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Plays role in language development

RUNNING HEAD: Plays role in language development

In: Weisberg, D., Zosh, J., Hirsh-Pasek, K., Golinkoff, R.M. (2013). Talking it up Play, language development and the role of adult support. American Journal of Play. Special issue, 6, 39-54.

Talking it up: Play, language development, and the role of adult support

Deena Skolnick Weisberg (University of Pennsylvania)*

Jennifer M. Zosh (Penn State University, Brandywine)

Kathy Hirsh-Pasek (Temple University)

Roberta Michnick Golinkoff (University of Delaware)

*corresponding author

Department of Psychology, University of Pennsylvania

3720 Walnut St., Solomon Labs

Philadelphia, PA 19104

deena.weisberg@psych.upenn.edu

(215) 898-1712

To appear in American Journal of Play, special edition.

Abstract (word count = 116)

Play contexts facilitate childrens language learning. This review evaluates evidence for this claim, showing that play benefits childrens language development because playful environments incorporate many of the social-interactive and cognitive elements known to promote language growth. Although much of this evidence is correlational, a series of recent intervention studies offer evidence that a key variable relating play and language is the presence of adult support. In particular, guided play situations, in which adults scaffolding child-initiated learning, seem ideal for encouraging language development. Based on this argument, we conclude that understanding the efficacy of play for learning requires careful attention to the type of play and to the outcomes that result from these different types of play.

Talking it up: Play, language development, and the role of adult support

Play as a context for language development

Language is the currency of social interaction and school achievement. Thus, it is hardly surprising that thousands of pages have been devoted to understanding and encouraging optimal language acquisition in children (e.g., Clark, 2003; Clark & Clark, 1977; Dickinson, Griffith, Golinkoff, & Hirsh-Pasek, 2012; Frank, Goodman, & Tenenbaum, 2009; Golinkoff & Hirsh-Pasek, 1999; Golinkoff, et al., 2000; Harris, Golinkoff, & Hirsh-Pasek, 2011; Hoff & Naigles, 2002; Hollich, Hirsh-Pasek, & Golinkoff, 2000). Many of these investigations find that language thrives when children are interacting with adults and peers in a playful manner (e.g., Hirsh-Pasek & Golinkoff, 2003; P. Smith, 2010; Vygotsky, 1967; Zigler & Bishop-Josef, 2004), suggesting that play contexts can make important contributions to childrens language learning. Evaluating just how play might influence language, however, is a relatively new enterprise.

In a recent and influential paper, Lillard and her colleagues (2013) describe three categories of potential links between pretend play and other cognitive or social skills, including language, based on Smith (2010). The strongest potential link that one could posit is that play is a unique and crucial component in the development of cognitive or social outcomes, such that these outcomes would not develop without play. This causal view would claim that it is impossible for children to achieve, say, a certain kind of self-control if they do not engage in play; this skill would be impossible to acquire otherwise. An intermediate claim is that of equifinality: Play has a causal effect on the construct at hand, but is only one of many activities that can lead to gains in this outcome. In this case, play would lead children to develop self-control abilities, but other activities would do so equally well. The third and weakest claim holds that play has no role at all in the development of a given outcome but is merely an epiphenomenon or a byproduct of the learning situation. This would mean that play is involved in childrens achievement of the kind of self-control in question, but not because of anything intrinsic to the play situation. Rather, something involved in the play situation, such as increased social interaction, does the developmental work.

Although Lillard et al.s (2013) categories clearly delineate several possible relationships that play could have to cognition and in particular to language development, phrasing the options in such stark terms may inadvertently lead researchers to discount the more complex relationship that exists between these two skills. Put simply, asking whether play causes language development may be the wrong question. Instead, this paper rephrases the question to ask: What aspects of play contexts might promote language development? Under this framework, it becomes clear that play contains many of the ingredients that are necessary for optimal language growth, even though there may be no single element of play that does the majority of the work. Although this means that we must accept an equifinality view on Lillard et al.s (2013) account, this does not mean that plays role in language development is unimportant. To the contrary: Even if no single aspect of play is a necessary or sufficient condition for a particular language outcome, various aspects of play when taken in the aggregate link play and language.

