Representing arithmetic table facts in memory: Evidence from acquired impairments

In this article we explore how arithmetic table facts (e.g., 6 × 9 = 54) are stored in memory and evaluate the possibility that arithmetic facts are exclusively stored in a phonological or sound-based form. We present two single-case studies of brain-damaged patients who suffer specific number processing impairments. Both patients often retrieve the correct answer to simple arithmetic problems from memory when unable to generate the phonological representation of either the arithmetic problem or the answer to that problem. We argue that this pattern of performance is incompatible with the hypothesis that arithmetic facts are stored and retrieved from memory exclusively in a phonological form. Accounts consistent with out findings are proposed.