- Email: [email protected]
number interference in a Piaget-like task
Cognitive Development 22 (2007) 124–129
Short communication
Negative priming effect after inhibition of weight/number interference in a Piaget-like task Olivier Schirlin, Olivier Houd´e ∗ UMR 6194, CNRS, CEA, Universities of Caen and Paris-5, France
Abstract Piagetian tasks have more to do with the child’s ability to inhibit interference than they do with the ability to grasp their underlying logic. Here we used a chronometric paradigm with 11-year-olds, who succeed in Piaget’s conservation-of-weight task, to test the role of cognitive inhibition in a priming version of this classical task. The experimental design was such that the misleading strategy “number-equals-weight” to inhibit on the prime (a Piaget-like item with weight/number interference) became a congruent strategy to activate on the probe (a subsequent item where weight and number covaried). A negative priming effect of 142 ms was observed for the prime-probe sequence. This result is consistent with the prediction that success on Piaget-like tasks (the prime) requires an inhibition process. © 2006 Published by Elsevier Inc. Keywords: Inhibition; Negative priming; Conservation task; Weight
To mesh better with new facts, Piaget’s (1984) theory needs to incorporate inhibition into each stage of cognitive development, from infancy to adulthood (Bjorklund & Harnishfeger, 1990; Dempster & Brainerd, 1995; Diamond & Gilbert, 1989; Diamond & Lee, 2000; Houd´e, 2000; Pascual-Leone, 1988). According to Dempster (1995), “Conservation and class inclusion [i.e., the famous Piagetian tasks] have more to do with the ability to resist interference than they do with the child’s ability to grasp their underlying logic.” (p. 15). In Piaget’s conservation-of-number task, for example, when shown two rows of objects containing the same number of objects but of different lengths (after the objects in one of the rows have been spread apart), the child has to say whether the two rows have the same number of objects (Piaget & Inhelder, 1969). Until the age of 7, children usually erroneously say there are more objects in the longer row. For Piaget, this means that children at this age have not yet reached the “number stage” (the concrete ∗ Correspondence to: UMR 6194, CNRS, CEA, Universit´ e Paris-5, Sorbonne, 46 rue Saint-Jacques, 75005 Paris, France. Tel.: +33 140462995; fax: +33 140462993. E-mail address: [email protected] (O. Houd´e).
0885-2014/$ – see front matter © 2006 Published by Elsevier Inc. doi:10.1016/j.cogdev.2006.06.003
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operations stage). Contrary to this view, it follows from Dempster’s interpretation that to succeed in Piaget’s task, the important thing is not being able to activate number capacities per se, but to inhibit a misleading strategy, namely the visuospatial “length-equals-number” strategy (an oftenrelevant quantification heuristic used by children and still used by adults) (Houd´e, 2000). To test this new interpretation, we previously used (Houd´e & Guichart, 2001) a chronometric paradigm with 9-year-olds (at the concrete operations stage) who succeed in the Piaget’s conservation-ofnumber task. The experimental design was a two-part, prime-probe numerical task, such that the misleading strategy “length-equals-number” that had to be inhibited on the prime (a Piaget-like item with number/length interference) became a congruent strategy to activate on the probe (a subsequent item where number and length covaried). According to Tipper’s (1985) interpretation (knowing that conflicting views exist: see Tipper, 2001, for a review), if the misleading strategy is inhibited when the prime appears, then activating the same strategy on the probe should set off a negative priming effect (i.e., a longer response time).1 Indeed, a negative priming effect was observed for the prime-probe sequence, compared to a control condition. This result is consistent with the prediction that success on Piaget-like tasks requires an inhibition process. In order to generalize this first result, here we reused the same experimental design with a Piaget’s conservation-of-weight task, which is – following Piaget’s terminology – from the “infra-logic” domain (i.e., continuous contents: weight, liquids, mass, and length), contrasted with the “logic” domain (i.e., discontinuous contents: number). Remember that according to Piaget, children are not able to reason correctly about weight conservation until the age of 10 (thus with a discrepancy regard to number conservation during the concrete operations stage) (Piaget & Inhelder, 1969). When shown two displays of objects containing the same quantity of substance, and consequently the same weight, but of different number (for example, one big ball and three small balls), the child has to say whether the two displays have the same weight. Until the age of 10, children usually erroneously say that the three-balls display is heavier than the one-ball display. Here again, we hypothesize that to succeed in this Piaget’s task, the child has to inhibit the misleading “number-equals-weight” strategy. To test this new interpretation, we reused our chronometric paradigm (Houd´e & Guichart, 2001) with 11-year-olds who succeed in the Piaget’s conservation-of-weight