In this paper, we review several lines of evidence showing connections between play and childrens language development. We use this evidence to suggest possible mechanisms whereby play contributes to language development.

An issue of definitions

As a prerequisite to thinking about links between the two constructs, it is imperative that we operationally define language and play. We begin by describing the kind of language that we will focus on in this paper, and then turn to the issue of defining play for the current purposes.

Languages are communicative systems that encode meaning through combinations of arbitrary symbols. Children acquire the rudiments of their language (or languages) by the age of 3. At that time, they can converse with strangers, make their desires and opinions clear, ask questions, and discuss the past and the future. There are many different aspects of language that we could discuss, but the current paper focuses specifically on vocabulary and grammar development. We will thus not explore the role of play in learning how to produce smaller linguistic structures, such as phonemes, nor larger structures, such as narratives (but see Ilgaz & Nicolopoulou, this issue). Children who establish the fundamentals of their vocabularies and syntactic skills in their early years are well equipped to enter school and to succeed socially and academically. Those who do not, such as a disproportionate number of children from lower socio-economic brackets, often fall behind (e.g., Dickinson & McCabe, 2003; Gershoff, 2003; Hart & Risley, 1995).

While linguists have provided relatively clear definitions of the characteristics of language, those working in the domain of play research still wrestle with how best to define this construct, which has blurry edges and takes many forms.

Play can refer to just about any activity that children do that meets a number of criteria and can range from wordplay (e.g., crib speech, childrens spontaneous riffing on phrases and making rhymes; Nelson, 2006; Weir, 1962) to worldplay (e.g., paracosms, elaborate and extended imaginary worlds created by a single child or group of children; see Root-Bernstein, 2013). In line with previous research (e.g., Burghardt, 2011; Fisher, Hirsh-Pasek, Golinkoff, Singer, & Berk, 2011; Garvey, 1990; Hirsh-Pasek, Golinkoff, Berk, & Singer, 2009; Hirsh-Pasek & Golinkoff, 2003; Johnson, Christie, & Yawkey, 1999; Pellegrini, 2009; Sutton-Smith, 2001), our definition of play emphasizes several specific features that can be used to distinguish play from other activities. First, play has no specific purpose and it is not linked to survival. Second, playful activities are often exaggerated such that an action done in pretense often takes longer or involves a wider range of motion than the same action done in reality. Finally, play is joyful and voluntary.

Our concern here is with language development, so in this paper we will focus on those types of play where we will be most likely to observe plays impact on language development. Specifically, we will consider only play in the early years, up to around age 6. Although both play and language develop past this point (see Roskos & Christie, 2001), play likely has its greatest impact when children learn the fundamentals of language. An additional limit on our current definition of play is that we will only consider instances of play that have some degree of sociality, because children are particularly likely to use and hear language when social partners are present.

Finally, we emphasize that play is child-led. While it is notoriously difficult to make a sharp delineation between play and other kinds of activities, a key way to distinguish between these two categories is by looking at who has the locus of control. In play, childrens interests determine how the interaction moves forward, not adults. This is a crucial distinguishing feature of play, and one of the main ways that can help us as researchers to determine whether a given interaction qualifies as play or as merely playful. This is also one of the features that characterizes guided play, which is a form of play wherein adults scaffold childrens active exploration in service of a learning goal (Fisher, Hirsh-Pasek, Golinkoff, Singer, & Berk, 2011; Hirsh-Pasek, Golinkoff, Berk, & Singer, 2009; Weisberg, Hirsh-Pasek, & Golinkoff, 2013b). In such situations, children are free to play and interact however they like, but a sensitive adult prepares the environment and joins in the play to help subtly respond to and guide children to focus on specific constructs. This situation still counts as play because the adults role is primarily to follow the childs lead. When the adults are in control, the situation is more like work dressed in play clothes --- what Bruckman (1999) termed chocolate covered broccoli. Such activities might be playful, and even fun, but they are not technically play.

