Orthography Facilitates Vocabulary Learning for (Some) Children with Autism Spectrum Disorders (ASD)

Background:  Research has demonstrated that exposure to orthography facilitates oral vocabulary learning for typically developing (TD) children (Ricketts et al, 2009, 2011; Rosenthal & Ehri, 2008).  To date there is no evidence that children with Autism Spectrum Disorders (ASD) use print to support learning but children with ASD are often exposed to pictures accompanied by words to support their communication.

Objectives:  This study investigated whether children with ASD can use orthography to facilitate oral vocabulary learning and explicitly explored the influence of language and reading ability.   It was hypothesised that children with ASD and age-appropriate structural language skills (ALN) would learn new vocabulary as efficiently as their TD peers, effectively using orthography to assist their learning.  Contrastingly the ASD language impaired children (ALI) would experience less benefit from orthography due to their poorer reading skills and the proportion of fixations on the orthography (as opposed to the picture) would be smaller than their TD and ALN peers. 

Methods: Participants were 55 children age 8-12 years; 30 who had a formal diagnosis of ASD (ALN n=15, ALI n=15) and 25 TD peers.  Participants were taught 16 low frequency concrete science words, for example ‘breccia’.  For half of the stimuli, the written word was presented alongside a picture of the target item (orthography present, OP); the remaining items were taught with orthography absent (OA).  Eye-tracking attained fixation information during the learning phrase.  Learning was assessed via three post-tests: picture naming, spoken word to picture matching and two-alternative-forced-choice spoken word to written word matching.  Accuracy and response time (RT, for correct responses only) were recorded. 

Results: The eye-tracking data indicated that during presentation of OP stimuli in the learning phrase, all three groups fixated on the picture more than the word.  However, the ALI group had a larger proportion of fixations on the written word than the TD or ALN groups.  With regards to the post-tests, picture naming accuracy was significantly greater for OP than OA stimuli and greater on day 2 than day 1 for all three groups.  For the spoken word to picture and spoken word to written word matching tasks there was a main effect of orthography and of group.  The facilitation of orthography was significant for the TD and ALN groups but not for their ALI peers, who were less accurate and had slower RT than the TD and ALN participants. 

Conclusions: These results indicate that orthography facilitates vocabulary learning for ALN children, as it does for their TD peers.  This suggests that the teaching of new oral vocabulary would benefit from the written form of the word being provided.  ALI children did not benefit as extensively from the presence of orthography.  However, the proportion of fixations on the written form was greater than expected, potentially indicating that despite their reading difficulties the ALI children were attempting to utilise the written form to augment their learning.