task. The experimental design was a two-part, prime-probe task, such that the misleading strategy “number-equalsweight” that had to be inhibited on the prime (a Piaget-like item with weight/number interference) became a congruent strategy to activate on the probe (a subsequent item where weight and number covaried). According to Tipper’s (1985) interpretation, if the misleading strategy is inhibited when the prime appears, then activating the same strategy on the probe should set off a negative priming effect, i.e., a longer response time. Note that, by definition, the negative priming paradigm can only test for inhibition if the child succeeds on the preceding interference item (here, the Piaget-like item). The idea is to find out whether or not the child used inhibition to succeed on the prime, by measuring the priming effect on the probe. Contrary to the customary procedure in child psychology, it is not failure on the task that is analyzed here (in which case we would have studied younger children using another method) but success. Note also that the task we used was not a conservation task in the strict Piaget sense (where there is transformation of one of two displays), but a weight/number interference task where children 1 Initially, Tipper’s negative priming paradigm was defined in terms of stimuli, with a target stimulus to be processed and a distractor stimulus to be ignored (or inhibited). The present setup is a variation applied to cognitive strategies activation/inhibition (like in Houd´e & Guichart’s (2001) paper prereviewed by Steve Tipper).
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had to judge the weight equivalence of a static pair of scales. In the computerized procedure we developed to test for negative priming (a chronometry procedure), static displays had to be used. Had we used a judgment about the Initial state (I = two identical objects), a transformation (modify one object), and then a judgment about the Final state (F) (as Piaget would have done), we could not have measured the priming effect in F between items (prime-probe sequence), since the initial judgment (I) of the probe would have occurred in the interim. It is still relevant to speak of a “Piaget-like” task (following Houd´e & Guichart, 2001), though, because the prime tests the child’s ability to respond to the dimension of weight independently of any irrelevant perceptual cues (number of objects), which is the Piagetian aim of this type of task. 1. Experimental design and results 1.1. Participants We tested 38 sixth graders from two schools in Franche-Comte, France (mean age 11.4). 1.2. Stimuli and procedure Each child was tested individually in one session consisting of eight pairs of items, four for the test condition (negative priming) and four for the control condition (16 items). An item was presented on a computer screen showing a pair of scales on which two displays of objects were placed (see Fig. 1). These displays composed of sets of rectangles could be of equal or different weight, and the children had to judge their weight equivalence. The two displays could include different number of rectangles of different sizes: for example, one big rectangle and two small rectangles of equal weight (that is a Piaget-like item with weight/number interference). Children were instructed to respond by pressing the “same-weight” button or the “not-sameweight” button as quickly as possible, without making any errors. When a button was pressed, the computer recorded the child’s response time (RT) (measured in milliseconds since stimulus onset) and displayed the next item, at an inter-stimulus interval of 1500 ms. A familiarization session was provided using a real pair-of-scales system. After familiarization, the number of errors was insignificant (less than 5%). In the test condition, the four pairs (prime-probe) of items were constructed in such a way that the misleading or incongruent strategy to inhibit in A (the numberequals-weight strategy) became a congruent strategy in B. A was thus a Piaget-like item with weight/number interference, while B was a subsequent item where weight and number covaried (for example, a two-rectangles display which was logically heavier than a one-rectangle display). In the control condition the item presentation order was reversed (B then A). The four test pairs (A then B) and the four control pairs (B then A) were distributed randomly. Between each pair, a neutral item was introduced: a pair of scales on which two identical displays of objects were placed (for example, two pentagons), ruling out the number-equals-weight strategy. The answer to the neutral items was always “same-weight,” generating the same output conditions as in A on a test pair. With this experimental design, our aim was to compare RT on B in the test condition (A then B) to RT on B in the control condition (B then A), that is, by hypothesis, with or without previous inhibition of the number-equals-weight strategy. The entire set of stimuli was as follows (a randomly ordered A–B sequence is given here): (1) one big rectangle and two small rectangles of equal weight for A; two big rectangles and one big rectangle of different weight for B; (2) two big rectangles and four small rectangles of equal weight
