Beyond irrelevant actions: Understanding the role of intentionality in children’s imitation of relevant actions

Journal of Experimental Child Psychology 119 (2014) 54–72

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Beyond irrelevant actions: Understanding the role of intentionality in children’s imitation of relevant actions Amy K. Gardiner ⁄ Department of Psychology, Skidmore College, Saratoga Springs, NY 12866, USA

a r t i c l e

i n f o

Article history: Received 13 March 2013 Revised 18 October 2013 Available online 3 December 2013 Keywords: Imitation Intentionality Irrelevant actions Preschoolers Evolution Causal understanding

a b s t r a c t The current research examines how 3- to 5-year-old children use intentionality to understand the causal structure of objects in an observational learning context. Two studies are presented in which the intentionality of relevant actions was manipulated during toy retrieval demonstrations and contrasted with whether these actions remained relevant or were rendered irrelevant for the child’s turn. Of interest were whether children would imitate the first action when it was demonstrated intentionally but rendered irrelevant and how they would approach the first action when it was demonstrated accidentally and remained relevant. Findings revealed that children did not align themselves with the demonstrator’s intentions in Study 1, when apparatuses were transparent, but did follow the demonstrator’s intentions in Study 2, when apparatuses were opaque. This suggests that when causality of relevant actions is unambiguous, children use their own causal reasoning abilities, but ambiguous causal structure prompts children to defer to a demonstrator. It is suggested that opaque relevant actions may represent a real life parallel to irrelevant actions, the imitation of which is motivated by inherent ambiguity. Ó 2013 Elsevier Inc. All rights reserved.

Introduction Social learning is a critical part of development and remains fundamental throughout the lifespan. Research on children’s social learning abilities has revealed an early proficiency for learning by observ-

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ing the behavior of others. Many studies have investigated preschoolers’ observational learning strategies within the domain of object use, focusing on the degree to which children copy observed actions. The study of preschoolers’ imitation of irrelevant actions, which are causally unnecessary for completing a task, has become a focus for many researchers. Irrelevant actions were originally included in demonstrations of toy retrieval tasks to explore children’s social learning strategies (Horner & Whiten, 2005). Of interest was whether children would emulate, broadly defined as copying an observed goal using means other than those observed, or whether they would imitate, broadly defined as copying an observed goal using the observed means. Emulation would require children to recognize that irrelevant actions were unnecessary and omit these actions from their performance, whereas imitation would require them to copy all observed actions, including the irrelevant ones. It was found that children did not emulate but instead chose to imitate, including the irrelevant actions, in their toy retrieval attempts (Horner & Whiten, 2005). Since this behavior was demonstrated, children’s imitation of irrelevant actions has captured the interest of researchers around the world, whose varied approaches are gradually piecing together an understanding of this phenomenon (Flynn, 2008; Kenward, 2012; Lyons, Damrosch, Lin, Macris, & Keil, 2011; McGuigan, Makinson, & Whiten, 2010; McGuigan, Whiten, Flynn, & Horner, 2007; Nielsen, Moore, & Mohamedally, 2012; Simpson & Riggs, 2011). The behavior of copying irrelevant actions is usually referred to as overimitation, but this term seemingly implies that children imitate something above and beyond what they observed. Thus, the term overimitation undermines the fact that when children imitate irrelevant actions they are actually imitating very precisely, copying everything that they observe, and can be reasonably characterized as a misnomer. Given this, the term indiscriminate imitation, implying that children imitate all observed actions regardless of causal relevance, is preferred and used in this article. In addition to providing greater accuracy in describing imitation of irrelevant actions, using the term indiscriminate imitation allows for a category in which children actually do perform observed actions in excess of what was demonstrated, a behavior that can be termed perseverative imitation (Gardiner, Greif, & Bjorklund, 2011). Indiscriminate imitation has been demonstrated under a range of different conditions with children from industrialized nations (Horner & Whiten, 2005; Lyons et al., 2011; McGuigan et al., 2007) as well as traditional African Bushman communities (Nielsen & Tomaselli, 2010). Interestingly, the precision with which children imitate appears to increase during very early childhood under conditions where adults provide realistic demonstrations in which they appear knowledgeable, draw children’s attention to the task at hand, and successfully achieve the task goal. In these circumstances, indiscriminate imitation of object use emerges reliably by 3 years of age and continues into adulthood (McGuigan et al., 2010). Studies with younger children and infants demonstrate that earlier imitation of object use under these conditions is selective, based on factors such as the physical rationality of the demonstrator’s actions (Gergely, Bekkering, & Kiraly, 2002; Schwier, van Maanen, Carpenter, & Tomasello, 2006) and the level of the demonstrator’s social engagement (Brugger, Lariviere, Mumme, & Bushnell, 2007; Nielsen, 2006). This suggests that during very early childhood infants and children may be more likely to rely on their own independent evaluation of object causal structure, but by the preschool age they become more likely to rely on a demonstrator to gain this knowledge. Studying and explaining why children imitate irrelevant actions is interesting in its own right, but it is important to keep in mind that including intentionally performed irrelevant actions in demonstrations of object use occurs primarily in experimental settings. In real life, there should be no good reason for a knowledgeable individual to purposefully include irrelevant actions in a demonstration of object use. Thus, in their everyday learning of object use, children should almost always be observing and imitating relevant actions. Therefore, the current research does not focus on what indiscriminate imitation can tell us about why children imitate irrelevant actions. Rather, one aim of this work was to comprehend the phenomenon of indiscriminate imitation in a way that may have practical application to understanding how children learn about everyday objects as they observe demonstrations that do not include superfluous actions. With similar reasoning, Gardiner and colleagues (2011) sought to place indiscriminate imitation in a functional framework, proposing that it might reflect an evolved learning mechanism. In that study, children were provided with demonstrations of object use in which irrelevant actions were performed with verbal markers to indicate that the actions were intentional (‘‘There!’’) or accidental (‘‘Whoops! I

