Brief ReportThe spatial–numerical congruity effect in preschoolers
Highlights
► Three-to four-year-old preschoolers were tested for directional spatial-numerical congruity. ► Children have shown left-to-right SNARC-like bias in numerosity comparison task. ► The bias was found in children before acquisition of reading and counting principles.
Introduction
The problem of the relation between number and space representations reveals several interesting issues in numerical cognition (for reviews, see Hubbard et al., 2005, Wood et al., 2008). Such an association is shown, for instance, by the SNARC (spatial–numerical association of response codes) effect (Dehaene, Bossini, & Giraux, 1993); responses to relatively small numbers are performed faster on the left side (e.g., with the left hand or button), whereas responses to large numbers are performed faster on the right side, even if the task does not require direct magnitude processing (e.g., in parity judgment). It has been argued that this kind of effect reflects mapping numbers onto the horizontal dimension from left to right (mental number line model).
The most prominent explanation of the origins of the left-to-right number representation accentuates the special role of enculturation (for a recent review, see Goebel, Shaki, & Fischer, 2011). Many authors assume that spatial–numerical associations are predominantly shaped by reading direction specific to a given culture (Dehaene et al., 1993, Shaki et al., 2009, Zebian, 2005) and also by the direction of numerical orders (Lindemann, Abolafia, Pratt, & Bekkering, 2008) or measuring tools (Bächtold, Baumüller, & Brugger, 1998). In effect, it is widely believed that this kind of number–space mapping does not emerge before the beginning of primary school, when most of these directional tools are introduced for the first time (van Galen & Reitsma, 2008).
We claim, nevertheless, that these data do not necessarily imply that the left-to-right spatial organization of number magnitudes evolves entirely on the basis of the above-studied experiences, although their impact is indisputable. Recently, left-to-right bias was found in the sequential search for a given numerically determined (e.g., fourth, sixth) position in an ordered row of objects in preliterate preschoolers (Opfer, Thompson, & Furlong, 2010) and even in birds (Rugani, Kelly, Szelest, Regolin, & Vallortigara, 2010). Thus, it seems that preliterate experiences and biological constitution can also be considered as explanations for the directional preferences in numerical representation. It should then be investigated whether cultural experiences such as reading, writing, and mathematical tools are indeed crucial factors for creating spatial–numerical associations.
The majority of research about spatial–numerical associations has used digit or number word stimuli, which are acquired together with other cultural tools that could determine the directional biases. However, it is often claimed that symbolic number representations may originate from a nonsymbolic approximate system for numerosity processing that develops spontaneously and prior to education in infants, nonliterate tribal cultures, and several species of animals (Feigenson, Dehaene, & Spelke, 2004). Importantly, nonverbal numerical estimation may interact with the processing of spatial length in infants and preliterate children (de Hevia and Spelke, 2009, de Hevia and Spelke, 2010, Lourenco and Longo, 2010), suggesting initial predisposition of the human mind to connect numbers with space in general. However, it is unclear whether such a connection is also formed as a left-to-right spatially organized representation similar to that in older children familiar with reading and writing. So far, nonverbal spatial–numerical effects have been found in adults who were estimating outcomes in a nonsymbolic addition/subtraction task (Knops, Viarouge, & Dehaene, 2009) or approximating non-numerical magnitudes such as duration (Vallesi, Binns, & Shallice, 2008). These studies confirmed the validity of using nonsymbolic stimuli in spatial–numerical tasks, but no research with younger participants has been yet reported.
In the current study, we have designed a task based on nonsymbolic numerosity processing and recruited young preschoolers who had not yet been formally schooled and had not yet acquired counting principles (CP knowledge), which is regarded as a crucial step in the development of a symbolic number system (Le Corre & Carey, 2007). It allowed us to study the spatial–numerical associations not only before literacy acquisition but also before the influence of mathematical language.
A typical SNARC task with bimanual reactions to a central target (Dehaene et al., 1993) requires arbitrary mapping between the response and the response key, which is too demanding for young preschoolers. Some other SNARC research designs seem to be more suitable for this age group, including bilaterally presented stimuli (Zebian, 2005) and single-hand responses (Fischer, 2003). We adapted these methods in our task. Children were asked to point with the right hand to either the smaller or larger one of two sets of rectangles, displayed consecutively on both sides of the touch-screen computer display. The interaction consisting of shorter reaction times (RTs) for the “less” targets, displayed on the left side, and for the “more” targets, displayed on the right side, was regarded as an index of the spatial–numerical congruity (SNC) effect, which might be considered as analogous to the classical SNARC effect. To ascertain whether the performance of our participants was based on a nonverbal quantity estimation, we controlled the effect of ratio between the compared sets, which is the main signature of the analogue number system (Feigenson et al., 2004).
Section snippets
Participants
The participants were 96 children (mean age = 4 years 0 months (4;0), range = 2;8–4;11) from 10 preschools in Warsaw, Poland. An additional 35 children were tested but needed to be excluded (25 did not complete the task and 10 used the left hand or both hands; see correct procedure below). Written informed consent was obtained from all participants’ parents.
