Autism spectrum disorder (ASD) is widely recognized as a complex, heterogeneous neurodevelopmental condition that affects about one in 54 individuals (Center for Disease Control, 2020). According to the 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5; American Psychological Association; 2013), individuals with ASD have impairments in social communication and interaction, and they produce restricted and repetitive behaviors. Regarding social interaction, impairments in pragmatic speech appear across different language levels and ages along the autism spectrum (e.g., Baird & Borbury, 2016; Lam & Yeung, 2012; Tager-Flusberg et al., 2005; Volden et al., 2009). The present study focuses on the pragmatic speech produced during conversation. Conversational interactions require a range of pragmatic skills such as turn-taking, topic initiation, and topic maintenance (Ninio & Snow, 1996; Wetherby, 2006).
Previous research has reported deficits in conversational turn-taking and maintaining topics during conversation in children with ASD who were verbal (Landa et al., 1992; Tager-Flusberg & Anderson, 1991). Specifically, compared to children without ASD, these children were found to have difficulties in expanding conversational topics, maintaining appropriate and relevant topics, and engaging in turn-taking, thus resulting in little reciprocal conversation (Bauminger-Zviely & Agam-Ben-Artzi, 2014; Capps, Kehres, & Sigman, 1998; Jones & Schwartz, 2009; Lam & Yeung, 2012; Losh & Capps, 2003). These deficits persist when these children become adolescents (e.g., Adams, Green, Gilchrist, & Cox, 2002; Koning & Magill-Evans, 2001; Paul, Orlovski, Marcinko, & Volkmar, 2009; Philofsky, Fidler, & Hepburn, 2007). Of these studies, Paul et al. (2009) identified three major pragmatic difficulties: topic management, quantity and type of information provided, and reciprocity.
However, the development of conversation skills is understudied and the findings to date are inconclusive. In one of the few studies undertaken, Hale and Tager-Flusberg (2005) tested 57 children with high-functioning ASD (average IQ = 77) at two time points over a year, observing conversations with their parents. These children were found to have made significant improvement in their ability to maintain a topic of discourse and to present a significant reduction in imitation of their parents’ speech. In a recent study by DiStefano, Shih, Kaiser, Landa, and Kasari (2016), 55 children with low-functioning ASD and minimal verbal skills participated in an intervention program in one of two joint engagement-based intervention conditions. Children in both conditions showed improvement in the length and frequency of their communication interchanges over the course of the intervention. On the contrary, Tager-Flusberg and Anderson (1991) found that children diagnosed with ASD did not show any developmental change in discourse ability over a year. However, only six children participated in their study. Given the heterogeneity of language abilities in autism, it is difficult to detect developmental change in such a small group of children.
Besides the inconclusive findings on the developmental changes of conversation skills, the aforementioned studies focused on English-speaking children with autism and none of them examined the conversational skills of Chinese-speaking children with autism or documented the growth of these skills over time. According to the Education Bureau in Hong Kong, the number of students recently diagnosed with ASD was 7,200 in 2015/16, 8,600 in 2016/17, and 10,300 in 2017/18, representing a 20% rise each year. With such a large number of young children diagnosed with ASD, it is crucial to understand their language and communication impairments, particularly deficits in conversation.
As a result, the first objective of the present study was to document the growth of conversational skills in Chinese-speaking preschool children with autism over nine months at four time points. Changes were modeled over time. In this study, we collected naturalistic language samples from parent-child dyads. Naturalistic language samples carry detailed language information regarding children’s initiation of conversation, appropriate responses to the parents, and their maintenance of conversation (DiStefano et al., 2016).
Parents provide “around the clock” intervention for children with autism (Koegel, Koegel, Frea, & Smith, 1995), even though many receive regular interventions from outside the family. Therefore, besides characterizing the conversational skills of Chinese-speaking children with autism over time, we investigated whether parents’ verbal responsiveness and redirectives in a conversation would elicit children’s appropriate responses and then increase the number of conversation turns. Parents’ verbal responsiveness refers to the utterances that follow the child’s focus of attention, actions, and communications (Yoder & Warren, 1999; Landry et al., 2000; Siller & Sigman, 2002; McDuffie & Yoder, 2010). Parents’ redirectives refer to the utterances that require the child to stop attending to the event, object, or person with which they are engaged and attend to something else (McCathren, Yoder, & Warren, 1995).
Since the 70s and 80s, researchers have suggested parents or therapists adopt a child-oriented or scaffolded approach when interacting with children with developmental disabilities (Bruner, 1978; Nelson, 1989). Under this approach, parents should follow the child’s lead, respond to, and expand or recast the child’s initiations while keeping the meaning of the child’s utterances in order to foster their children’s verbal participation. Previous findings have shown that children with developmental delay or developmental disabilities are more likely to converse on the topics that were continued by their parents on the immediately preceding topic of children’s interests than the topics initiated by the parents (Yoder & Davies, 1990; Yoder, Davies, & Bishop, 1992). Besides expansion and recast, questions asked by parents may elicit children’s continuations too. In an experiment conducted by Yoder and colleagues, an adult experimenter interacted with children with developmental delay using two different styles – topic-continuing wh-questions and topic-continuing comments (Yoder, Davies, Bishop, & Munson, 1994). Their findings showed that topic-continuing wh-questions are more likely than comments to elicit child continuations.
