Evidence for a relation between executive function and pretense representation in preschool children

Highlights

• A developmental relation between executive function (EF) and pretense is investigated in the preschool period.

• A large battery of EF measures fit both a 1-factor and a 2-factor (Conflict and Delay) model in a confirmatory factor analysis.

• Individual differences in pretense representation and EF were significantly related, over and above several controls.

• Understanding the pretend–reality distinction was related to Conflict EF, whereas performing pretend actions was related to Delay EF.

• A bidirectional between EF and pretense is proposed, with implications for pretend play interventions designed to foster EF development.

Abstract

Several theoretical formulations suggest a relation between children's pretense and executive function (EF) skills. However, there is little empirical evidence for a correlation between these constructs in early development. Preschool children (N = 104; M age = 4–0) were given batteries of EF and pretense representation measures, as well as verbal, memory, and appearance-reality control tasks. Confirmatory factor analysis revealed two separable but overlapping aspects of EF (Conflict and Delay). EF was significantly related to pretense after accounting for all controls. Understanding the pretend–reality distinction was strongly related to Conflict EF, whereas performing pretend actions was more strongly related to Delay EF. These results, although correlational, are consistent with the claim that EF skills are implicated in pretense, such as inhibiting reality and flexibly manipulating dual representations, and offer a potential mechanism by which pretend play interventions may enhance childhood EF.

Introduction

One of the most surprising and charming features of early childhood is the frequency with which children – who have much to learn about the real world – engage in pretend play, where reality is distorted on purpose. Scholars have wondered whether there might be important cognitive benefits of pretense beyond suggested social-emotional benefits (Bretherton, 1989, Singer and Singer, 1990). One such benefit concerns executive functioning (EF), the cognitive processes that aid in self-control of thought and action (Carlson, Zelazo, & Faja, 2013). Important developments take place in children's EF during the early preschool years, at the very time when fantasy and pretense are most prevalent. The development of EF skills, mediated by prefrontal and other cortical changes, may play a crucial role in children's ability to entertain multiple, conflicting mental representations, which are displayed prominently in pretense. Moreover, pretense clearly involves an inhibitory component: Children must inhibit the tendency to refer to an actual, veridical state of affairs so that non-reality representations can arise and be maintained. Conversely, experience with pretend play may contribute to gains in EF by providing a way to reframe real-world events and problems and think more flexibly. We therefore aimed to examine the strength and nature of a relation between preschool children's EF and pretense representation skills.

Pretense follows a consistent developmental timeline (Carlson and Zelazo, 2008, Fein, 1981, Garvey, 1991). In the second year of life, toddlers attribute living characteristics to a nonliving object (e.g., a stuffed animal) and transform objects, such as pretending a banana is a phone. By age 2, children appear to understand the pretend overtures of others, such as wrapping a towel around a teddy bear when an adult “spills” imaginary tea over it (Harris and Kavanaugh, 1993, Lillard and Witherington, 2004). Gradually during the preschool years, pretending becomes less dependent on props and more abstract. For example, children will knock on an imaginary door of an imaginary house and serve imaginary food to imaginary people. The preschool period is considered the apex of make-believe play, when an estimated 40% of children in Western cultures have imaginary companions (Gleason et al., 2000, Singer and Singer, 1990, Taylor, 1999). As children enter middle childhood, organized games become more common than overt pretense, although children (and many adults) continue to have active imaginations (Singer and Singer, 1990, Taylor, 1999).

Concurrent with the development of pretense skills is the rapid acquisition of EF, which entails goal-directed behavior, including inhibition, working memory, and set-shifting (Garon et al., 2008, Hughes, 1998, Miyake et al., 2000, Zelazo et al., 1997). EF is increasingly recognized as a critical component of children's cognitive and social functioning (for review see Carlson et al., 2013). One category of EF tasks concerns the ability to control impulses, often in the face of tempting rewards (Kochanska et al., 1996, Reed et al., 1984). For example, Kochanska et al. (1996) gave children a Gift Delay task, in which an examiner instructs them not to peek while she noisily wraps a present for them. Children's waiting ability on such “delay” tasks improves across the preschool period. The second category, “conflict” EF, includes measures calling for children to respond a certain way in the face of a highly salient, conflicting response option, but there is no extrinsic reward and the task rules are relatively decontextualized from daily behavior (Diamond and Taylor, 1996, Frye et al., 1995, Gerstadt et al., 1994, Reed et al., 1984). For example, following Luria's (1966) pioneering work, Gerstadt et al. (1994) presented 3- to 7-year-olds with cards depicting either the sun or moon and instructed them to say “night” in response to sun cards and “day” in response to moon cards. Children's performance improved gradually from age 3 to 7 years. Significant improvements were found from age 3 to 5 years on an adaptation of this task in which children needed to point to a white card when the examiner said “grass” and to a green card when the examiner said “snow” (Carlson, 2005, Carlson and Moses, 2001).

Both delay and conflict EF are conceptualized as drawing on the same top-down control processes, and they are correlated in preschoolers (Carlson & Wang, 2007), but dissociations have been reported in which relatively “hot” or affective EF is delayed relative to “cool” EF, perhaps because emotional arousal can undermine control processes (Zelazo & Carlson, 2012). Furthermore, although there is a literature showing one latent factor for EF in the preschool period using largely cool EF measures (Wiebe et al., 2008, Wiebe et al., 2011), several studies of preschoolers by Carlson and colleagues have found overlapping but distinct factors for conflict EF measures, which are relatively cool and require considerable working memory e.g., (Grass/Snow), and delay EF measures, which are relatively hot because they involve a delay of gratification for a tempting reward or response (e.g., Gift Delay; Carlson and Moses, 2001, Carlson et al., 2002). The dissociation between conflict and delay EF appears as early as toddlerhood (Bernier et al., 2010, Morasch and Bell, 2011).