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Fig. 1. Experimental design and results. An item was presented on a computer screen showing a pair of scales on which two displays of objects were placed. The children had to judge their weight equivalence. They were instructed to respond by pressing the “same-weight” button or the “not-same-weight” button as quickly as possible, without making any errors. When a button was pressed, the computer recorded the child’s response time (RT) (measured in milliseconds since stimulus onset) and displayed the next item. In the test condition, the four pairs (prime-probe) of items were constructed in such a way that the misleading or incongruent strategy (S2) to inhibit in A (the number-equals-weight strategy) became a congruent strategy in B (S1 was the conservation-of-weight strategy to activate in A). A was thus a Piaget-like item with weight/number interference, while B was a subsequent item where weight and number covaried. In the control condition the item presentation order was reversed (B then A).
for A; four small rectangles and one big rectangle of different weight for B; (3) one big rectangle and four small rectangles of equal weight for A; three small rectangles and one big rectangle of different weight for B; (4) two small rectangles and one big rectangle of equal weight for A; five small rectangles and two small rectangles of different weight for B. Other combinations of numbers and sizes were obviously possible. Our main purpose was that in each A–B pairs, A was a weight/number interference item (the number of rectangles was different but their weight was systematically equal), while B was a weight-number covariation item (the numbers of rectangles
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were different and, consequently, the weights of the displays were also different: for example, the two-big-rectangles display was heavier than the one-big-rectangle display). 1.3. Results For the statistical analysis of RT, children whose RT was more than 2.5 standard deviations away from the group mean in the test or control condition were excluded (three children). The results indicated a mean RT on B of 1845 ms in the test condition and 1703 ms in the control condition (see Fig. 1). Thus, a negative priming effect of 142 ms was observed. The difference was significant (t(34) = 2.34, p < 0.02). 2. Discussion This chronometric result shows that a weight/number interference task like Piaget’s (the prime in our procedure) tests children’s inhibitory efficiency (hence, the negative priming effect observed on the probe). Note that the experimental design was such that the observed result, i.e., negative priming on B for test pairs (A then B), cannot be accounted for by positive priming on B for control pairs (B then A). All pairs were separated by a neutral item, which ruled out using the numberequals-weight strategy (making positive priming impossible in this strategy at the beginning of a control pair). In addition, as stated above, the answer to the neutral item was always “sameweight,” generating the same output conditions as in A on a test pair (so, no positive priming on the response either). Thus, the observed negative priming effect does indeed argue for Dempster’s (1995) claim that Piagetian conservation tasks have first and foremost to do with the child’s ability to resist (inhibit) interference (here, the weight/number interference). Hence, this new result generalizes in the “infra-logic” domain (i.e., continuous contents like weight) our previous result obtained in the “logic” domain (i.e., discontinuous contents: number) (Houd´e & Guichart, 2001), confirming that to mesh better with new facts, Piaget’s theory needs to incorporate inhibition into each stage of cognitive development. This approach fits well with the recent brain imaging literature on child development (Casey, Tottenham, Liston, & Durston, 2005) showing that brain regions associated with basic functions such as sensory and motor processes mature first, followed by association areas involved in top-down control of cognition, such as inhibitory control. References Bjorklund, D., & Harnishfeger, K. (1990). The resources construct in cognitive development: Diverse sources of evidence and a theory of inefficient inhibition. Developmental Review, 7, 93–130. Casey, B. J., Tottenham, N., Liston, C., & Durston, S. (2005). Imaging the developing brain. Trends in Cognitive Sciences, 9, 104–110. Dempster, F. (1995). Interference and inhibition in cognition: An historical perspective. In F. Dempster & C. Brainerd (Eds.), Interference and inhibition in cognition (pp. 3–26). New York: Academic Press. Dempster, F., & Brainerd, C. (1995). Interference and inhibition in cognition. New York: Academic Press. Diamond, A. (1991). Neuropsychological insights into the meaning of object concept development. In S. Carey & R. Gelman (Eds.), The epigenesis of mind: Essays on biology and cognition (pp. 67–110). Hillsdale, NJ: Erlbaum. Diamond, A. (2002). Normal development of prefrontal cortex from birth to young adulthood: Cognitive functions, anatomy, and biochemistry. In D. Stuss & R. Knight (Eds.), Principles of frontal lobe function (pp. 466–503). London: Oxford University Press. Diamond, A., & Gilbert, J. (1989). Development as progressive inhibitory control of action. Cognitive Development, 4, 223–249.