Adults’ or parents’ verbal responsiveness can elicit further children conversation for a few reasons. First, the child may be interested in maintaining an interaction about a topic they had previously shown interest in (Olsen-Fulero & Conforti, 1983). Based on this view, the child is more likely to maintain an established topic when confronted with an adult utterance that maintains the child’s topic than when the adult initiates a new topic. Second, it may be easier for the child to understand adult speech that continues the established topics and attentional lead, which results in less information processing load (Bloom, Rocissano, & Hood, 1976; Landry & Chapieski, 1989).
However, the aforementioned studies, which investigated the influence of parents’ verbal responsiveness on children’s participation in a conversation, only examined children with developmental delays (especially those with Down Syndrome). To date, no study has examined children with ASD. Nevertheless, it is crucial to understand whether parents’ verbal responsiveness would facilitate the elicitation of appropriate responses in these children who are found to show deficits in responding to their parents in a conversation. If so, therapists can recommend scaffolding strategies for developing conversation skills to parents of children with ASD.
Having said that, a few studies have reported that parents’ verbal responsiveness facilitates their children’s play behaviors and joint attention. A study by Bottema-Beutel and colleagues examined 98 parent-child dyads (Bottema-Beutel et al., 2018a) of which 50 were young children with ASD and their parents, and 48 were toddlers with typical development and their parents, with the children in both groups having a mental age of 13 months. Their study found that child toy play was more likely to elicit follow-in utterances (utterances that relate to the child’s attentional focus) from the parents of children with ASD than from those of children with typical development. In turn, these follow-in utterances had a facilitative effect on the functional play of children with ASD, whereas caregiver-focused utterances had an inhibitory effect. A later study by Bottema-Beutel and colleagues also found that parents’ follow-in utterances elicited supported joint engagement in both young children with ASD and typical development, with strong association in children with ASD (Bottema-Beutel, Lloyd, Watson, & Yoder, 2018b). In contrast with follow-in utterances, redirectives are negatively related to joint attention as the child is required to shift the focus of attention and follow the adult’s need in order to establish joint attention with the adult (Landry & Chapiesky, 1989).
Abundant research also reported the positive influence of parents’ verbal responsiveness on language development in children with ASD (e.g., Bottema-Beutel, Yoder, Hochman, & Watson, 2014; Dimitrova, Özçalıskan, & Adamson, 2015; McDuffie & Yoder, 2010; Haebig et al., 2013; see reviews in Edmunds, Kover, & Stone, 2019). McDuffie and Yoder (2010) categorized verbal responsiveness into follow-in comments (‘utterances that follow the child’s focus of attention and describe what the child is looking at or playing with, without conveying the expectation that the child do something different or respond verbally to the parent’) and follow-in directives (‘utterances that follow the child’s current focus of attention and convey a request for the child to change some aspect of his/her play with toys or to provide a verbal response’) (p. 1032). In their study, they followed preschoolers with autism over six months and measured the vocabulary they produced in play episodes at two time points. They found that parent follow-in comments and follow-in directives at baseline significantly predicted children’s vocabulary use six months later. Similarly, Haebig, McDuffie, and Weismer (2013a, 2013b) found that follow-in directives are positively associated with language comprehension and production a year later in children who were minimally verbal or verbally fluent, while follow-in comments have the same facilitating effect only in children who were minimally verbal. Siller and Sigman (2002, 2008) even found that follow-in comments could predict gains in language skills 10 and 16 years later in children with autism. In contrast with follow-in comments or directives, relatively less is known about how parents’ redirectives influence language development in children with ASD. Besides, the relationship between redirectives and language development for typically developing children and children with developmental delays is either negative or non-significant (Crawley & Spiker, 1983; Harris, 1994; Tomasello & Farrar, 1986).
Taken together, previous research has shown parents’ verbal responsiveness has positive impact on the elicitation of contingent play and joint attention behaviors and even on long-term language development in children with ASD. However, no study to date has examined the influence of parents’ verbal responsiveness and redirectives in these children’s participation in a conversation. Specifically, would children with ASD be more likely to elicit appropriate responses under parents’ verbal responsiveness than under parents’ redirectives? The second objective of the present study addressed this question. Based on the findings of the previous studies that showed the positive influence of parents’ verbal responsiveness in children’s behaviors and language skills, we hypothesized that parents’ verbal responsiveness would positively predict the proportion of appropriate responses from their children and hence the number of conversational turns. In contrast, redirectives would negatively predict appropriate responses and conversational turns in their children.