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didn’t mean to do that!’’). The authors found that 3-, 4-, and 5-year-olds imitated irrelevant actions when they were performed intentionally but not when they were performed accidentally. This suggests that preschool children use the intentions of a demonstrator to guide their understanding of which actions should be performed to make objects function (Gardiner et al., 2011). Given that demonstrations of object use that include intentional unnecessary actions should be rare, both in our modern lives and throughout human history, Gardiner and colleagues suggested that presuming all intentional actions are causally necessary is a reasonable assumption that would almost always lead to a correct understanding of how to use objects. Thus, indiscriminate imitation may represent an evolved capacity for the accurate cultural transmission of adaptive knowledge of how to use objects and tools. This presumption would have been more efficient than the alternative—assuming that a demonstrator’s intentional actions did not contribute to object function, leaving one to determine how to use an object independently. Such a trial-and-error learning process could be detrimental if it turned out to be futile and resulted in the loss of critical, adaptive tool-use knowledge. Thus, imitating all intentional actions would have been selected during human evolution as a means of accurate and efficient transmission of such important information (Gardiner et al., 2011). The work of Gardiner and colleagues (2011) establishes intentionality as a guiding factor in children’s understanding of which actions are causally necessary for object function when children learn by observing others; intentional actions are consistent with causal relevance, whereas accidental actions are consistent with causal irrelevance. However, their study varied the intentionality of only actions that were actually causally irrelevant. The primary aim of the current work was to go beyond irrelevant actions to investigate whether children also use intentionality to guide their understanding of causal necessity in the more realistic context of relevant actions. In Study 1, children were presented with demonstrations in which three relevant actions were performed to retrieve toys from within a series of apparatuses constructed of clear plastic materials. The first action was differentially marked as intentional (‘‘There!’’) or accidental (‘‘Whoops! I didn’t mean to do that!’’). For the child’s turn, the first action either remained causally relevant for toy retrieval or was rendered irrelevant so that only the second and third actions needed to be performed. This created two conditions in which the intentionality of the demonstration was inconsistent with the causal relevance of the actions for the child’s turn and two conditions in which intentionality and relevance were consistent. Table 1 provides a summary of the study design. Of primary interest were whether children would perform the first action when it was causally irrelevant, given that it had been demonstrated intentionally, and how children would approach the first action when it was causally relevant but had been demonstrated accidentally. This inconsistency between intentionality and causality is similar to conditions created by DiYanni and Kelemen (2008), who investigated whether children would use intentionality in a tool-use context where a demonstrator’s intentions clashed with tool functionality. In this series of studies, an experimenter accidentally chose, and subsequently rejected, a functional tool and then intentionally chose a nonfunctional tool, which she attempted to use to crush a cookie. In contrast to the findings of Gardiner and colleagues (2011), the majority of 2- to 4-year-old children in most conditions did not follow the demonstrator’s intentions, instead selecting the functional tool even though it had been chosen accidentally and rejected. The condition in the current study where a relevant action is performed accidentally and remains relevant for the child’s turn is similar to the pairing by DiYanni and Kelemen (2008) of an accidental choice with a functional tool, whereas the condition where a relevant action is performed intentionally but rendered irrelevant for the child’s turn is similar to DiYanni and Kelemen’s pairing of an intentional choice with a nonfunctional tool. The findings of DiYanni and Kelemen suggest that children discriminated which tool was functional and privileged this functionality over the intentionality of the demonstrator. If children in the current study privilege causal relevance over intention, they should choose not to imitate the first action when it is rendered irrelevant even if it was intentionally demonstrated, and they should not hesitate to imitate the first action when it remains relevant even if it was demonstrated accidentally. In contrast, if children use intentionality to guide their causal understanding of relevant actions, they should imitate an intentionally demonstrated action even if it is rendered irrelevant. If an action is demonstrated accidentally but remains relevant, children will need to perform it to succeed on the task, so it is expected that they will perform the action in this condition. However, if

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Table 1 Research design. Demonstration: Intentionality of first action

Child’s turn: Relevancy of first action

Condition

Consistency of intentionality and causality

Intentional

Relevant

Intentional Relevancy Retained Intentional Relevancy Removed

Consistent

Accidental Relevancy Retained Accidental Relevancy Removed

Inconsistent

Control Relevancy Retained Control Relevancy Removed

n/a

Irrelevant Accidental

Relevant Irrelevant

No demonstration

Relevant Irrelevant

Inconsistent

Consistent

n/a

their understanding of object function is based on the intentionality of the demonstrator, they should believe that the accidentally demonstrated action is irrelevant, which would need to be revised when they were presented with the task and this action is relevant. If a revision of causal understanding is necessary, children may show increased latency to perform the first action in this condition. In two conditions where the intentionality of the demonstration was consistent with the relevancy of the first action for the child’s turn, it was expected that children would follow the intentions of the demonstrator, imitating the first action when it is demonstrated intentionally and remained relevant and ignoring the first action when it is demonstrated accidentally and rendered irrelevant. Study 1 Method Participants Participants were 58 children (29 girls and 29 boys, age range = 37–71 months): 18 3-year-olds (M = 41.11 months, SD = 2.56), 21 4-year-olds (M = 53.14 months, SD = 3.07), and 19 5-year-olds (M = 62.53 months, SD = 2.74). Most children were White and from middle and upper class backgrounds. Materials Six different apparatuses were used, each containing a series of transparent plastic compartments and three moving parts. A small stuffed animal could be maneuvered through and retrieved from each apparatus by manipulating the moving parts. The toy could be placed in either the first compartment or the second compartment to begin the sequence of toy movement. Placing the toy in the second compartment rendered the first moving part irrelevant to retrieval. If the toy began in the second compartment, the first moving part could still be fully manipulated. Apparatuses for Study 1 are pictured in Appendix A. Procedure All apparatuses were kept behind a barrier with an assistant, who passed each apparatus through a door in the barrier as it was needed. A within-participants design was used, with all children participating in four demonstration conditions and two control conditions. For the demonstrations, the toy began in the first compartment. In the demonstration conditions, the assistant passed an apparatus to the demonstrator, who placed it in front of herself and said, ‘‘Look at this.’’ She then pointed to the toy to highlight its position and said, ‘‘See the [animal]? I’m going to get the [animal] out.’’ She performed the first action, followed by the second action, followed by the third action, and retrieved the toy.

