Comparative study of visual and verbal short-term memory in English and Spanish speakers: testing a linguistic hypothesis.

It has been proposed that differences in digit span performance between English and Spanish speakers are due to the greater number of syllables per digit in the Spanish language. To test this hypothesis, we studied the performance of 30 English- and 30 Spanish-speaking elders on the Wechsler Adult Intelligence Scale-Revised (WAIS-R) Digit Span Subtest, a modified digit span test that was linguistically comparable for both languages, and the Corsi Block Test. Consistent with previous reports, we found that English speakers scored significantly higher than Spanish speakers on WAIS-R Digit Span Forward. Group differences were reduced on the modified Digit Span Forward, but remained significant. English and Spanish speakers scored comparably on Digit Span Backward (WAIS-R and modified) and Visual Span. We suggest that although differences in the number of syllables per digit string are in part responsible for the lower performance of Spanish speakers on Digit Span Forward, cultural and educational issues also contribute to the observed differences between English and Spanish speakers.