Our definitions in place, we next ask: Do play contexts offer important support for language growth?

The role of play in early language development

Four characteristics of play potentially link play and language outcomes. First, many forms of play enlist symbolic thinking. In object-substitution pretense, for example, props are symbols that stand in for real objects, as in the classic banana-as-telephone scenario. This relationship between a prop and the object it represents is similar to the relationship that a word has to its referent. Because both play and linguistic communication share a representational character, play provides children with the opportunity to practice forming symbolic relationships (e.g., McCune, 1995; Miller & Almon, 2009; Piaget, 1962; Vygotsky 1967). Indeed, Tamis-LeMonda and Bornstein (1994) found that the frequency of symbolic play was related to childrens language comprehension at 13 months and to the diversity of a childs speech at 20 months. In a similar investigation, Laasko, Poikkeus, Eklund and Lyytinen (1999) observed solo symbolic play in 14-month-olds and found that childrens level of language comprehension was associated with their symbolic play competence at 18 months, as measured by a version of the Symbolic Play Test (SPT; Lowe & Costello, 1976). However, it could be that children who played more gained better language skills, or that children who had better language skills played more. Future studies should work to unravel the direction of these correlations. In addition, children can learn generic knowledge about animals from a symbolic pretend context. For example, when presented with a pretend scenario that illustrated one novel animals behavior, children readily generalized that behavior to new instances of that animal in real life (Sutherland & Friedman, 2012, in press). These studies suggest that the connection between play and language development may rely on the shared symbolic nature of both activities. Creating object-symbol relationships during play may allow children to practice distancing themselves from the here-and-now, preparing them to use words as abstract referential symbols. But this argument is still largely theoretical, and would benefit from studies focusing on whether and how play develops childrens symbolic understanding.

A second characteristic of play that may feed language development is the social interaction inherent in many play situations. In socio-dramatic play, children establish a play frame (e.g., going to the store) and collaborate to carry it out. Such situations often involve the need to negotiate roles and coordinate actions, which typically recruits the use of mental-state verbs (e.g., want, explain) (Pellegrini & Galda, 1990). Further, children often switch back and forth between speaking within the play frame (Can you give me some milk?) and providing commentary or stage directions (Im the baby; you be the mommy) (see Bretherton, 1989). These two factors --- taking on roles and negotiating --- point to aspects of social play situations that appear to encourage children to practice more advanced linguistic forms than they would use in non-play interactions. As Bruner wrote, the most complicated grammatical and pragmatic forms of language appear first in play activity (1983, p. 65). The evidence suggests that children are indeed more likely to use complex language in play situations than in non-play situations (Bergen & Mauer, 2000; Christie & Enz, 1992; Christie & Roskos, 2006; Singer, 1998), although future work should more carefully document such instances.

A third characteristic of play that contributes to language development concerns the sheer amount of language input available in many play situations. It is well known that the amount of language children hear is strongly related to their overall linguistic skills (e.g., Hart & Risley, 1995; Hoff, 2006; Hoff & Naigles, 2002; Hurtado, Marchman & Fernald, 2008; Tamis-LeMonda & Bornstein, 2002). Play with adults and peers bolsters language development because it encourages greater language use. For instance, the amount of talk children use with their peers during play in preschool is positively related to their vocabulary size in kindergarten (Dickinson & Moreton, 1991), as well as to measures of early literacy (see Roskos & Christie, this issue). Additionally, Dickinson and Tabors (2001) examined the relationship between talk during pretend play and language skills among low-SES children from 3 years of age through kindergarten. Increased amounts of talk during play with peers were associated with better comprehension and production. Indeed, a recent clinical report rightly advocates for the importance of play, especially for children of low-SES backgrounds (Milteer, Ginsburg, & Mulligan, 2012).