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During each demonstration, the intentionality of the actions was manipulated using verbal markers. Whereas the second action and third action were always marked as intentional (‘‘There!’’), the first action was differentially marked as intentional or accidental. In two of the demonstrations the first action was marked as intentional, indicated by the word ‘‘There!’’, and in the other two demonstrations the first action was marked as accidental, indicated by the phrase, ‘‘Whoops! I didn’t mean to do that!’’ For the child’s turn, the demonstrator passed the apparatus back to the assistant, who reset the apparatus behind the barrier. In resetting each apparatus, the first action either remained relevant, by placing the toy in the first compartment, or was rendered irrelevant, by placing the toy in the second compartment. This varied with whether the first action was demonstrated intentionally or accidentally, creating four conditions (see Table 1). There was consistency between intentionality and causality in the Intentional Relevancy Retained condition, where the first action was performed intentionally and remained relevant for the child’s turn, and in the Accidental Relevancy Removed condition, where the first action was performed accidentally and rendered irrelevant for the child’s turn. There was inconsistency between intentionality and causality in the Intentional Relevancy Removed condition, where the first action was performed intentionally and rendered irrelevant for the child’s turn, and in the Accidental Relevancy Retained condition, where the first action was performed accidentally and remained relevant for the child’s turn. After the apparatus was reset out of sight, the experimenter pointed to the toy to highlight its position (‘‘See the [animal]?’’) and then placed the apparatus in front of the child, who was encouraged to retrieve the toy (‘‘Now it’s your turn. Can you get the [animal] out?’’). In the two control conditions, children were presented with an apparatus and encouraged to retrieve the toy on their own without prior demonstration. In the Control Relevancy Retained condition, the toy was placed in the first compartment and all three actions were required for retrieval. In the Control Relevancy Removed condition, the toy was placed in the second compartment and the second and third actions were required for retrieval. Each toy retrieval attempt ended when the child was successful or after 3 min had elapsed. The structure of three apparatuses (lever shuttle, stair step tube, and elevator) allowed for the toy to become stuck if the moving parts were manipulated out of order. If this happened, the experimenter waited 10 s to give the child a chance to realize that the toy was irretrievable before saying, ‘‘Uh oh! Looks like the animal is stuck! Let’s go on to the next one.’’ This was an infrequent occurrence. Each condition occurred with each apparatus approximately equally often across participants. The order was counterbalanced so that the three different kinds of conditions (intentional, accidental, and control) alternated, with no two conditions of the same kind ever occurring in direct sequence. In addition, the relevancy of the first action for the child’s turn was counterbalanced so that it alternated between retained and removed across the six conditions. All sessions were videotaped. Results Task performance The majority of children retrieved the toy in all conditions. A comparison of success rates revealed that there were significant differences between the Relevancy Retained conditions, Cochran Q, v2(58) = 9.65, p < .01. The success rate in the Control Relevancy Retained condition (69.0%) was significantly lower than success rates in the Intentional (87.9%) and Accidental (86.2%) Relevancy Retained conditions (McNemar tests, all ps < .05). The rate of success in the Control Relevancy Removed condition (79.3%) was lower, but not significantly different, than success rates in the Intentional (86.2%) and Accidental (87.9%) Relevancy Removed conditions. To further investigate the effect of viewing a demonstration on children’s performance, the efficiency with which children completed the tasks was compared across conditions. Efficiency was measured by summing the number of times each child manipulated the apparatus in each condition. A manipulation was defined as an instance of contact made with an apparatus, including touches and movements of moving parts and exploratory touches on nonmoving parts. One analysis compared the three conditions in which relevancy of the first part was retained for the child’s turn, and another compared the three conditions in which relevancy was removed. Results show that the demonstrations facilitated children’s performance. For the Relevancy

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Retained conditions, children performed significantly more manipulations in the Control condition (M = 13.88, SD = 17.05) than in the Intentional (M = 5.93, SD = 4.93) and Accidental (M = 6.84, SD = 7.20) conditions, F(2, 114) = 9.47, p < .001, g2 = .17 (Bonferroni post hoc tests, all ps < .01). For the Relevancy Removed conditions, children performed significantly more manipulations in the Control condition (M = 11.40, SD = 11.55) than in the Accidental condition (M = 6.84, SD = 9.54), F(2, 114) = 4.20, p < .05, g2 = .07 (Bonferroni post hoc test, p < .05). Children performed more manipulations in the Control condition than in the Intentional condition (M = 8.33, SD = 8.76), but the difference was not significant. This pattern of findings suggests that even though most children successfully achieved the toy retrieval goal in all conditions, they were engaged in independent exploratory learning to a significantly higher degree when they were not provided with a demonstration. When a demonstration was available, children learned from their observations, which allowed greater efficiency in task completion. Scoring of actions Children received a first action score, a second action score, and a third action score for each condition that reflected the degree to which they manipulated the respective moving parts of each apparatus. The 0-to-4 scale from Gardiner and colleagues (2011) was used. This scale is related to the precision with which children’s manipulations replicated the experimenter’s actions. A score of 0 reflected making no contact with a part, a score of 1 reflected touching but not moving a part, a score of 2 reflected moving a part partially (less than demonstrated), a score of 3 reflected moving a part fully (exactly as demonstrated), and a score of 4 reflected ‘‘overmoving’’ a part (in excess of the demonstration). There was one exception to this coding procedure. Whereas the experimenter did not reset any of the moving parts after she manipulated them during the demonstration, during their attempts at toy retrieval many of the children moved parts back to their original positions after using them to maneuver toys through the compartments of the apparatuses. For instance, if a trap door needed to be pulled out to drop a toy into a subsequent compartment, children would often push the trap door back in after the toy was released before moving on to the next part. In most cases, this did not appear to be an attempt to elicit a further effect from the moving part; children just seemed to have a simple desire to reset the parts. Many children even reset the third part after retrieving the toy. Thus, resetting a moving part was not coded as overmoving the part but was coded as fully moving a part. If children further manipulated a part after resetting it, this was scored as overmoving the part. Scores were assessed from video footage by two independent trained coders. The first coder then scored 30% of the second coder’s videos to determine interrater reliability. The intraclass correlation coefficient was .92. Analysis of action scores To understand how the intentionality of the demonstrator and the relevancy of the actions affected children’s performance, each action score were assessed in a separate mixed analysis of variance (ANOVA) with age as a between-participants factor and with intentionality (i.e., of the first action during the demonstration: intentional, accidental, or no demonstration control) and relevancy (i.e., of the first action for the child’s turn: retained or removed) as within-participants factors. A preliminary analysis revealed no effects of gender, and this factor was not included in subsequent analyses. Bonferroni tests were used for all post hoc comparisons. Table 2 shows means and standard deviations for the first, second, and third action scores across all participants in each of the six conditions. Analysis of the first action score revealed a main effect of relevancy, F(1, 55) = 60.58, p < .001, g2 = .52. Regardless of whether there was no demonstration in the Control conditions or demonstration of the first action was intentional or accidental, children had higher first action scores when relevancy was retained for their turn (M = 3.16, SD = 0.37) than when relevancy was removed (M = 2.06, SD = 1.12) (see Fig. 1). There was no effect of age in analysis of the first action. Analysis of the second and third action scores revealed no significant effects. It was expected that the first action score would reflect fully manipulating the first part in all Relevancy Retained conditions because this part needed to be manipulated to retrieve the toy. Therefore, this score is not informative as to whether children were using the demonstrator’s intentions in the Accidental Relevancy Retained condition. In this condition, if children had an understanding that the first action was irrelevant because it was performed accidentally, they might show increased

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Table 2 Means and standard deviations for action scores: Study 1. Condition

First action

Second action

Third action

SD

M

SD

M

SD

Relevancy Retained Intentional Accidental Control

3.05 3.10 3.33

0.69 0.52 0.60

3.07 2.98 3.02

0.45 0.69 0.85

2.95 3.10 2.72

0.76 0.52 1.28

Relevancy Removed Intentional Accidental Control

2.05 1.88 2.24

1.77 1.68 1.73

3.00 2.93 2.74

0.53 0.59 0.83

3.10 2.95 2.93

0.64 0.69 0.99

f

s

M

Fig. 1. First action scores for all conditions (Study 1), grouped by relevancy (retained or removed). Bars represent standard errors.