For the counting assessment, we adapted a Give-a-Number task (Wynn, 1990). The child was instructed to give a number of carrots to a toy dwarf.
Accuracy analyses
Correct responses constituted 87% of all choices made by participants. A 2 (CP Knowledge: CP-knowers or non-CP-knowers) × 3 (Ratio: 1:2, 2:3, or 3:4) analysis of variance (ANOVA), with repeated measures for ratio, was run on the proportions of correct answers, There were significant effects of CP knowledge, F(1, 94) = 15.56, p < .0002, η2p = .14, and ratio, F(1, 188) = 30.93, p < .0001, η2p = .25. CP-knowers gave more correct responses than precounting children (90% vs. 83%), and the correctness decreased
Discussion
Our experiment has documented an oriented spatial–numerical congruity effect in preschoolers with and without counting knowledge during a nonverbal numerosity comparison. It provided evidence that neither formal schooling (literacy and mathematics) nor a symbolic number format is indispensable in evoking directional spatial–numerical associations. Notably, the effect was already present and more consistent in precounting children. We also found size and ratio effects, providing evidence that
Acknowledgments
Authors are indebted to A. Otwinowska-Kasztelanic, A. Zevenbergen, H.-C. Nuerk, G. Wood, M. Fischer, and all reviewers for helpfull comments on earlier versions of this article. The study was supported from University of Warsaw research founds.
References (30)
Does the parietal cortex distinguish between “10”, “ten”, and ten dots?
Neuron
(2007)- et al.
Stimulus–response compatibility in representational space
Neuropsychologia
(1998) - et al.
Extracting parity and magnitude from Arabic numerals: Developmental changes in number processing and mental representation
Journal of Experimental Child Psychology
(1999) - et al.
Spontaneous mapping of number and space in adults and young children
Cognition
(2009) - et al.
Core systems of number
Trends in Cognitive Sciences
(2004) Finger counting habits modulate spatial–numerical associations
Cortex
(2008)- et al.
One, two, three, four, nothing more: An investigation of the conceptual sources of the verbal counting principles
Cognition
(2007) Neurocognitive start-up tools for symbolic number representations
Trends in Cognitive Sciences
(2010)- et al.
An effect of spatial–temporal association of response codes: Understanding the cognitive representations of time
Cognition
(2008) - et al.
Developing access to number magnitude: A study of the SNARC effect in 7- to 9-year-olds
Journal of Experimental Child Psychology
(2008)
Children’s understanding of counting
Cognition
Semantic congruity affects numerical judgments similarly in monkeys and humans
Proceedings of the National Academy of Sciences of the United States of America
Spontaneous analog number representations in 3-year-old children
Developmental Science
The mental representation of parity and number magnitude
Journal of Experimental Psychology: General
Number–space mapping in human infants
Psychological Science
Cited by (114)
Cognitive factors contribute to the symbolic and the non-symbolic SNARC effects in children and adults
2024, Cognitive DevelopmentDeveloping mental number line games to improve young children's number knowledge and basic arithmetic skills
2022, Journal of Experimental Child PsychologyChildren perform better on left than right targets in an ordinal task
2022, Acta PsychologicaToddlers' interventions toward fair and unfair individuals
2021, CognitionCitation Excerpt :To advance the question of whether infants engage in spontaneous punishment, we pioneered a novel procedure in which infants could enact reward or punishment using a touch screen. Touch screen devices have been successfully used for recording older children's responses (LoBue & DeLoache, 2007; Patro & Haman, 2012), for assessing infants' word comprehension (Friend & Keplinger, 2003; Hendrickson, Mitsven, Poulin-Dubois, Pascal, & Friend, 2015), visual search (Gerhardstein & Rovee-Collier, 2002), and as potential platforms for learning (Lytle, Garcia-Sierra, & Kuhl, 2018; Zack & Barr, 2016; Zack, Barr, Gerhardstein, Dickerson, & Meltzoff, 2009). However, counts of infants' screen touches have never been used as a dependent variable of interest to examine social interventions (see Frank, Sugarman, Horowitz, Lewis, & Yurovsky, 2016 and Lovato & Waxman, 2016 for reviews and discussion), adding to the novelty of the current approach.
Children's spatial–numerical associations on horizontal, vertical, and sagittal axes
2021, Journal of Experimental Child PsychologyCitation Excerpt :However, little is known about whether spatial–numerical associations exist on multiple axes during childhood. There is evidence to support the early emergence of a left-to-right-oriented mental number line in children as young as 3 years (Opfer & Thompson, 2006; Opfer et al., 2010; Patro & Haman, 2012). In addition, 4- to 7-year-olds demonstrate comparably accurate placement of number to position on both horizontally and vertically oriented scales (Simms, Muldoon & Towse, 2013), and magnitude-relevant horizontal SNARC effects have been detected in children as young as 5–7 years (Gibson & Maurer, 2016; Hoffmann et al., 2013; van Galen & Reitsma, 2008).