Automatic activation of addition facts in arithmetic word problems.

Studies of mental arithmetic have shown that adults solve simple arithmetic problems by retrieving an answer automatically from a network of stored associations. However, most studies have been limited to single-digit addition and multiplication problems. In this article, we examine whether retrieval is also automatic in the context of more complex arithmetic tasks, such as arithmetic word problems. To test this hypothesis, we used a priming procedure with a target-naming task, in which the primes were the numbers included in two sentences containing the numerical information of an arithmetic word problem (e.g., 3 and 2 in "Joe had 3 marbles. Then Tom gave him 2 marbles"), and the targets were either congruent (e.g., 5) or incongruent (e.g., 8) with the prime. A neutral prime was also used replacing the numbers of the problem by capital letters (e.g., X and Y). Manipulating the relationship between the prime and the target and the duration of time that separates these two events, the overall results revealed shorter times in naming the congruent target than in a neutral condition and longer times in naming the incongruent target, even though mental arithmetic was completely irrelevant to the task. These results support the notion that automaticity of arithmetic-fact retrieval is not limited to simple addition, but it is also possible in other tasks, such as arithmetic word problems, which demand more cognitive resources than single-digit addition.