Symbolic number processing and individual differences in adult’s arithmetic performance

Resumen

Recent work has shown that symbolic number processing relates to individual differences inarithmetic. However, it remains unclear what attributes of symbolic number processing (magnitudeprocessingor order processing) are crucial for success in mathematics. In the current study wequestion whether the relationship between symbolic number processing and mathematics achievementchanges as a result of the task used to assess math achievement by focusing on single-digit arithmetic(subtraction and multiplication). To address this question, adult participants performed a numeralordering task that relied on symbol-symbol associations (order processing)and a dots-number wordmatching task thought to be a measure of symbol-magnitude associations (magnitude processing). Thetasks were applied to university students, along with control tasks (intellectual ability, digit span,inhibitory control, non-numeric order processing, and general math achievement) and the arithmeticmeasures. Results showed that both magnitude processing and order processing tasks were uniquelyrelated to single-digit arithmetic achievement, although findings differed across the tasks used toassess arithmetic achievement. The regression analysis using multiplication performance as adependent variable was significant, F(9, 84) = 4.65, p < .0001, R2 = .33, and the experimentalmeasures accounted for an additional 12% of the variance, F(4, 84) = 3.84, p < .01, but numeralordering (ß = .43) was the only significant predictor. The model predicting subtraction performancewas also significant, F(9, 84) = 10.16, p < .0001, R2 = .52, and the experimental measures accountedfor an additional 11% of the variance, F(4, 84) = 4.66, p = .002. In this case, both numeral-ordering (ß= .26) and dots-number word matching (ß = .29) were significant predictors. The current studyprovides strong evidence for the idea that symbolic number processing plays a role in adults’ singledigit arithmetic. Nevertheless, findings also suggest that the mechanisms underlying symbolic numberprocessing can play a different role depending on the type of single-digit arithmetic skills, probablydue to demands involved in strategy use (direct memory retrieval vs. procedural strategies).