Finally, play might be important for language development because, when children are in control of an interaction, they are engaged: They produce and hear language about what they are particularly focused on. When talk refers to things that the child is concerned with, he or she does not have to switch attention from his or her own focus of interest to that of another. In line with this argument, a child is more likely to learn novel vocabulary items when an adult follows the childs interest as opposed to making the child to follow the adults interest (Dunham, Dunham, & Curwin, 1993). Even toddlers recognize the role of social cues in vocabulary learning. They only learn new words when a speaker is clearly labeling an object for their own benefit, and not when the speaker mentions the label outside of that kind of one-to-one interaction (Baldwin, Markman, Bill, Desjardins, Irwin, & Tidball, 1996). Thus, social play with other children and adults sets the child up to learn new words and sentence structures because the child is deeply involved in the common play scenario. A direct test of this claim should measure both childrens engagement and their degree of learning in play and non-play situations.

These are just four of many possible characteristics that could explain why play has been positively related to language development in the literature. However, the studies reviewed above, and many others that show associations between more play and more advanced language skills or larger vocabularies (see citations in Lillard et al., 2013, pg. 18 and Table 9), are largely correlational. It thus remains unclear whether playing causes children to develop better language skills, or whether children with better language skills play more, or whether a third variable is responsible for both better language skills and increased play. Indeed, some researchers have found that children with larger vocabularies are more likely to engage in symbolic play (L. Smith & Pereira, 2009), suggesting the reverse direction of causation from the one we describe above. The strongest case for plays contribution to language development thus comes from intervention studies.

Intervention studies of play and language development

Lillard et al.s (2013) review noted four intervention studies that directly examine links between play and language: Christakis, Zimmerman, and Garrison (2007), Levy, Schaefer and Phelps (1986); Lovinger, (1974); and Smilansky (1968), and there are other studies that address the same issue. In general, these studies increased the amount of play, by providing children with more time to play or with some play training, and reported subsequent increases in language. These studies bolster the claim above that play scenarios serve to facilitate language development. For example, Lovinger (1974) found that a group of 4-year-olds who engaged in one hour of pretend play every day for 25 weeks showed increases in language relative to a control group, who received no intervention. A similar study (Bellin & Singer, 2006) involved performing a video-based intervention with low-SES preschoolers. Parents, teachers, and other caretakers were provided with engaging video materials that instructed the participants how to guide a Magic Story Car through a number of activities to improve emergent literacy skills, such as phonemic awareness and letter recognition. A key part of this intervention was that children were not simply passively watching a program on TV. Rather, the video served as a spark to encourage beyond-the-screen activity. Following the video, caretakers and children created their own Magic Story Cars and engaged in pretend games about their own adventures. In just two weeks, children in the experimental group showed significant gains in vocabulary and emergent literacy skills compared to a control group.

These studies suggest that the presence of an adult partner in the play environment might be one key to explaining the relationship between language and play. For example, Christakis et al. (2007) distributed sets of plastic blocks and suggestions for how to play with them to families in their intervention group. The intervention was explicitly designed to encourage playful language interaction to spur childrens language growth. A control group of the same demographic did not receive block sets or instructions on play, hence these families were assumed to be carrying out their usual activities. Greater vocabulary growth resulted for the children in the intervention group than in the control group, as expected. This study, as well as those cited above, provides strong evidence that our third and fourth mechanisms --- increased input and child engagement --- can explain why play is linked to language growth. In addition, the absence of such playful interaction between parents and children might be responsible for low-SES childrens poorer language skills in comparison to middle class families.

Despite the fact that these studies appear to definitively demonstrate positive effects of play on language, they all suffered from methodological problems, most prominently the lack of proper controls. As Lillard et al. (2013) noted, the experimental (play) group in these studies was nearly always confounded with the presence of more adult attention. Children in the control groups sometimes received no intervention at all, let alone from an attentive adult partner. Adult attention and interactivity in any setting is likely a key variable in boosting childrens language skills. But some more recent and more carefully controlled studies show that play per se causes specific effects on language development, over and above effects of adult interaction. For example, Han, Moore, Vukelich, and Buell (2010) provided two groups of low-income children with a 30-minute didactic vocabulary-learning activity. This activity was essentially the same across groups, except that children in the play condition received a shortened version (20 minutes) as well as time to play (10 minutes). Unlike the studies reviewed above, this intervention was thus matched to the control in terms of amount of adult contact. Children in both groups made gains in their receptive vocabulary (i.e., words they understood), but only children who had played made gains in their expressive vocabulary (i.e., words they produced).

