Verbal fluency in elderly bilingual speakers: normative data and preliminary application to Alzheimer's disease

This study investigated verbal fluency abilities in 30 healthy elderly English-Afrikaans bilingual speakers, and 6 bilingual subjects with Alzheimer's disease. Three 1-min semantic verbal fluency tasks (animals) were obtained in the bilingual mode, Afrikaans and English. Results were analysed in terms of total correct, and semantic clusters. There was no significant difference between monolingual and bilingual performance. Some healthy bilingual subjects used code switching as a strategy but with no direct increase in the number of exemplars generated, and there was no relationship between age of acquisition, pattern of use and verbal fluency scores. In comparison, subjects with Alzheimer's disease did not make use of code switching strategies, and there was some relationship between age of acquisition, pattern of use and verbal fluency scores.