Drawing a Dog: Cognitive Underpinnings Sabrina Panesi (sabrina.panesi@edu.unige.it) Dipartimento di Scienze della Formazione, corso A.Podestà 2 Genova, Italia Sergio Rivara (sergio-rivara@hotmail.it) Dipartimento di Scienze della Formazione, corso A.Podestà 2 Genova, Italia Sergio Morra (morra@nous.unige.it) Dipartimento di Scienze della Formazione, corso A.Podestà 2 Genova, Italia Abstract (Dennis, 1992; Morra, 2008a, 2008b) and inhibitory control (Riggs et al., 2013) in children’s drawing development. This study investigated preschoolers’ drawing flexibility, operationalized as their ability to draw a dog that is different Although human figure drawing was widely investigated, from the human figure. The role of working memory (M fewer studies investigated the development of drawing capacity) and executive function in drawing flexibility was animal figures (e.g., Lurçat, 1985). Silk and Thomas (1986) examined. The participants were 123 children, 36-73 months suggested that young children (three to six years old) may old. Regression analyses showed that both M capacity and acquire the graphic scheme for a dog by differentiation from executive function predicted development in dog drawing; the the human figure; Golomb (1992) provided converging dog drawing score correlated with M capacity and executive function even partialling out age, motor coordination, and evidence from young children’s drawings of other animals. drawing ability (measured with Goodenough’s Draw-a-man Consistent with Silk and Thomas’s view, both Reith (1988) test). These results suggest that both M capacity and and Morra (2005) found that school children’s drawings of a executive function play an important role in the early kangaroo are highly affected by their habitual scheme for development of drawing flexibility. the human figure. Children’s ability to modify their habitual drawing Keywords: drawing flexibility; working memory capacity; schemes is often referred to as “drawing flexibility”. This executive function; preschoolers term is related to the more general concept of flexibility as an ability not to follow in a rigid way an established routine or scheme. If drawing schemes for animals are initially Introduction differentiated from the human figure scheme, then explaining children’s creation of new schemes to draw animals can be regarded an important achievement in the How is the development of drawing ability related to the field of drawing flexibility. general development of the cognitive system during Explaining drawing flexibility is a controversial matter, childhood? Children’s human figure drawing has been however. An early account was proposed by Karmiloff- studied extensively (e.g., Goodenough, 1926; see also Cox Smith (1990), in the context of her Representational & Parkin, 1986; Freeman, 1980; Lange-Küttner, Kerzmann Redescription theory. Karmiloff-Smith (1990) suggested & Heckhausen, 2002). During an early stage of drawing that preschoolers are constrained by procedural rigidity, i.e., development, children typically use a single shape to they do not have access to their drawing procedures and represent both head and trunk and often include only a therefore they are not able to interrupt a habitual drawing single pair of limbs. By the time children finish preschool, procedure to make a novel drawing. Subsequent research they begin to differentiate the head from the trunk and to (Berti & Freeman, 1997; Spensley & Taylor, 1999; depict both arms and legs (Willcock, Imuta & Hayne, 2011). Spensley, 2001; Barlow, Jolley, White & Galbraith, 2003), In the pre-school years drawing skill develops markedly; however, reported evidence that falsified Karmiloff-Smith’s some studies investigated the cognitive mechanisms which account, because preschoolers seem to have access to their permit the development of representational drawing, drawing procedures. In particular, these studies showed that specifying the role of developing graphic and cognitive young children (a) can insert novel items midway through a skills (Freeman, 1980; Freeman & Adi-Japha, 2008; Jolley, drawing procedure, and (b) are able to produce a flexible 2008; Riggs, Jolley & Simpson, 2013). However, only a few drawing if the instructions and materials make it clear to studies focused on the relationships between the general them what type of modification is required. Karmiloff- development of the human cognitive system and drawing Smith (1999), in a reply to Spensley and Taylor (1999), development, suggesting a role of working memory capacity acknowledged that young children’s drawing procedures are not so rigid as she initially hypothesized. 