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Diamond, A., & Lee, E.-Y. (2000). Inability of 5-month-old infants to retrieve a contiguous object: A failure of conceptual understanding or of control of action? Child Development, 71, 1477–1494. Houd´e, O. (2000). Inhibition and cognitive development: Object, number, categorization, and reasoning. Cognitive Development, 15, 63–73. Houd´e, O., & Guichart, E. (2001). Negative priming effect after inhibition of number/length interference in a Piaget-like task. Developmental Science, 4, 71–74. Pascual-Leone, J. (1988). Organismic processes for neo-Piagetian theories. In A. Demetriou (Ed.), The Neo-Piagetian theories of cognitive development (pp. 25–64). Amsterdam: North-Holland. Piaget, J. (1984). Piaget’s theory. In P. Mussen (Ed.), Handbook of child psychology: Vol. 1, (pp. 103–128). New York: Wiley. Piaget, J., & Inhelder, B. (1969). The psychology of the child. New York: Basic Books. Tipper, S. (1985). The negative priming effect: Inhibitory priming by ignored objects. Quarterly Journal of Experimental Psychology, 37, 571–590. Tipper, S. (2001). Does negative priming reflect inhibitory mechanisms? A review and integration of conflicting views. Quarterly Journal of Experimental Psychology, 54, 321–343.
Short communication
Negative priming effect after inhibition of weight/number interference in a Piaget-like task Olivier Schirlin, Olivier Houd´e ∗ UMR 6194, CNRS, CEA, Universities of Caen and Paris-5, France
Abstract Piagetian tasks have more to do with the child’s ability to inhibit interference than they do with the ability to grasp their underlying logic. Here we used a chronometric paradigm with 11-year-olds, who succeed in Piaget’s conservation-of-weight task, to test the role of cognitive inhibition in a priming version of this classical task. The experimental design was such that the misleading strategy “number-equals-weight” to inhibit on the prime (a Piaget-like item with weight/number interference) became a congruent strategy to activate on the probe (a subsequent item where weight and number covaried). A negative priming effect of 142 ms was observed for the prime-probe sequence. This result is consistent with the prediction that success on Piaget-like tasks (the prime) requires an inhibition process. © 2006 Published by Elsevier Inc. Keywords: Inhibition; Negative priming; Conservation task; Weight
To mesh better with new facts, Piaget’s (1984) theory needs to incorporate inhibition into each stage of cognitive development, from infancy to adulthood (Bjorklund & Harnishfeger, 1990; Dempster & Brainerd, 1995; Diamond & Gilbert, 1989; Diamond & Lee, 2000; Houd´e, 2000; Pascual-Leone, 1988). According to Dempster (1995), “Conservation and class inclusion [i.e., the famous Piagetian tasks] have more to do with the ability to resist interference than they do with the child’s ability to grasp their underlying logic.” (p. 15). In Piaget’s conservation-of-number task, for example, when shown two rows of objects containing the same number of objects but of different lengths (after the objects in one of the rows have been spread apart), the child has to say whether the two rows have the same number of objects (Piaget & Inhelder, 1969). Until the age of 7, children usually erroneously say there are more objects in the longer row. For Piaget, this means that children at this age have not yet reached the “number stage” (the concrete ∗ Correspondence to: UMR 6194, CNRS, CEA, Universit´ e Paris-5, Sorbonne, 46 rue Saint-Jacques, 75005 Paris, France. Tel.: +33 140462995; fax: +33 140462993. E-mail address: [email protected] (O. Houd´e).