latency to perform the first action as they revise their causal understanding of the action. Because only 15 children performed the first action in all conditions, planned comparisons were conducted to compare the latency to perform the first action between conditions. Latency scores of zero, for children who did not perform the first action, were excluded from each comparison. No significant differences were found (all ts < 2.05, all ps > .05). Discussion Study 1 examined the role of intentionality in children’s imitation of relevant actions using objects constructed of transparent materials. In contrast to findings from Gardiner and colleagues (2011), in which intentionality guided children’s imitation of causally irrelevant actions, causality predominated over intentionality in children’s performance of relevant actions. The reversal of the relationship between intentionality and relevancy suggests that the intentionality framework used to explain children’s imitation of irrelevant actions in Gardiner and colleagues’ study cannot be extended to describe how children interpret the necessity of relevant actions. The disparity in findings suggests that children process relevant and irrelevant actions differently during observational learning of object use. An explanation for this may be provided by the ideas of Csibra and Gergely (2006, 2011; see also Gergely & Csibra, 2005). In their pedagogical framework,

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these authors describe potential evolved cognitive mechanisms underlying the social learning of tool use. They suggest that because complex human tools have multiple possible functions, observable tool-use behavior is cognitively opaque. In other words, a learner knows neither the background knowledge of a demonstrator nor the ultimate goal (i.e., desired tool function) of his or her actions. Even if a goal is described or inferred, the action sequence to achieve it remains unknown. Given cognitive opacity, tool-use learning mechanisms would have evolved a provision to process observable tooluse behavior while still providing an accurate and efficient means of cultural transmission. Csibra and Gergely (2006) described this provision as an assumption of relevance; learners assume that demonstrators provide a physically rational approach to achieving a goal and, therefore, that all actions performed are relevant. This assumption is apparent in children’s indiscriminate imitation; irrelevant actions, known by the demonstrator to be causally unnecessary, are cognitively opaque to the learner, who applies the assumption of relevance and imitates the irrelevant actions. The findings of Gardiner and colleagues (2011) support a qualifying intentionality component for irrelevant actions; children assume that all intentional irrelevant actions are relevant. In addition, a corresponding assumption of irrelevance is applied to accidental irrelevant actions. It does not appear that children in Study 1 used the demonstrator’s intentionality to apply assumptions of relevance or irrelevance. The predominance of actual causal relevancy in Study 1 is consistent with the pattern of results found by DiYanni and Kelemen (2008), in which the majority of children discounted the intentionality of a demonstrator in favor of functional properties when making tooluse choices. One explanation for children privileging physical causality in these studies relates to a component of Csibra and Gergely’s pedagogical framework; learners may bring to the observational learning context preexisting causal knowledge, which they can apply to their understanding of how a tool or an object works, thereby constraining their perceptions of a demonstrator’s actions (Csibra & Gergely, 2006). This idea has also been asserted by other researchers (Bonawitz et al., 2011; Buchsbaum, Gopnik, Griffiths, & Shafto, 2011; Goodman, Baker, & Tenenbaum, 2009). In Study 1, the demonstrated actions had physical effects that were readily observable (e.g., when a support was removed from beneath the toy, the toy fell). These obvious physical effects appear to have made these actions cognitively transparent; how they causally contribute to making the object work was evident and unambiguous. Thus, understanding of the causal structure of the objects is based on children’s strong prior understanding of physical causation and, therefore, resistant to other elements of the demonstration such as the intentionality of the demonstrator. Indeed, DiYanni and Kelemen (2008) provided children with a familiarization period in which they interacted with the materials used in the subsequent demonstrations. During this exploration, children may have discovered through independent experiential learning certain functional properties of the tools that allowed them to easily recognize that the nonfunctional tool would not work to complete the demonstrated task, overwhelming most effects of intentionality. If children were learning from the demonstrations but interpreting what they observed using their own causal reasoning, the social learning strategy that children employed in Study 1 might not be best described as imitation. Rather, their performance may reflect learning through goal emulation, in which a learner adopts a demonstrator’s intended goal but determines an action sequence independently (see Call & Carpenter, 2002, for delineation of social learning strategies based on different sources of information from which learners can draw). The proposal that actions are cognitively transparent when they have observable physical effects and, thus, are causally unambiguous suggests that irrelevant actions are cognitively opaque because of the causal ambiguity created by a lack of readily observable physical effects. In other words, that irrelevant actions do not physically contribute to making an unfamiliar object function might not be apparent to a naive learner. With an expectation of a rational demonstrator who will provide a correct display of object use (Buchsbaum et al., 2011; Goodman et al., 2009; Shafto & Goodman, 2008), the learner defers to the demonstrator rather than relying on his or her own causal reasoning and applies an assumption of relevance. This leads to the incorporation of irrelevant actions into the learner’s understanding of object causal structure. Given the rarity of irrelevant actions in real-life object-use demonstrations, such a stance would typically result in learning all of the actions necessary to making an object function and no unnecessary actions.

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If lack of observable physical effects makes irrelevant actions cognitively opaque, this suggests that if the physical effects of relevant actions are unobservable, they should be rendered cognitively opaque and subject to the same processing biases as irrelevant actions are in an observational learning context. With this logic in mind, the physical effects of the first moving part of each apparatus were shrouded for Study 2. This created literal opacity, which for relevant actions should translate to cognitive opacity and lead children to incorporate the intentionality of the demonstrator into their understanding of which actions are necessary. The causal ambiguity of opaque relevant actions may make them the closest real-life equivalent to irrelevant actions. Thus, Study 2 may provide valuable insight into how our knowledge of irrelevant action imitation can be applied to children’s everyday learning of objects. Study 2 Method Participants Participants were 58 children (26 girls and 32 boys, age range = 36–71 months), none of whom took part in the first study: 18 3-year-olds (M = 41.61 months, SD = 3.79), 20 4-year-olds (M = 53.90 months, SD = 3.16), and 20 5-year-olds (M = 65.35 months, SD = 3.44). Most children were White and from middle and upper class backgrounds. Materials The six apparatuses from Study 1 were used, with the effect of the first action made opaque by shrouding the first and second compartments of each apparatus with black shelf liner paper that adhered to the plastic. Apparatuses for Study 2 are pictured in Appendix B. Slight modifications were made to four of the apparatuses (lever shuttle, chute, elevator, and stair step tube) to make particular moving parts more manageable for children to manipulate. These modifications did not affect the range of motion of the moving parts or the effects they had on maneuvering or retrieving the toy. Procedure The procedure from Study 1 was used with two modifications related to how the toys were presented to the children. To maintain opacity in Study 2, the demonstrator began each condition by presenting a toy to the child and saying, ‘‘See the [animal]? I’m going to give the [animal] to [assistant] and she’s going to put it inside the game for us.’’ The demonstrator then passed the toy behind the barrier to the assistant, who placed the toy within an apparatus and then passed it to the demonstrator. The demonstrator placed it in front of herself and said, ‘‘Now the [animal] is inside of here. I’m going to get the [animal] out,’’ and proceeded as in Study 1. For the child’s turn in the demonstration conditions, on receiving a reset apparatus from the assistant, the demonstrator placed it in front of the child as she said, ‘‘Now the animal is back inside of here. It’s your turn. Can you get the [animal] out?’’, and the procedure continued as in Study 1. The Control conditions began in the same manner as the other conditions, with the demonstrator presenting a toy to the child and passing it to the assistant for placement in an apparatus. On receiving the apparatus, the demonstrator placed it in front of the child and provided the same instruction for the child’s turn as in the other conditions. All sessions were videotaped. Results Task performance The majority of children retrieved the toy in all conditions except the Control Relevancy Retained condition. Comparison of success rates revealed that there were significant differences between the Relevancy Retained conditions, Cochran Q, v2(58) = 11.72, p < .01, and between the Relevancy Removed conditions, Cochran Q, v2(58) = 12.08, p < .01. The success rate in the Control Relevancy Retained condition (46.6%) was significantly lower than that in the Intentional Relevancy Retained

