Generative naming in normal aging: Total output and qualitative changes using phonemic and semantic constraints

Verbal fluency tasks are commonly used in the assessment of dementia, although less is known about fluency characteristics in normal aging individuals. Category and letter fluency tasks were administered to four groups of healthy subjects who ranged in age from 50 to 90 years (N = 174). Despite similar educational and vocabulary levels, significant group differences were found on the majority of category fluency tasks, but not in letter fluency. Qualitative analysis revealed that perseveration and intrusion errors were rare and not associated with age. In contrast, analysis of the hierarchical structure of one category fluency task demonstrated age-related differences. Older subjects produced fewer exemplars per subcategory, and generated more category names in relation to specific exemplars. Gender effects were minimal across tasks. Category fluency appears to be disproportionately reduced compared with letter fluency in normal aging, which would be consistent with some degradation of semantic memory systems.