0885-2014/$ – see front matter © 2006 Published by Elsevier Inc. doi:10.1016/j.cogdev.2006.06.003
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operations stage). Contrary to this view, it follows from Dempster’s interpretation that to succeed in Piaget’s task, the important thing is not being able to activate number capacities per se, but to inhibit a misleading strategy, namely the visuospatial “length-equals-number” strategy (an oftenrelevant quantification heuristic used by children and still used by adults) (Houd´e, 2000). To test this new interpretation, we previously used (Houd´e & Guichart, 2001) a chronometric paradigm with 9-year-olds (at the concrete operations stage) who succeed in the Piaget’s conservation-ofnumber task. The experimental design was a two-part, prime-probe numerical task, such that the misleading strategy “length-equals-number” that had to be inhibited on the prime (a Piaget-like item with number/length interference) became a congruent strategy to activate on the probe (a subsequent item where number and length covaried). According to Tipper’s (1985) interpretation (knowing that conflicting views exist: see Tipper, 2001, for a review), if the misleading strategy is inhibited when the prime appears, then activating the same strategy on the probe should set off a negative priming effect (i.e., a longer response time).1 Indeed, a negative priming effect was observed for the prime-probe sequence, compared to a control condition. This result is consistent with the prediction that success on Piaget-like tasks requires an inhibition process. In order to generalize this first result, here we reused the same experimental design with a Piaget’s conservation-of-weight task, which is – following Piaget’s terminology – from the “infra-logic” domain (i.e., continuous contents: weight, liquids, mass, and length), contrasted with the “logic” domain (i.e., discontinuous contents: number). Remember that according to Piaget, children are not able to reason correctly about weight conservation until the age of 10 (thus with a discrepancy regard to number conservation during the concrete operations stage) (Piaget & Inhelder, 1969). When shown two displays of objects containing the same quantity of substance, and consequently the same weight, but of different number (for example, one big ball and three small balls), the child has to say whether the two displays have the same weight. Until the age of 10, children usually erroneously say that the three-balls display is heavier than the one-ball display. Here again, we hypothesize that to succeed in this Piaget’s task, the child has to inhibit the misleading “number-equals-weight” strategy. To test this new interpretation, we reused our chronometric paradigm (Houd´e & Guichart, 2001) with 11-year-olds who succeed in the Piaget’s conservation-of-weight task. The experimental design was a two-part, prime-probe task, such that the misleading strategy “number-equalsweight” that had to be inhibited on the prime (a Piaget-like item with weight/number interference) became a congruent strategy to activate on the probe (a subsequent item where weight and number covaried). According to Tipper’s (1985) interpretation, if the misleading strategy is inhibited when the prime appears, then activating the same strategy on the probe should set off a negative priming effect, i.e., a longer response time. Note that, by definition, the negative priming paradigm can only test for inhibition if the child succeeds on the preceding interference item (here, the Piaget-like item). The idea is to find out whether or not the child used inhibition to succeed on the prime, by measuring the priming effect on the probe. Contrary to the customary procedure in child psychology, it is not failure on the task that is analyzed here (in which case we would have studied younger children using another method) but success. Note also that the task we used was not a conservation task in the strict Piaget sense (where there is transformation of one of two displays), but a weight/number interference task where children 1 Initially, Tipper’s negative priming paradigm was defined in terms of stimuli, with a target stimulus to be processed and a distractor stimulus to be ignored (or inhibited). The present setup is a variation applied to cognitive strategies activation/inhibition (like in Houd´e & Guichart’s (2001) paper prereviewed by Steve Tipper).