Other work also finds that play itself likely boosts language learning, sometimes by providing increased input and sometimes by increasing child engagement. Ferrera, Hirsh-Pasek, Newcombe, and Golinkoff (2011) showed that the type of play context matters for how much spatial language children hear, including terms like around, through, on top of, and under. These researchers compared the amount of spatial language produced when parents and children played with blocks. Both parents and children used more spatial language when they were in guided play contexts, where parents followed their childs lead while scaffolding the interaction, as compared to a free play context, where childrens play was allowed to roam wherever it would without any guidance. This study provides more evidence that interactivity, especially when it is sensitive to a childs own interests, is one of the key elements of play that helps children to learn language.

A similar study examined the impact of a play context on childrens understanding of the names and properties of geometric shapes. Fisher, Hirsh-Pasek, Newcombe, and Golinkoff (2013) studied preschoolers understanding of the meaning of a term like triangle. Children who learned in a guided play condition showed increased understanding and retention of this kind of spatial knowledge compared to children in both a free play condition and a didactic teaching condition. Importantly, children acquired richer geometric concepts in the guided play condition even though an adult was also present in the didactic play condition, showing that the effect was not due solely to the presence of a social partner. The effect of guided play was seen most dramatically when looking at childrens transfer: Children in guided play were much better at accepting unusual triangles (e.g., those with especially wide or narrow internal angles) as triangles.

These latter results suggest that certain characteristics of play may be more beneficial to learning than others. Most notably, guided play contexts seem optimal for achieving learning goals like language development. Crucially, adults in guided play conditions capitalize on teachable moments in the play context to support childrens learning. Language development can thrive particularly well in such settings, because children benefit from having an attentive and sensitive adult partner who talks about their focus of attention and follows their interests. Just as children in the guided play condition of Fisher et al. (2013) learned to appropriately extend geometric terms, perhaps children learning other types of new vocabulary would be able to show deeper understanding of word meanings when those meanings were acquired through guided play.

A large-scale in-progress intervention study (Dickinson et al., 2013) suggests that this may be the case. In this study, children enrolled in Head Start programs were taught new vocabulary words in the course of a book reading activity. They then engaged in a ten-minute play session with two peers, using replica objects that matched the main elements of the book (e.g., toy animals and tools accompanied a book about farming). The type of play varied by condition. Children in the free play condition could do anything they wished with the toys. Children in the directed play condition reenacted the story of the book, led by an experimenter who was following a script. This script contained definitions of and comments on a set of target vocabulary words. Importantly, this condition contained opportunities for children to engage in playful activities with the toys (e.g., Lets make the duck bring the cow back from the barn), but there were very few opportunities for children to express their preferences; the adult directed all of the play actions. Finally, children in the guided play condition engaged with the toys however they wished, as in the free play condition. But, unlike in the free play condition, the adult experimenter inserted questions into the play that supported the childrens themes and storylines while highlighting the meanings of the target vocabulary words. These questions were designed to take advantage of spontaneous moments in the play when childrens attention was focused on the meanings of the new words. For example, the experimenter might notice that a child was holding a cooking pot and use that as an opportunity to introduce and emphasize the target word scrumptious. These latter two conditions were matched for number of total exposures to the new words and their definitions.

Preliminary findings suggest that children learned the words better in the directed and guided play conditions than in the free play condition, as assessed by looking both at which words children understood (a receptive task) and which words they were able to define (an expressive task). These results are exciting because they suggest an alternative to merely drilling vocabulary words; play settings were successful in deepening childrens understanding of the new words. In addition, these results suggest that adult-supported play works best to focus childrens attention when there is a learning goal. Children learned the target vocabulary words significantly better than a matched set of words that were present in the book reading but never defined or included in the play. This shows that the adult-supported play conditions affected childrens learning above and beyond what could be explained on the basis of mere exposure to the words during the storybook reading.

