavioral request, compared to 58 percent of COMP-Sibs. This study demonstrated that infant-initiated triadic attention behaviors differed by group status in both measures used, suggesting these measures offer different and complementary information regarding triadic attention behaviors in ASD-Sibs compared to COMP-Sibs. The use of the TPI in examining triadic attention development in ASD-Sibs is discussed.


ASD-Sibs; Trajectories In ASD-Sibs; Development Of ASD-Sibs; Infancy; Triadic Attention