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condition (77.6%) (McNemar test, p < .01) and lower than, but not significantly different from, that in the Accidental Relevancy Retained condition (56.9%). The rate of success in the Control Relevancy Removed condition (68.4%) was significantly lower than success rates in the Intentional (89.7%) and Accidental (87.9%) Relevancy Removed conditions (McNemar tests, all ps 6 .01). As in Study 1, to further investigate the effect of viewing a demonstration on children’s performance, the efficiency with which children completed the tasks was compared across conditions. The approach to measurement and analysis from Study 1 was used. For the Relevancy Retained conditions, children performed significantly more manipulations in the Control condition (M = 15.72, SD = 15.31) than in the Intentional condition (M = 7.19, SD = 6.99), F(2, 114) = 8.72, p < .001, g2 = .13 (Bonferroni post hoc test, p = .001). Children performed more manipulations in the Control condition than in the Accidental condition (M = 10.86, SD = 8.87), but the difference was not significant. For the Relevancy Removed conditions, children performed significantly more manipulations in the Control condition (M = 12.45, SD = 10.35) than in the Intentional (M = 5.57, SD = 5.49) and Accidental (M = 4.98, SD = 5.22) conditions, F(2, 114) = 18.94, p < .001, g2 = .25 (Bonferroni post hoc tests, all ps < .001). As in Study 1, this pattern of findings suggests that even though most children successfully achieved the toy retrieval goal in most conditions, they were engaged in independent exploratory learning to a significantly higher degree when they were not provided with a demonstration. When a demonstration was available, children learned from their observations, which allowed greater efficiency in task completion. Scoring of actions Using the scoring procedure from Study 1, for each condition children received a first action score, a second action score, and a third action score that reflected the degree to which they manipulated the respective moving parts of each apparatus. Scores were assessed from video footage by a trained coder. A second trained coder then scored 30% of the first coder’s videos to determine interrater reliability. The intraclass correlation coefficient was .99. Analysis of action scores To understand how the intentionality of the demonstrator and the relevancy of the actions affected children’s performance, each action score was assessed in a separate mixed ANOVA with age as a between-participants factor and with intentionality (i.e., of the first action during the demonstration: intentional, accidental, or no demonstration control) and relevancy (i.e., of the first action for the child’s turn: retained or removed) as within-participants factors. A preliminary analysis revealed no effects of gender, and this factor was not included in subsequent analyses. Bonferroni tests were used for all post hoc comparisons. Table 3 shows means and standard deviations for the first, second, and third action scores in each of the six conditions. Analysis of first action scores (see Fig. 2) revealed main effects for intentionality, F(2, 110) = 24.52, p < .001, g2 = .31, and relevancy, F(1, 55) = 27.11, p < .001, g2 = .33, as well as an interaction between intentionality and relevancy, F(2, 110) = 6.45, p < .01, g2 = .11. Children had lower scores when demonstration of the first action was accidental (M = 2.08, SD = 1.08) than when demonstration was intentional (M = 3.05, SD = 0.46) or there was no demonstration in the Control conditions (M = 3.04, SD = 1.04). Children had lower scores when relevancy of the first action was removed for their turn (M = 2.45, SD = 0.68) than when relevancy was retained (M = 2.99, SD = 0.71). To analyze the interaction between intentionality and relevancy, t tests compared first action scores between the Relevancy Retained and Relevancy Removed conditions for each level of intentionality. When demonstration of the first action was intentional or there was no demonstration in the Control conditions, Relevancy Retained and Relevancy Removed scores were not significantly different (both ps > .10). When demonstration of the first action was accidental, Relevancy Retained scores (M = 2.64, SD = 1.35) were higher than Relevancy Removed scores (M = 1.50, SD = 1.51), t(57) = 4.51, p < .001, d = 0.80. Because children needed to perform the first action to retrieve the toy in the Accidental Relevancy Retained condition, this difference was expected. Analysis of second action scores revealed main effects for age, F(2, 55) = 5.94, p < .01, g2 = .18, intentionality, F(2, 110) = 8.91, p < .001, g2 = .14, and relevancy, F(1, 55) = 4.00, p = .05, g2 = .07, as well as an interaction between intentionality and relevancy, F(2, 110) = 6.10, p < .01, g2 = .10. The 3-year-olds (M = 2.86, SD = 0.35) had significantly lower second action scores than the 4-year-olds (M = 3.13,

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Table 3 Means and standard deviations for action scores: Study 2. Condition

First action

Second action

Third action

SD

M

SD

M

SD

Relevancy Retained Intentional Accidental Control

3.10 2.64 3.21

0.52 1.35 1.15

3.07 3.52 2.79

0.45 0.50 1.23

3.07 3.03 2.33

0.49 1.11 1.47

Relevancy Removed Intentional Accidental Control

2.98 1.52 2.84

0.71 1.51 1.51

3.00 3.00 2.97

0.46 0.32 0.94

3.03 2.97 2.67

0.49 0.56 1.21

f

s

M

Fig. 2. First action scores for all conditions (Study 2), grouped by relevancy (retained or removed). Bars represent standard errors.