395 A different account of drawing flexibility was proposed distinguished from broadly understood executive control by Morra (2005, 2008a), in the framework of neo-Piagetian (Wiebe, Scheffield, Nelson, Clark, Chevalier & Epsy, 2011; theory (e.g., Pascual-Leone & Johnson, 2005). This Miller, Giesbrecht, Muller, McInerney & Kerns, 2012; Usai, approach maintains that working memory growth has a Viterbori, Traverso & De Franchis, 2013).Therefore, we central role in cognitive development, and in particular, its used three working memory tests, widely used in neo- capacity can set an upper limit to drawing performance. In Piagetian research as measures of M capacity, and a battery this theoretical framework, attentional capacity (or M of four executive function tests (two of which tap inhibition, capacity) is considered as the core of working memory; the one updating, and one shifting), leaving to preliminary term “M capacity” indicates the maximum number of analyses the decision on whether inhibition as a basic, schemes that a person can simultaneously activate with general resource can be measured separately. Finally, we central attentional resources (Pascual-Leone, 1987). also used a motor coordination test as a control measure. Morra (2005) hypothesized that working memory is essential in drawing flexibility, because the child must keep Method in mind, in addition to a habitual scheme, its feature(s) that must be modified and the graphic devices that could Participants represent those modifications. Specifically, Morra (2005) The participants were 123 children, from 36 to 73 months examined the role of M capacity in drawing flexibility, with old (M = 53.1 months, SD = 9.6 months). There were 58 children in the age range from kindergarten to grade 3. Two experiments concerned drawing a human figure in girls and 65 boys, recruited in pre-schools in Genova and movement, and a third experiment required creating a novel Rapallo (Italy). Parents provided informed consent for scheme for drawing an unfamiliar animal (a kangaroo). The participation. results showed that, in this age range, working memory capacity was highly relevant both to modify the human Materials and Procedure figure scheme to represent specific movements, and to Drawing tasks differentiate a kangaroo from the human figure. Goodenough’s Draw-A-Man (Goodenough, 1926; Harris, A third relevant view was proposed by Barlow et al. 1963). The experimenter gave the child a white A4 sheet (2003), who suggested that young children are probably and a pencil, and invited the child to draw a man. rigid in encoding information that would lead to cognitive Instructions and scores were given according to the manual. overload if dealt with consciously, but a quantitative Dog Drawing Task. The experimenter gave the child a white increase in general information processing ability could A4 sheet and a pencil, and invited the child to draw a dog. enable the child to make a qualitative change in the way of The details of scoring are presented below. coping with that information. More particularly, they suggested that executive function development may aid the Motor coordination development of drawing flexibility (in line with the views TPV- subtest coordination eye-hand (Hammill, Pearson, & on executive function development proposed by Zelazo & Voress, 1994). This task assesses motor coordination. The Frye, 1997). In line with this view, Riggs et al. (2013) experimenter invited the child to trace with the pencil a showed a role of one executive function (i.e., inhibition) in standard set of routes. drawing development. This study has the general goal of investigating drawing Working memory tests flexibility in young children’s ability to draw a dog that is Mr. Cucumber test (Case, 1985). The outline of an different from the human figure. More particularly, the first extraterrestrial figure, to which colored stickers had been goal of this study is to create a scoring system for the dog attached, was displayed for 5 sec per item. There were three drawing task adequate for preschoolers. The second goal is items at each level from 1 to 8 stickers. The child must then to examine the role of M capacity and executive function in show, on an outline without colored stickers, the positions early drawing flexibility. of the stickers. The test was discontinued when a child Our second goal, however, poses a problem of choice of failed all three items at a level. One point was given for each models and measures for executive functions. Miyake, consecutive level on which a subject got at least two items Friedman, Emerson, Witzki, Howerter & Wager (2000) correct, and one-third of a point for each correct item above found that, in adults, inhibition, working memory updating, that level. and attention shifting are correlated but distinguishable Backward Word Span (Morra, 1994). The child was processes. Im-Bolter, Johnson & Pascual-Leone (2006) required to repeat lists of words backward. There were three proposed that M capacity and inhibition are general lists at each level from 2 to 7 words. The test was resources, whereas shifting and updating are executive discontinued when a child failed all three lists at one level. abilities that partly rely on M capacity and inhibition. This One point was given for each consecutive