Do Children with ASD Use Imitation to Acquire Negation Markers?

Background:  

Children with ASD have been reported to use echolalia, where they imitate others’ utterances without fully understanding their structure or meaning (Gerenser, 2009). To what extent does this or other kinds of imitation help them acquire grammar? Some research has found that children with ASD use more complex negation and question forms prior to using the less complex forms (Eigsti et al., 2007; Hoff, 2009), although others have reported that children with ASD do not produce more complex forms first in imitated utterances (Tager-Flusberg & Calkins, 1990). No studies have yet directly compared children’s development of negation markers with their caregivers’ usage. By hypothesis, if children are learning via imitation, their early usage of negation should follow their caregivers’ patterns of usage quite closely. 

Objectives:  

We investigate the acquisition of negation markers in children with ASD and TD children, comparing their usage with that of their caregivers.

Methods:  

We included 11 TD toddlers (MA = 19.86 months at Visit 1, 9 males), and 10 children with ASD (MA=32.83 months at Visit 1, 8 males); the groups were matched on the CDI (ASD=92.6; TD=118.27) and Mullen VR (ASD=27.8, TD=24.45) at Visit 1. At 6 visits each 4 months apart, children engaged in 30-minute, semi-structured play sessions with their parents, which were transcribed and coded for all utterances that included any morphosyntactic negation marker (e.g., no, not, none, can’t, don’t, doesn’t, won’t, isn’t, aren’t, wasn’t). Data from visits 1 and 2 are reported here.

Results:  

At visits 1 and 2, most of the negation markers in both groups of children were “no” (In the TD group, 99% at visit 1 and 85% at visit 2; in the ASD group, 85% at visit 1 and 80% at visit 2).  Uses of “not” and “don’t” increased at visit 2 in both child groups (TD: 7% don’t, 3% not; ASD: 10% don’t, 3% not); the groups did not differ at either visit. In contrast, the caregivers’ usage of negation markers was much more diverse, including 41%-43% no, 16-19% not, 21%-26% don’t, 2-3% can’t, 4% didn’t, 1-2% isn’t, and 1% won’t. Chi-square tests revealed that the distribution of negation marker frequency differed significantly between the adults and children (TD: X²=11.13, p<.001; ASD: X²=7.94, p=.0048).

 

Conclusions:  

Children with ASD’s use of negation markers was not different from TD children’s usage; in contrast, both groups differed significantly from their caregivers’ patterns of use.  These findings suggest that both TD children and those with ASD are not learning negation markers by simply imitating their caregivers, but are instead analyzing their morphosyntactic input selectively. Future analyses will examine the children’s usage through visit 6, to determine whether the children with ASD increase in the complexity of negation structures in the same pattern as TD children, as well as whether the ASD children are using their negation markers with the same meanings as TD children (e.g., as denials, rejections, commands, assertions).