A long-standing question about pretend play is how young children are capable of generating and understanding pretense representations despite such underdeveloped cognitive and brain systems? Different answers have been proposed, but leading developmental theories of pretense appear to have a common focus, which is the ability to hold two (or more) different representations of the same thing in mind without becoming confused regarding reality. Scholars including Olson (1991), Friedman and Leslie (2005), Harris, 1994, Harris, 2000, and Lillard, 1993, Lillard, 2001 have offered explanations for how children maintain the boundary between pretense and reality. Each of these theories has in common the claim that pretense takes place at a level of representation that is somehow separated or distant from reality, and that meta-awareness of such representational acts may not come until relatively late in the preschool years (for review, see Carlson & White, 2013). Yet we are left with the question of how this occurs – what are the psychological or neural mechanisms involved? In our view, EF provides a plausible domain-general mechanism to help account for how children manage dual representations in pretense.

As noted earlier, pretend play becomes more decontextualized, that is, distant from reality. Pretend themes result from children's increasing ability to imaginatively manipulate various event scripts in a broad representational system (Carlson & Zelazo, 2008). Older children are capable of imagining highly fantastical scenarios, such as a world in which miniature aliens speak and perform all activities backward. This decontextualization is akin to Werner and Kaplan's (1963) theory of psychological distancing (see also Dewey, 1985, Hegel, 1807). Sigel (1970) adopted this term to mean “behaviors or events that separate the child cognitively from the immediate behavioral environment” (p. 111), which lead to representational competence – “the individual's awareness and understanding that an instance can be represented in various forms and still retain its essential meaning” (Sigel, 1993, p. 142).

Similarly, Vygotsky (1967) suggested that pretense is instrumental to internalization, that is, the development of internal systems of representation that assist children in freeing themselves from external stimulus control and permit thinking about objects and events not immediately present. These systems include language (private speech) and what might be referred to today as EF. Vygotsky also noted a paradox in children's make-believe play: Rather than being spontaneous and “free,” it requires the suppression of impulses so that social rules for behavior can be followed (Nicolopoulou, 1991). Golomb and Kuersten's (1996) research has shown that even 3-year-olds are well aware of the boundary between pretense and reality, and they balk when reality intrudes on make-believe play, such as when a researcher really bites into a Playdoh cookie.

Flexible executive control over mental representations and prepotent responses may be the central feature that binds these theories regarding the cognitive underpinnings of pretense. We suggest that young children become increasingly adept at managing conflicting mental representations in pretense (and eventually with metacognitive awareness) in concert with EF development.

Empirical evidence of a connection between EF and pretense is sparse. Only a handful of correlational studies have uncovered relations between EF and symbolic play skills. In a short-term longitudinal study, Elias and Berk (2002) observed 53 3- and 4-year-olds during free play and clean-up periods in a preschool setting. They found that the complexity and duration of play with a partner in the beginning of the school year predicted increases in compliance on the clean-up task observed 8 months later, independent of age and vocabulary level. In another study, Albertson & Shore (2009) presented 32 preschoolers with an object (e.g., a block) and explained its pretend identity (e.g., a phone). Children's ability to later recall both the real and pretend identities of an object significantly correlated with scores on a set of three conflict EF tasks. Finally, after controlling for mental age, Kelly and Hammond (2011) found a relation between structured pretend play and a version of the Day/Night inhibitory control task among preschoolers. Although these studies reveal a link between pretense and self-regulation, they were limited by several factors, such as small sample sizes for correlational analyses and few behavioral measures of EF and control variables. Moreover, each of the EF tasks used in these studies focused on relatively “cool” regulatory abilities, leaving the relation between pretense and hot or delay EF unaddressed.

A broader spectrum of measures in a large sample is needed to apprehend the full nature of the relation. It is especially important to examine the links between pretense and both the cool and hot facets of EF. Although not yet explored, it is possible that pretense representation relates to hot/delay EF just as strongly as cool/conflict EF. Such correlational evidence can serve as a basis for deciding whether pretense might serve as a useful tool for helping to improve EF in young children.

Experimental evidence suggests that pretense representation serves to “cool down” and thus improve performance on a challenging “hot” task. Mischel and Baker (1975) first demonstrated this when preschoolers children were able to delay gratification for longer intervals when instructed to pretend that the tempting stimulus (e.g., a marshmallow) was something less tempting (e.g., a white fluffy cloud). Similarly, Carlson, Davis, and Leach (2005) introduced a symbolic context to facilitate children's performance on Less is More, an EF task in which children need to point to a smaller number of treats in order to receive a larger number of treats. Degrees of symbolic distancing had incremental effects on 3-year-olds’ ability to override the prepotent response of pointing to the larger array. When symbols were used to represent the treats, the more abstract or decontextualized the symbol, the greater their control over their responses (see also Apperly & Carroll, 2009). This work suggested a relation between symbolic representation (as in pretense activities) and self-control over thought, action, and emotion. Further empirical evidence is nevertheless needed on the nature and strength of relation between EF and pretense in a large sample, independent of confounding variables.

We hypothesized that individual differences in EF would be significantly positively related to children's representational skills in the domain of pretense, over and above differences that might be attributable to age, verbal ability, memory capacity or understanding of the appearance-reality distinction. We further predicted that the correlations would hold not only for cool EF, but also for relatively hot, affective measures of executive control.