level on which a model, however, was tested on school children. The subject got at least two items correct (including level 1 structure of executive functions in preschoolers is widely which cannot exist, because it is not possible to reverse the debated, and it is still unclear at which age inhibition can be order of a list made of a single word, and therefore is 396 granted as correct by default), and one-third of a point for Puppets Updating Task. This is a novel task designed for each correct item above that level. this study; it assesses the constant monitoring and rapid Direction Following Task (DFT, Cunning, 2003; Pascual- addition or deletion of working memory contents. On each Leone & Johnson, 2005). This task requires children to item, the child was shown three, four or five puppets that follow oral directions of increasing complexity. We the experimenter placed sequentially in a cardboard house; modified it for preschoolers, using tokens of different then, the child must recall the last two puppets placed in the shapes (bike and boat), colors (white, yellow, green, blue house. There were 9 items, each of which was scored 1 and red) and size (large and small), to be placed in boxes of point if the child recalled correctly one puppet, and 2 points different color and size. We only presented items in the if the child recalled two puppets (possible range of scores, form “put X in Y” (i.e., the three simplest levels of 0-18). complexity of the test). There were five items at each level. The scoring rules for the Italian version of the test were Scoring of the Dog Drawing followed (see Morra, Camba, Calvini & Bracco, 2013). For the dog drawing task, a list of 13 features was prepared. This scoring was devised so that drawing flexibility could Executive function tasks be scored as independently as possible from general Day/Night Stroop (Gerstadt, Hong, & Diamond, 1994). This drawing development; i.e., only features in which the dog task assesses the ability to inhibit a prepotent verbal drawing was different from that of a person were response and to activate an alternative verbal response. considered. These features are listed in Table 1. One point Children were instructed that in this game they had to say was awarded for each feature (except feature 4 that was “night” to a white card with a yellow sun drawing, and scored 1 point in case 4a and half point in case 4b). Figure 1 “day” to a black card with a moon and stars on it. There presents an example of scoring. were 16 test trials; accuracy was scored (range 0-16). Bear/Dragon (Reed, Pien, & Rothbarth, 1984). This task assesses the ability to inhibit or activate a motor response following a rule, in a way similar to a go-no-go task. The experimenter introduced children to a “nice” bear puppet and a “naughty” dragon puppet, and explained that in this game they had to do what the bear told them to do (e.g., touch your nose) but not to do what the dragon said. There were 10 test trials, with bear and dragon commands in alternating order. The no-go trials were scored as follows: 0 Figure 1: Example of drawing, by a 57-month-old child. points for performing the movement commanded by the Numbers refer to the features listed in Table 1. dragon; 1 point for a partial movement or response; 2 points for performing a different movement from that commanded Table 1: Features considered in scoring and their proportion by the dragon; 3 points for no movement at all. The possible of occurrence scores for the no-go trials range from 0 to 15. Dimensional Change Card Sort (DCCS, Zelazo, 2006). This Feature Proportion is a complex response inhibition task. The DCCS creates a 1. Whole dog's figure length > height .43 prepotent response during the pre-switch phase that must 2. Head connected to body along the later be inhibited. The child was shown a deck of cards that horizontal axis .47 varied on two dimensions – shape (rabbit versus boat) and color (red versus blue). During the pre-switch phase, the 3. Pointed or elongated face .16 child must sort the card according to shape dimension. In 4a. Face details (nose at the end of the the post-switch phase, the child was asked to sort the card head) .05 according to color dimension. In the third sorting phase 4b. Face details (cat/bunny face; or (border phase), the experimenter explained that if there was mouth farther than eyes from the trunk) .06 a black border on a card, then the child must sort according 5. Pointed or hanging ears .28 to shape, and if there was not, according to colour. There 6. Whiskers .01 were 6 trials in the pre-switch phase, 6 in the post-switch 7. Tongue extending out of mouth .03 phase, and 12 in the border phase. The pre-switch and post- switch phases were scored 1 point if at least 5 responses out 8. Trunk length > height .45 of 6 are correct, and the border phase was scored 1 point if 9. Hair on body/legs .09 at least 9 out of 12 are correct.1 10. Four vertical legs .17 11. Paws (with animal shape) .05 1 