Does Being Japanese-English Bilingual Affect Language Development in Children with Autism?

Background: Many educators and clinicians believe that bilingualism has negative influences on language development of children with Autism Spectrum Disorders (ASD). However, there have been few studies conducted to examine whether or not, or how bilingualism affects the language development of children with ASD. There is not sufficient evidence to prove that the aforementioned claim is true. On the other hand, past studies on typically developing bilingual children have indicated that bilingualism can lead to linguistic and cognitive benefits. It is therefore important to research further on this topic. In this preliminary study, we focused on Japanese-English bilingual children, both typically developing and with ASD. With the advancement in globalization, the number of children with ASD growing up in bilingual environments is gradually increasing in Japan, and this population has not been revealed in research. 

Objectives:  To explore vocabulary and grammatical abilities of high functioning Japanese-English bilingual children with ASD (BLASD) in both languages and to compare results with those of typically developing Japanese-English bilingual children (BLTD).

Methods:  Participants were six high functioning BLASD children (MA=104.5 months, 1 female) and 6 BLTD children (MA=105.8 months, 2 females). All were born and raised in a Japanese-English bilingual environment since birth. All children in the BLTD were living in US. Of the BLASD, 5 children were raised in Japan and one was raised in US. The following standardized tests were used to assess the language abilities among participants: PPVT-4 for English vocabulary comprehension, EVT-2 for English vocabulary production, Trog-2 for English grammatical comprehension, PVT-R (Picture Vocabulary Test-Revised) for Japanese vocabulary comprehension, and J-COSS3 (Japanese test for Comprehension of Syntax and Semantics) for Japanese grammatical comprehension.

Results:  PPVT-4: Mean Standard Score (SS) of BLTD was about average while SS of BLASD was 2SD below average (SS=106.2, SS=70.8; respectively). EVT-2: SS of BLTD was about average, while SS of BLASD was 1SD below average (SS=103.5, SS=83.7; respectively).  PVT-R: Mean age equivalent of BLTD was 73.8 months, while it was 96.7 months in BLASD.Trog-2: SS of BLTD was 89.4 and SS of BLASD was 84.0. J-COSS3: Of the BLTD, three children were at level 3 (5-6 year old level), two were at level 2 (3-4 year old level), and one child was at level 4 (6-7 year old level). Compared to the BLTD, BLASD showed relatively high levels. Three children reached level 6 (above 8 year old level), and one child at levels 3, 4, and 7, respectively. However, spondaic developmental pattern was found among all BLASD children.

Conclusions:  BLASD demonstrated higher abilities in Japanese vocabulary comprehension than BLTD, while BLTD showed higher abilities in English vocabulary comprehension and expression than BLASD. These results indicate the possibility that vocabulary development more affected by the language spoken in their community. Regarding English grammatical comprehension, no difference was found between groups. It was also noteworthy that BLASD demonstrated an atypical pattern in Japanese grammatical comprehension, in contrast to BLTD. ASD and linguistic environment might have different influences on vocabulary and grammatical development.