Effects of bilingualism on verbal learning and memory in Hispanic adults.

The effect of bilingualism on qualitative aspects of verbal learning and memory was investigated. Equivalent list learning tests in English and Spanish were carefully constructed, and compared across two bilingual Hispanic groups of Mexican origin that differed in their level of English proficiency ("balanced" and "nonbalanced" bilinguals) and a group of monolingual English-speaking non-Hispanic subjects. Groups were matched for age, education, and gender composition. Nonbalanced bilinguals assessed in English utilized semantic clustering to the same extent as monolinguals, but learned fewer words overall, and demonstrated lower retention scores compared to monolinguals. Comparisons of groups assessed in their dominant languages, however, revealed no significant differences on any of the learning and memory indices examined. In addition to comparisons with standard clinical memory indices, assessment issues concerning bilingual individuals are addressed.