Binary scores for each phase were used, instead of the number 12. Tail .40 of correct responses, because this strict scoring criterion is less 13. Dog objects (collar, leash, or muzzle) .02 vulnerable to the child’s random placing of cards in either box. 397 Results scores in the latter three tests. Note that M capacity is conceived as a general, attentional resource at the core of All dog drawings were scored by a second rater. Table 2 working memory capacity, and therefore the finding of a presents the reliability (proportion of inter-rater agreement factor that loads both verbal and visuo-spatial tasks is fully and Cohen’s kappa) of each single feature scored in the dog consistent with the theoretical assumptions. drawing task. The proportion of inter-rater agreement on each single feature ranged .89 to 1 (mdn = .97); Cohen’s Table 3: Descriptive Statistics Kappa ranged .49 to 1 (mdn = .87), and all of them were Std. significant with p<.001. Cronbach’s alpha was .77, and the N Mean Dev. Min Max correlation between the total scores given by the two raters Drawing Tasks was r(121) = .96, p<.001. Thus, all reliability indexes were good. Goodenough’s Draw-A-Man 123 9.87 6.29 0 28 Table 2: Inter-rater reliability Dog Drawing Task 123 2.64 2.46 0 7 Motor coordination proportion of Cohen's p of Tpv - subtest eye-hand inter-rater Kappa Cohen's coordination 122 113.5 32.98 28 172 agreement Kappa 1. Whole dog's figure length > M capacity tests height .89 .79 <.001 Mr. Cucumber Test 120 1.59 .79 0 4 2. Head connected to body along horizontal axis .94 .87 <.001 Backward Word Span 120 1.66 .74 1 3.66 3. Pointed or elongated face .97 .88 <.001 Direction Following Task 122 1.54 1.06 0 3.5 4. Face details .58 <.001 Executive Function Tasks 4a. Face details (nose at the end of the head) .98 Night/Day Stroop 122 10.48 4.48 0 16 4b. Face details (cat/bunny face; Bear/Dragon no go 120 9.01 6.47 0 15 or mouth farther than eyes from the trunk) .95 DCCS 120 2 .43 1 3 5. Pointed or hanging ears .93 .82 <.001 Puppets Updating 120 11.63 3.08 2 18 6. Whiskers 1 1 <.001 7. Tongue extending out of mouth .99 .89 <.001 The dog drawing scores increased with age, r(121) = .77, p<.001. The correlation between working memory capacity 8. Trunk length>height .97 .93 <.001 and the dog drawing score was highly significant, r(117) 9. Hair on body/legs .96 .72 <.001 =.73, p<.001, also with age partialled out, r(116) = .33, 10. Four vertical legs .98 .91 <.001 p<.001. The correlation between executive function and the 11. Paws .98 .79 <.001 dog drawing score was also highly significant, r(114) = .65, p<.001, also with age partialled out, r(113) = .29, p = .002. 12. Tail .95 .90 <.001 The dog drawing also correlated with the Goodenough 13. Dog's objects (collar, leash, or muzzle) .98 .49 <.001 Draw-a-man test r(121) = .69, p<.001, also with age partialled out, r(120) = .26, p = .002, and with motor coordination r(120) = .53, p<.001, but this correlation didn't Table 3 shows the descriptive statistics.2 A factor analysis resist partialling out age. of the working memory and executive function tests (with A stepwise regression analysis of the dog drawing scores, principal axis extraction and varimax rotation) found two with M capacity, executive function, motor coordination, factors. The Backward Word Span, DFT, and Mr.Cucumber and the draw-a-man scores as predictors, yielded significant Test loaded higher on the first factor (.93, .49, and .47, results for M capacity (Beta = .40, p<.001), Draw-a-man respectively), while the Bear/Dragon, the Day/Night Stroop, (Beta = .31, p<.001), and executive function (Beta = .18, and the Puppets Updating loaded higher on the second p<.03), thus accounting for 62.8% variance overall. factor (.65, .63, and .63, respectively). The DCCS did not Another regression analysis was run, in which age was load highly on any factor, probably because of lack of entered first, accounting for 60.0% of the dog drawing variance in this sample. Therefore, we defined an M scores; M capacity, executive function, motor coordination, Capacity variable as the mean of the first three tests, and an and the draw-a-man scores were entered subsequently, with executive function variable as a weighted mean of the z a stepwise method. This analysis showed that both M capacity and executive function contributed significantly to 2 the dog drawing scores, accounting together for another A few children did not perform all tasks; N=123 in the analyses that only consider the drawing task, whereas in 5.8% variance above and beyond age. In the final equation, correlation and regression analyses we only considered the the significant predictors were age (Beta = .46, p<.001), M children who contributed all relevant data points. 398 capacity (Beta = .26, p<.01), and executive function (Beta = figure, and monitor the ongoing process to optimize changes .17, p<.04). in the habitual scheme (Barlow et al., 2003). 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