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had to judge the weight equivalence of a static pair of scales. In the computerized procedure we developed to test for negative priming (a chronometry procedure), static displays had to be used. Had we used a judgment about the Initial state (I = two identical objects), a transformation (modify one object), and then a judgment about the Final state (F) (as Piaget would have done), we could not have measured the priming effect in F between items (prime-probe sequence), since the initial judgment (I) of the probe would have occurred in the interim. It is still relevant to speak of a “Piaget-like” task (following Houd´e & Guichart, 2001), though, because the prime tests the child’s ability to respond to the dimension of weight independently of any irrelevant perceptual cues (number of objects), which is the Piagetian aim of this type of task. 1. Experimental design and results 1.1. Participants We tested 38 sixth graders from two schools in Franche-Comte, France (mean age 11.4). 1.2. Stimuli and procedure Each child was tested individually in one session consisting of eight pairs of items, four for the test condition (negative priming) and four for the control condition (16 items). An item was presented on a computer screen showing a pair of scales on which two displays of objects were placed (see Fig. 1). These displays composed of sets of rectangles could be of equal or different weight, and the children had to judge their weight equivalence. The two displays could include different number of rectangles of different sizes: for example, one big rectangle and two small rectangles of equal weight (that is a Piaget-like item with weight/number interference). Children were instructed to respond by pressing the “same-weight” button or the “not-sameweight” button as quickly as possible, without making any errors. When a button was pressed, the computer recorded the child’s response time (RT) (measured in milliseconds since stimulus onset) and displayed the next item, at an inter-stimulus interval of 1500 ms. A familiarization session was provided using a real pair-of-scales system. After familiarization, the number of errors was insignificant (less than 5%). In the test condition, the four pairs (prime-probe) of items were constructed in such a way that the misleading or incongruent strategy to inhibit in A (the numberequals-weight strategy) became a congruent strategy in B. A was thus a Piaget-like item with weight/number interference, while B was a subsequent item where weight and number covaried (for example, a two-rectangles display which was logically heavier than a one-rectangle display). In the control condition the item presentation order was reversed (B then A). The four test pairs (A then B) and the four control pairs (B then A) were distributed randomly. Between each pair, a neutral item was introduced: a pair of scales on which two identical displays of objects were placed (for example, two pentagons), ruling out the number-equals-weight strategy. The answer to the neutral items was always “same-weight,” generating the same output conditions as in A on a test pair. With this experimental design, our aim was to compare RT on B in the test condition (A then B) to RT on B in the control condition (B then A), that is, by hypothesis, with or without previous inhibition of the number-equals-weight strategy. The entire set of stimuli was as follows (a randomly ordered A–B sequence is given here): (1) one big rectangle and two small rectangles of equal weight for A; two big rectangles and one big rectangle of different weight for B; (2) two big rectangles and four small rectangles of equal weight
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Fig. 1. Experimental design and results. An item was presented on a computer screen showing a pair of scales on which two displays of objects were placed. The children had to judge their weight equivalence. They were instructed to respond by pressing the “same-weight” button or the “not-same-weight” button as quickly as possible, without making any errors. When a button was pressed, the computer recorded the child’s response time (RT) (measured in milliseconds since stimulus onset) and displayed the next item. In the test condition, the four pairs (prime-probe) of items were constructed in such a way that the misleading or incongruent strategy (S2) to inhibit in A (the number-equals-weight strategy) became a congruent strategy in B (S1 was the conservation-of-weight strategy to activate in A). A was thus a Piaget-like item with weight/number interference, while B was a subsequent item where weight and number covaried. In the control condition the item presentation order was reversed (B then A).
