Memory updating operation is highly correlated with multiplication performance

Although approximate number system (ANS) has widely seen as the key factor to predict math ability, we had recently found memory updating (continual adding and subtracting numbers) capacity to be a stronger predictor to multiplication performance. However, one could argue that these results were due to the similarity across two tasks as both memory updating and multiplication tasks required participants to be engaged in mathematic calculation. To examine this potential confound, we added three control conditions including (1) numerical memory updating task (remembering the larger number shown on screen, no addition and subtraction required), (2) word memory updating task (remembering the animal name that is smaller in size), (3) spatial memory updating task (remembering the spatial location after dot movements) in addition to (4) the original memory updating task, (5) an ANS task (select the panel with more dots) and (6) a multiplication task. Thirty-four college students were recruited to participate in all six tasks. Our preliminary results were consistent with previous findings that showed no correlations between ANS and multiplication task performance. Correlation between numerical memory updating and multiplication performance was relatively low, but performance in all the three other memory updating tasks was significantly correlated with performance in multiplication task (rs > 0.6), suggesting high correlations in performances we had found between memory updating and multiplication tasks was not due to the presence of numbers in both tasks. We therefore concluded that operation in memory updating was the key component to explain multiplication performance, not numbers per se.