Do children with autism spectrum disorders show a shape bias in word learning?

Abstract

Many children with autism spectrum disorders (ASD) acquire a sizeable lexicon. However, these children also seem to understand and/or store the meanings of words differently from typically developing children. One of the mechanisms that helps typically developing children learn novel words is the shape bias, in which the referent of a noun is mapped onto the shape of an object, rather than onto its color, texture, or size. We hypothesized that children with Autistic Disorder would show reduced or absent shape bias. Using the Intermodal Preferential Looking Paradigm (IPL), we compared the performance of young children with ASD and typically developing children (TYP), across four time points, in their use of shape bias. Neither group showed a shape bias at Visit 1, when half of the children in both groups produced fewer than 50 count nouns. Only the TYP group showed a shape bias at Visits 2, 3, and 4. According to growth curve analyses, the rate of increase in the shape bias scores over time was significant for the TYP children. The fact that the TYP group showed a shape bias at 24 months of age, whereas children with ASD did not demonstrate a shape bias despite a sizeable vocabulary, supports a dissociation between vocabulary size and principles governing acquisition in ASD children from early in language development.

Lexical composition in children with autism spectrum disorder (ASD)

“…In contrast to Swenson et al (2007), Tek, Jaffery, Fein and Naigles (2008) found differences between fourteen children with ASD (aged 2;2 to 3;1) and fifteen typically developing language-matched children (1;6 to 1;11) when intermodal preferential looking was measured during four visits over twelve months. The two groups did not differ in noun bias, consistent with Swenson et al (2007), but they did differ in their tendency to show a shape bias (i.e.…”

“…The literature on lexical development in children with ASD raises the same issue. The 'delay' view is supported by the ways lexical development in children with ASD resembles typical lexical development, namely that children with ASD (a) tend to acquire more words in their lexicons as they get older (Charman et al, 2003 ;Smith et al, 2007) ; (b) vary widely in lexicon size (Charman et al, 2003 ;Ellis Weismer et al, 2010 ;Ellis Weismer et al, 2011 ;Luyster et al, 2007 ;Luyster et al, 2008); (c) show a predominance of nouns and roughly the same percentages of nouns, verbs and closed-class terms as typically developing children with similar vocabulary sizes (Charman et al, 2003); (d) exhibit a noun bias in laboratory preferential looking studies (Swenson et al, 2007 ;Tek et al, 2008) ; and (e) manifest high correlations between parent-reported vocabulary scores and directly administered expressive language tests (Ellis Weismer et al, 2010 ;Luyster et al, 2008). On the other hand, the 'deviance ' view is supported by the ways in which lexical development in children with ASD differs from typical development, such as (a) a much higher percentage of severe vocabulary delays (Charman et al, 2003, Ellis Weismer et al, 2011Luyster et al, 2007 ;Luyster et al, 2008) ; (b) much greater variation in rate of vocabulary growth over time (Smith et al, 2007) ; (c) weaker associations between lexicon size and grammatical complexity than late talkers with the same-size lexicons (Ellis Weismer et al, 2011) ; failure to show a shape bias on novel word tasks (Tek et al, 2008).…”

Attentional Learning Helps Language Acquisition Take Shape for Atypically Developing Children, Not Just Children with Autism Spectrum Disorders

“…), prior to showing the shape bias. Indeed, this early noun vocabulary facilitates shape bias understanding (Samuelson 2002;Smith et al 2002;Tek et al 2008).…”

“…Bartolucci et al 1976;Eigsti and Bennetto 2009;Howlin 1984;Mitchell et al 2006;Van Meter et al 1997). A delay account would predict that children with ASD may eventually learn to use the shape bias heuristic, but not until they have more experience with objects (i.e.…”

Development of audience design in children with and without ASD.

“…Although subsequent research has shown that children aged around 4 or 5 (Nilsen & Graham, 2009), 5 or 6 (Bahtiyar & Küntay, 2008;Nadig & Sedivy, 2002) show sensitivity to the addressee's perspective in the production of contrastive adjectives, research has also shown that unlike adults, AUDIENCE DESIGN IN CHILDREN 6 words to novel referents like children without ASD (Tek, Jaffery, Fein, & Naigles, 2008) and use the same contextual information as their controls when doing so (De Marchena, Eigsti, Worek, Ono, & Snedeker, 2011;Preissler & Carey, 2005). When producing sentences, high-functioning children with ASD can also align sentence structures with their partner, demonstrating unimpaired syntactic representations (Allen, Haywood, Rajendran, & Branigan, 2010).…”