SD = 0.28) and 5-year-olds (M = 3.16, SD = 0.24). In a pattern opposite that of first action scores, children had higher second action scores when demonstration of the first action was accidental (M = 3.26, SD = 0.27) than when demonstration was intentional (M = 3.03, SD = 0.32) or there was no demonstration in the Control conditions (M = 2.88, SD = 0.80). Children had lower second action scores when relevancy of the first action was removed for their turn (M = 2.98, SD = 0.35) than when relevancy was retained (M = 3.12, SD = 0.46). To analyze the interaction between intentionality and relevancy, t tests compared second action scores between the Relevancy Retained and Relevancy Removed conditions for each level of intentionality. The pattern of findings for second action scores mirrored that for first action scores. When demonstration of the first action was intentional or there was no demonstration in the Control conditions, Relevancy Retained and Relevancy Removed second action scores were not significantly different (both ps > .30). When demonstration of the first action was accidental, Relevancy Retained scores (M = 3.52, SD = 0.50) were higher than Relevancy Removed scores (M = 3.00, SD = 0.32), t(57) = 6.01, p < .001, d = 0.02. Analysis of third action scores revealed a main effect of intentionality, F(2, 110) = 16.49, p < .001, g2 = .23. Children had lower third action scores when there was no demonstration in the Control conditions (M = 2.50, SD = 0.91) than when there was a demonstration regardless of whether demonstration of the first action was intentional (M = 3.05, SD = 0.32) or accidental (M = 3.00, SD = 0.62). Returning to results for first action scores, there was a consistent pattern across the two Intentional conditions: Regardless of whether the first action was retained or removed for their turn, when it was

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demonstrated intentionally children performed it. This suggests that children were taking the demonstrator’s intentionality into account in understanding which actions should be performed to retrieve the toys from within the apparatuses, and intentional actions were considered causally meaningful. Scores in the Accidental conditions were lower than those in the Intentional conditions when collapsed across relevancy, but action scores are less informative for how children might be taking intentionality into account in the Accidental conditions. This is particularly the case in the Accidental Relevancy Retained condition because children needed to perform the first action to retrieve the toy. Analysis of order of manipulation To better understand the relationship between intentionality and children’s understanding of causality, particularly in the Accidental conditions, the next set of analyses focused on the order in which children manipulated the moving parts, with particular emphasis on which moving part was manipulated initially. If children believe that the first action is necessary, they should imitate the demonstrator and begin their toy retrieval attempts by initially manipulating the first moving part. In contrast, if children do not believe that the first action is necessary, they should not imitate the first action and should begin their toy retrieval attempts by manipulating the second moving part. If their understanding of the causal necessity of the first action is based on the demonstrator’s intentionality, with intentional actions understood as causally necessary and accidental actions understood as causally unnecessary, children should initially manipulate the first part in the Intentional conditions and the second part in the Accidental conditions. In the following analyses, the part children initially manipulated is considered the first moving part that children made contact with in their interaction with an apparatus regardless of the degree to which they manipulated this part. Mean action scores for the initially manipulated part fell primarily between 2.00 and 3.00, suggesting that children typically manipulated their first-chosen part to a substantial degree. Cochran Q tests compared the rates of initially manipulating the first, second, and third parts within each Intentional condition and each Accidental condition, and follow-up McNemar and exact binomial tests revealed specific differences between the rates of initial manipulation of the three moving parts (see Fig. 3). Consistent with an understanding of causality based on demonstrator intentionality, in both Intentional conditions children were more likely to manipulate the first part than the second or third part (both ps < .001). In addition, in the Accidental Relevancy Retained condition, children were more likely to manipulate the second part than the first or third part (both ps < .001). However, in the Accidental Relevancy Removed condition, children were equally likely to manipulate the first and second parts (p = .09) and more likely to initially manipulate the second or first part than the third part (both ps < .05). In the Accidental Relevancy Removed condition, correct manipulation of the second action would move the toy into the transparent third compartment, and children could then manipulate the third action to retrieve the toy. Therefore, it is surprising that children were not more likely to initially manipulate the second part than the first part in this condition, especially given that they appeared to follow the demonstrator’s intentions and attempt to omit the first action in the Accidental Relevancy Retained condition. However, an examination of the order in which children experienced the two Accidental conditions reveals why some children began their toy retrieval attempts by manipulating the first part when relevancy was removed. This analysis focused on children who initially manipulated either the first part or the second part in the Accidental conditions. In the Accidental Relevancy Retained condition, children who initially manipulated the first part and children who initially manipulated the second part were equally likely to do so regardless of whether they experienced this condition before or after the Accidental Relevancy Removed condition (Fisher’s exact tests, both ps > .50). In the Accidental Relevancy Removed condition, however, children who initially manipulated the first part were more likely to have experienced this condition before the Accidental Relevancy Retained condition (p = .001), whereas children who initially manipulated the second part were more likely to have experienced this condition after the Accidental Relevancy Retained condition (p = .02) (Fisher’s exact tests) (see Fig. 4). This order effect suggests that children were learning from their experience in the Accidental Relevancy Removed condition and applying the knowledge gained to the Accidental Relevancy Retained condition. There are several possibilities for what children were learning addressed in the Discussion below.

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Fig. 3. Percentages of children whose initial manipulation was of the first, second, and third moving parts for the Intentional and Accidental conditions (Study 2).

Fig. 4. Percentages of children whose initial manipulation was of the first and second moving parts for the Accidental conditions, as a function of condition order (Study 2). Black bars represent children who experienced the Accidental Relevancy Retained condition prior to the Accidental Relevancy Removed condition; gray bars represent the opposite order.

Discussion Study 2 investigated whether children would incorporate the intentionality of a demonstrator into their understanding of the causality of relevant actions that had unobservable physical effects due to opaque materials. It was hypothesized that opacity would make these actions causally ambiguous in the same way that irrelevant actions are, thereby subjecting them to the intentionality-based processing observed in Gardiner and colleagues’ (2011) study. In contrast to Study 1 and consistent with the findings of Gardiner and colleagues, children imitated the first action when it was performed intentionally and largely omitted or attempted to omit the first action when it was performed accidentally regardless of whether it remained relevant or was rendered irrelevant for their turn. Findings from Study 2 fit within the framework advanced by Gardiner and colleagues that children incorporate