for A; four small rectangles and one big rectangle of different weight for B; (3) one big rectangle and four small rectangles of equal weight for A; three small rectangles and one big rectangle of different weight for B; (4) two small rectangles and one big rectangle of equal weight for A; five small rectangles and two small rectangles of different weight for B. Other combinations of numbers and sizes were obviously possible. Our main purpose was that in each A–B pairs, A was a weight/number interference item (the number of rectangles was different but their weight was systematically equal), while B was a weight-number covariation item (the numbers of rectangles
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were different and, consequently, the weights of the displays were also different: for example, the two-big-rectangles display was heavier than the one-big-rectangle display). 1.3. Results For the statistical analysis of RT, children whose RT was more than 2.5 standard deviations away from the group mean in the test or control condition were excluded (three children). The results indicated a mean RT on B of 1845 ms in the test condition and 1703 ms in the control condition (see Fig. 1). Thus, a negative priming effect of 142 ms was observed. The difference was significant (t(34) = 2.34, p < 0.02). 2. Discussion This chronometric result shows that a weight/number interference task like Piaget’s (the prime in our procedure) tests children’s inhibitory efficiency (hence, the negative priming effect observed on the probe). Note that the experimental design was such that the observed result, i.e., negative priming on B for test pairs (A then B), cannot be accounted for by positive priming on B for control pairs (B then A). All pairs were separated by a neutral item, which ruled out using the numberequals-weight strategy (making positive priming impossible in this strategy at the beginning of a control pair). In addition, as stated above, the answer to the neutral item was always “sameweight,” generating the same output conditions as in A on a test pair (so, no positive priming on the response either). Thus, the observed negative priming effect does indeed argue for Dempster’s (1995) claim that Piagetian conservation tasks have first and foremost to do with the child’s ability to resist (inhibit) interference (here, the weight/number interference). Hence, this new result generalizes in the “infra-logic” domain (i.e., continuous contents like weight) our previous result obtained in the “logic” domain (i.e., discontinuous contents: number) (Houd´e & Guichart, 2001), confirming that to mesh better with new facts, Piaget’s theory needs to incorporate inhibition into each stage of cognitive development. This approach fits well with the recent brain imaging literature on child development (Casey, Tottenham, Liston, & Durston, 2005) showing that brain regions associated with basic functions such as sensory and motor processes mature first, followed by association areas involved in top-down control of cognition, such as inhibitory control. References Bjorklund, D., & Harnishfeger, K. (1990). The resources construct in cognitive development: Diverse sources of evidence and a theory of inefficient inhibition. Developmental Review, 7, 93–130. Casey, B. J., Tottenham, N., Liston, C., & Durston, S. (2005). Imaging the developing brain. Trends in Cognitive Sciences, 9, 104–110. Dempster, F. (1995). Interference and inhibition in cognition: An historical perspective. In F. Dempster & C. Brainerd (Eds.), Interference and inhibition in cognition (pp. 3–26). New York: Academic Press. Dempster, F., & Brainerd, C. (1995). Interference and inhibition in cognition. New York: Academic Press. Diamond, A. (1991). Neuropsychological insights into the meaning of object concept development. In S. Carey & R. Gelman (Eds.), The epigenesis of mind: Essays on biology and cognition (pp. 67–110). Hillsdale, NJ: Erlbaum. Diamond, A. (2002). Normal development of prefrontal cortex from birth to young adulthood: Cognitive functions, anatomy, and biochemistry. In D. Stuss & R. Knight (Eds.), Principles of frontal lobe function (pp. 466–503). London: Oxford University Press. Diamond, A., & Gilbert, J. (1989). Development as progressive inhibitory control of action. Cognitive Development, 4, 223–249.
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Diamond, A., & Lee, E.-Y. (2000). Inability of 5-month-old infants to retrieve a contiguous object: A failure of conceptual understanding or of control of action? Child Development, 71, 1477–1494. Houd´e, O. (2000). Inhibition and cognitive development: Object, number, categorization, and reasoning. Cognitive Development, 15, 63–73. Houd´e, O., & Guichart, E. (2001). Negative priming effect after inhibition of number/length interference in a Piaget-like task. Developmental Science, 4, 71–74. Pascual-Leone, J. (1988). Organismic processes for neo-Piagetian theories. In A. Demetriou (Ed.), The Neo-Piagetian theories of cognitive development (pp. 25–64). Amsterdam: North-Holland. Piaget, J. (1984). Piaget’s theory. In P. Mussen (Ed.), Handbook of child psychology: Vol. 1, (pp. 103–128). New York: Wiley. Piaget, J., & Inhelder, B. (1969). The psychology of the child. New York: Basic Books. Tipper, S. (1985). The negative priming effect: Inhibitory priming by ignored objects. Quarterly Journal of Experimental Psychology, 37, 571–590. Tipper, S. (2001). Does negative priming reflect inhibitory mechanisms? A review and integration of conflicting views. Quarterly Journal of Experimental Psychology, 54, 321–343.