This study also discovered an interesting difference in childrens levels of learning of the new words depending on their home environments. Specifically, although all children came from low-income backgrounds, the level of education between the mothers of these children varied. Children whose mothers were one standard deviation below the group mean in their level of education (i.e., they had less than a high school education on average) learned new words best in the directed play condition. In contrast, children whose mothers were one standard deviation above the group mean in level of education (i.e., they had at least one year of college or trade school) learned new words best in the guided play condition.

Why should the guided play condition, which relied on an adult following childrens lead, result in better learning for those from low-income homes in which mothers had higher levels of education? Children in this condition were given an unlimited opportunity to explore and follow their own interests during play. Perhaps guided play works better for children who have had greater opportunities to initiate storylines and use joint attention and adult support to scaffold those storylines. Mothers with a bit more education may engage their children in this kind of play. In contrast, children who came from homes with lower levels of education benefited from the increased structure and adult direction available in the directed play condition. Even if this analysis of the results is not entirely correct, these findings nevertheless illustrate that distinct forms of play may be differentially effective at promoting development, depending on who is doing the playing.

This preliminary finding may have important implications for educational practices designed to promote language development. The best possible environment for encouraging language development would involve intervention tailored to the individual needs of each child. However, given the practical barriers to implementing curricula tailored to individuals, play for learning should occur with groups of children who have similar backgrounds or abilities, at least at times.

Conclusions

What is the connection between play and language? Although Lillard et al. (2013) concluded that plays relationship to language learning could be causal or equifinal or epiphenomenal, we draw a stronger lesson from the current state of the evidence: Play is highly beneficial to childrens language skills and provides a supportive context for language learning. Specifically, play contexts contain a variety of elements that stimulate the kinds of conditions that grow language. These elements are likely not unique to play; rather, play is one of many contexts in which several of these elements converge (Weisberg, Hirsh-Pasek, & Golinkoff, 2013a).

This seems to be especially the case for the element of adult interaction. Guided play, which incorporates elements of adult scaffolding in service of a learning goal but which primarily follows a childs lead and builds on his or her interests, provides a particularly effective language-learning environment. Indeed, our definition of play emphasizes the need for it to be child-led. This means that situations like the directed play condition of the Head Start vocabulary-learning study (Dickinson et al., 2013) do not count as play. Here, an adult provided a script for the play session and asked the children to perform actions within that script --- a paradigm case of chocolate-covered broccoli. The main result from this study so far is that the guided play condition, which was more solidly child-directed, led to as much learning success as did this playful (but essentially non-play) situation. Thus, under some circumstances, adult guidance of childrens play can serve a learning goal as well as adult direction can.

This conclusion offers a new goal of early childhood education. Given that the same outcomes can potentially be achieved in situations where children themselves take the lead and genuinely enjoy learning, we suggest that such situations should replace at least some more adult-controlled play-like (but non-play) situations. This suggestion is in marked contrast to the current state of education, at least in the United States, which emphasizes drilling and testing over playing and exploring (see Miller & Almon, 2009). But our review shows that children who engage in play with attentive and responsive adults will improve their language skills. We thus urge that curricula should take advantage of this fact and incorporate places where children can feel free to follow their own interests in partnership with teachers.

Future work should investigate more fully plays role in the development of language skills and other key cognitive abilities. As we do so, we must keep in mind that the relative impact of play may change depending on the type of play and on the learner who is engaged in the play. As the Dickinson et al. (2013) results on maternal education level suggest, children become more able to take advantage of opportunities to learn through play as they become more advanced learners and social partners. We believe that these kinds of distinctions and individual differences will become even more important as we continue to investigate plays role in the development of language skills and other key cognitive abilities. In turn, this analysis suggests that we may need to refine our notions of what play is and what play can do; not all play is created equal.

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