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the intentionality of the demonstrator into their understanding of which observed actions are causally meaningful. In the Intentional conditions, results are straightforwardly supportive of intentionality-based causal reasoning. In the Accidental conditions, findings required deeper exploration but also revealed performance consistent with the interpretation that children derived their understanding of object function from the demonstrator’s intentions. In the Accidental Relevancy Retained condition, most children performed the first action during their interaction with the object. However, they were most likely to begin manipulating the object by performing the second action, attempting to bypass the accidentally demonstrated first action. This suggests that children’s initial impression of the object’s causal structure was based on the intentionality of the demonstrator—the accidental action was perceived as causally unnecessary—and they revised this understanding once they realized that the second action would not result in the expected effect of maneuvering the toy into the third compartment. Children’s performance in the Accidental Relevancy Removed condition was affected by the order in which they experienced the two accidental conditions. A detailed assessment of this effect reveals a spectacular relationship between an understanding of causality based on intentionality and independent learning. If children experienced the Accidental Relevancy Removed condition after the Accidental Relevancy Retained condition, they were likely to begin with the first part even though it had been performed accidentally. It appears that children applied knowledge gained in the Accidental Relevancy Retained condition to their performance in the Accidental Relevancy Removed condition. The experience that most children had in the Accidental Relevancy Retained condition was following the demonstrator’s intentions and attempting to omit the first action, realizing a revision of causal structure was necessary, and then manipulating the first part. This suggests that during their interaction with the object in the Accidental Relevancy Retained condition, children became aware of the inconsistency between the demonstrator’s intentions and the causal structure of the apparatus. There are at least two possibilities for what knowledge children gained from this realization that they then applied in the Accidental Relevancy Removed condition. One is that children were learning that three distinct actions were necessary for making the objects function, working from the top downward or from right to left. Another is that children were learning that the demonstrator’s accidental actions should not be regarded as mistakes and were actually necessary despite the accidental performance. The likelihood of the first possibility can be investigated by looking at children’s performance in the Control conditions. If children were generalizing knowledge about the physical structure of the apparatuses, it would be expected that they would be able to determine how to retrieve the toys with relative ease in Control conditions that followed the Accidental Relevancy Retained condition but would have greater difficulty in Control conditions that preceded the Accidental Relevancy Retained condition. This would be reflected in greater degrees of exact manipulation of the first part in Control conditions that followed the Accidental Relevancy Retained condition, because children would be expected to manipulate this part fully but not beyond what was necessary, and greater degrees of manipulation in excess of the demonstration in Control conditions that preceded the Accidental Relevancy Retained condition, because children would be expected to engage in considerable exploration of the apparatus. To analyze this, the rate of exact manipulation of the first part (first action score = 3) was compared with the rate of excess manipulation (first action score = 4). The data show that children were more likely to engage in exact manipulation in Control conditions that occurred before the Accidental Relevancy Retained condition (McNemar test, p < .001), and there was no effect of where a Control condition fell in relation to the Accidental Relevancy Retained condition on children’s likelihood to engage in excess manipulation (McNemar test, p = .44). This suggests that children were approaching each apparatus as an individual problem-solving task rather than generalizing the structure of the apparatuses across conditions. Thus, it is likely that children were taking the knowledge that the demonstrator’s accidental actions were not unnecessary, gained during the Accidental Relevancy Retained condition, and applying it to their interaction with the apparatus in the Accidental Relevancy Removed condition. However, children who experienced the Accidental Relevancy Removed condition prior to the Accidental Relevancy Retained condition did not have the experience of discovering inconsistency between the demonstrator’s accidental performance and the necessity of the first action in the Accidental Relevancy Retained condition. Without this prior experience, these children aligned themselves with the demonstrator’s

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intentions in the Accidental Relevancy Removed condition, omitting the first action, beginning with the second action, continuing to the third action, and retrieving the toy. Turning briefly to the Control conditions, children demonstrated a high degree of manipulation of the first action, with a sizable proportion of children perseverating beyond what was necessary (53.4% in the Control Relevancy Retained condition and 50.0% in the Control Relevancy Removed condition). Given the causal ambiguity created by the opaque materials, this is an expected result and it suggests that many children were engaging in exploration of the apparatus. This interpretation is consistent with findings that children engage in more exploration when they are presented with confounded causal evidence than when causal relationships are disambiguated (Schulz & Bonawitz, 2007; Schulz, Gopnik, & Glymour, 2007). Thus, children appear to have a motivation to disambiguate causal structure (Schulz & Bonawitz, 2007). Given their high degree of exploration, children in the current study certainly appeared motivated to understand how to make the objects function in the Control conditions. This exploration frequently led to success, with nearly half of children (46.6%) retrieving the toy in the Control Relevancy Retained condition and the majority (67.2%) retrieving the toy in the Control Relevancy Removed condition. That children can discover causal structure during their own exploratory experience with objects is consistent with previous research (Schulz et al., 2007). Relative to the exploration shown in the Control conditions, the close imitation of the demonstrator’s intentional behavior shown in the four demonstration conditions highlights how adept children are at gathering information about objects through observation, with particular attendance to a demonstrator’s intentions. Furthermore, this shows that when children are given the chance to observe a demonstration of an object with causally ambiguous physical structure, they will take advantage of the opportunity to garner knowledge about object function from someone else rather than attempting to determine causality through independent trial-and-error learning.

General discussion The current work provides an enriched picture of how children use intentional understanding to learn about novel objects in an observational context. When relevant actions had clearly visible physical effects, children’s imitation indicates that they chose to forgo the demonstrator’s intentionality as reflective of object function, instead relying on their own causal reasoning to determine which actions were necessary. In contrast, when the effects of relevant actions were unobservable, children’s imitation indicates an understanding of causality that relied on the demonstrator’s intentions. The predominance of relevancy over intentionality in Study 1 indicates that children enter the observational learning with an understanding of causal relationships that can facilitate an accurate interpretation of the functions of relevant components of an object. This is consistent with research on children’s causal reasoning abilities showing that children are able to derive patterns of cause and effect from novel demonstrations (Buchsbaum et al., 2011; Schulz, Hooppell, & Jenkins, 2008). However, the predominance of intentionality over relevancy in Study 2, as well as the multitude of studies in which children have been shown to indiscriminately imitate irrelevant actions performed on novel objects (e.g., Lyons et al., 2011; McGuigan et al., 2007, 2010; Nielsen & Tomaselli, 2010), provides clear evidence that children use their own causal reasoning abilities selectively in observational learning contexts and will often choose instead to follow the example provided by a demonstrator. The current studies provide insight as to what prompts children to rely on a demonstrator to learn about the function of novel objects rather than relying on themselves. Taken together, findings suggest a contingency between the degree of cognitive opacity within the observational learning context and whether children will apply their own understanding of causal relationships or defer to a demonstrator. This explanation is derived partially from the ideas of Csibra and Gergely (2006, 2011; see also Gergely & Csibra, 2005), outlined earlier, regarding cognitive opacity. Recall that a tool-use scenario can be described as cognitively opaque when the goal and/or intended action sequence of a demonstrator is unknown to a learner. With an expectation that a demonstrator provides a physically rational display of object use, a learner applies an assumption of relevance and presumes that all demonstrated actions are necessary.

