Semantic richness and word learning in children with autism spectrum disorder

Abstract

Semantically rich learning contexts facilitate semantic, phonological, and articulatory aspects of word learning in children with typical development (TD). However, because children with autism spectrum disorder (ASD) show differences at each of these processing levels, it is unclear whether they will benefit from semantic cues in the same manner as their typical peers. The goal of this study was to track how the inclusion of rich, sparse, or no semantic cues influences semantic, phonological, and articulatory aspects of word learning in children with ASD and TD over time. Twenty-four school-aged children (12 in each group), matched on expressive vocabulary, participated in an extended word learning paradigm. Performance on five measures of learning (referent identification, confrontation naming, defining, phonetic accuracy, and speech motor stability) were tracked across three sessions approximately one week apart to assess the influence of semantic richness on extended learning. Results indicate that children with ASD benefit from semantically rich learning contexts similarly to their peers with TD; however, one key difference between the two groups emerged - the children with ASD showed heightened shifts in speech motor stability. These findings offer insights into common learning mechanisms in children with ASD and TD, as well as pointing to a potentially distinct speech motor learning trajectory in children with ASD, providing a window into the emergence of stereotypic vocalizations in these children.

Figure 1

IRED placement.

Figure 2

Example nonsense image.

Figure 3

Visual referents paired with the novel phonetic strings that attained word status.

Figure 4

Illustration of the Spatiotemporal Index (STI). The top panel shows 10 non-normalized productions from a child with ASD producing the novel word /bʌpkəv/. The middle panel shows the same productions now time- and amplitude normalized. The bottom panel shows the standard deviations obtained across the same productions and the resulting STI.

Figure 5

Change in speech motor stability by condition collapsed across groups. Larger difference scores indicate enhanced stability. Error bars show standard error.

Figure 6

Overall speech motor stability between the two groups collapsed across pre- and post-tests and sessions. Error bars represent standard error.

Figure 7

The degree of change in speech motor stability from pre- to post-test (i.e., difference scores) for both groups. Error bars indicate standard error.