Differences in Means-End Exploration Between Infants at Risk for Autism and Typically Developing Infants in the First 15 Months of Life

Background:   Means-end exploration has been well studied in typically developing infants between the first and second year of life. Infants are able to efficiently retrieve small toys from nested boxes through the use of advanced strategies that reflect improved bilateral hand use (transition from unilateral to bilateral hand use) as well as motor planning (the ability to perform movement sequences) (Goubet et al., 2006). Infants who later develop autism often show fine and gross motor delays within the first few years of life (Landa & Garrett-Mayer, 2005; Bhat et al., 2012). However, there has been no research to date that has examined means-end exploration tasks as early tools to determine autism-risk.

Objectives:   Therefore, the purpose of this study was to compare the means-end exploration abilities of infants at-risk (AR) for autism and typically developing (TD) infants between 9 and 15 months of age.

Methods: 16 AR infants and 16 TD infants were observed during a means-end exploration task at 9, 12, and 15 months with developmental follow-up and autism screening at 18 and 24 months. During each visit we collected video data on three tasks that involved retrieving a small toy sheep by – a) opening an opaque box, b) opening a transparent box, and c) opening two nested boxes. Dependent variables included time taken to complete each task, bilateral hand use, the number and variety of strategies used, number of attempts made, the amount of tester assistance provided, and the number of prompts provided.   

Results:   Our preliminary findings from a subset of infants suggest that TD infants dramatically reduced the amount of time taken to complete the task between 9 and 15 months. They also reduced the amount of assistance and prompts required to complete the task. They showed greater asymmetrical hand use and more advanced strategies to retrieve the toy. In contrast, AR infants showed greater task failure, longer times to complete the task, and immature exploration strategies such as greater unilateral hand use.

Conclusions: Our results suggest that means-end exploration tasks provide a window into the bilateral coordination and motor planning abilities of young infants, including those at-risk for autism. These contexts may provide an early marker for future risk of ASDs by the end of the first year of life. Moreover, these early bilateral coordination and motor planning delays may contribute to the social communication and cognitive delays of infants at risk for ASDs, specifically, in gestural communication, functional play, and problem solving abilities. Facilitating early means-end exploration would be an important learning context for infants at risk for ASDs.