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The current work suggests that in the context of learning about novel objects through observation, some actions fall into the category of cognitive opacity, whereas others fall into a corresponding category of cognitive transparency in which there is little causal ambiguity and object function is obvious to a learner. Based on the current studies, one criterion for classification of relevant actions is whether they have observable physical effects; relevant actions that have observable physical effects can be classified as cognitively transparent, whereas relevant actions that have unobservable physical effects can be classified as cognitively opaque. When actions are cognitively transparent, as with the relevant actions in Study 1, children appear to discount the demonstrator’s intentionality as a source of information about object function. Rather, given the lack of causal ambiguity, children evaluate causal structure independently. In contrast, the difference in children’s performance between the intentional and accidental conditions in Study 2 suggests that the opacity of the objects created a degree of causal ambiguity that compelled children to rely on the demonstrator to learn about the causal structure of the objects. In this context, children’s understanding of object function was guided by the demonstrator’s intentions, with an assumption of relevance applied to intentionally performed actions and an assumption of irrelevance applied to accidentally performed actions. In sum, there is an inverse relationship between cognitive opacity and children’s reliance on their own causal reasoning abilities in observational learning contexts; cognitively transparent actions facilitate children’s independent causal reasoning, whereas cognitively opaque actions lead to reliance on a demonstrator. As suggested earlier, irrelevant actions can be classified as cognitively opaque, and this cognitive opacity appears to be due to a lack of observable physical effects. The categorization of irrelevant actions as cognitively opaque, based on lack of observable physical effects, is supported by several findings. First, children’s performance in Study 2, which involved relevant actions with unobservable physical effects, was similar to children’s performance in the study by Gardiner and colleagues (2011), where irrelevant moving parts had no effect on toys placed inside transparent plastic containers. In both studies, children aligned themselves with the demonstrator’s intentions, imitating intentionally performed actions and omitting or attempting to omit accidentally performed actions. This suggests that children process opaque relevant and transparent irrelevant actions similarly, with the actions having in common a lack of observable physical effects. Second, several studies have used objects constructed of transparent and opaque materials to compare children’s imitation of transparent and opaque irrelevant actions (Horner & Whiten, 2005; McGuigan et al., 2007, 2010), finding that children imitated irrelevant actions regardless of whether they could observe if the actions had an effect. This suggests that it is not whether children have the opportunity to observe the lack of physical effects but rather the lack of physical effects in and of itself that renders irrelevant actions cognitively opaque. If this characterization of irrelevant actions is correct, children may imitate these actions because causality is difficult to assess and they are relying on the demonstrator to gain an understanding of causal structure. Given the opportunity to learn about the function of a novel object by observing a demonstration, it is advantageous for children to defer to the demonstrator to understand causality because social learning is more likely to facilitate efficient and accurate acquisition of object knowledge than is independent causal learning. To illustrate this point, consider a real-life instance of observational learning of object use in which a knowledgeable individual provides a demonstration of how an object properly functions. In this realistic scenario, intentionally performed irrelevant actions would, in all likelihood, be nonexistent. Thus, adopting a social learning strategy and relying on the demonstrator would lead to an accurate understanding of causality. In contrast, presuming that the demonstrator could not provide useful information in this causally ambiguous context and that independent determination of causality was required could ultimately prove to be a futile learning strategy. As suggested by Gardiner and colleagues (2011), imitating all intentionally performed actions would have been selected for during human evolution as a means of efficiently acquiring important tool-use knowledge rather than an assumption that one should determine causality independently. The latter strategy could be maladaptive if essential tool-use knowledge is never discovered and disappears from the culture. At the same time, however, choosing to rely on oneself rather than a demonstrator can be beneficial in a situation where the demonstration appears to be unreliable. An ability to discern such a situation was shown by children who experienced the Accidental Relevancy Removed condition after the Acci-

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dental Relevancy Retained condition in Study 2. In the Accidental Relevancy Retained condition, children attempted to omit the first action but then learned that this accidentally demonstrated action was actually necessary. They subsequently performed the first action in the Accidental Relevancy Removed condition, suggesting that they had recognized that the demonstrator’s accidental cues were not a reliable source of information about causality. Thus, given the apparent unreliability of the demonstrator in the Accidental Relevancy Retained condition, children chose not to rely on her in the Accidental Relevancy Removed condition. Instead, in the Accidental Relevancy Removed condition, they relied on the knowledge that they had gained from their own interaction with the apparatus in the previous accidental condition and assumed that the first action was necessary. One aim of this work was to describe how knowledge of indiscriminate imitation might be applied to our understanding of how children learn about novel objects in everyday contexts where irrelevant actions are rare. Findings of the current research and previous studies (e.g., Gardiner et al., 2011; Horner & Whiten, 2005) may elucidate this relationship. Specifically, experimentally artificial irrelevant actions may represent a parallel to real-life relevant opaque actions; both present causal ambiguity to an object learner, and children imitate both with a high degree of precision. Thus, studies in which children indiscriminately imitate irrelevant actions may reveal a general proclivity for relying on a demonstrator to learn about object function when causality is ambiguous. However, the current studies and that of Gardiner and colleagues (2011) reveal that such reliance is affected by characteristics of the demonstrator’s behavior such as intentionality. In sum, the current research goes beyond imitation of irrelevant actions to reveal how children use a demonstrator’s intentionality to learn about relevant actions and suggests that causal ambiguity in general may be an important factor that children use to evaluate whether the intentionality of a demonstrator’s actions is reflective of causality and can be used as a guide for imitation. The potential parallel between irrelevant actions and opaque relevant actions suggests a possible expansion of the scope of impact that studies investigating indiscriminate imitation may have on our understanding of the ways in which children learn to use objects by observing others. Acknowledgements The second study was supported in part by the National Science Foundation under Grant Number 0820080 and the Skidmore – Union Network (SUN) Committee, and Skidmore College. Appendix A. Apparatuses with three-step manipulation sequences (transparent): Study 1

Lever Shuttle First action: top vertical lever Second action: push stick Third action: side door

Double-Decker Box First action: button Second action: top trap door Third action: bottom trap door

Chute First action: top sliding vertical trap door Second action: flip down trap door Third action: hinged door

Percolator First action: flip down trap door Second action: sliding horizontal trap door Third action: latched trap door

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Stair Step Tube First action: rotating horizontal trap door Second action: push stick Third action: latched trap door

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Elevator First action: hooked seesaw lever Second action: elevator Third action: top sliding push paddle

Appendix B. Apparatuses with three-step manipulation sequences (opaque): Study 2

Lever Shuttle First action: top vertical lever Second action: push stick Third action: pull down trap door

Double-Decker Box First action: button Second action: top sliding trap door Third action: bottom sliding trap door

Chute First action: top sliding vertical trap door Second action: flip down trap door Third action: hinged door

Percolator First action: flip down trap door Second action: sliding horizontal trap door Third action: latched trap door

Stair Step Tube First action: top rotating horizontal trap door Second action: push stick Third action: latched trap door

Elevator First action: magnetically connected seesaw lever Second action: elevator Third action: top sliding push paddle

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