A study of semantic and phonological verbal fluency in Alzheimer's disease

Alzheimer's disease (AD) is the leading cause of dementia in older adults, so early diagnosis is essential to slow or delay its progression. Among the cognitive markers of AD, verbal fluency seems to be an early indicator of deterioration. The main objective of the present work is to find out whether it is phonological or semantic verbal fluency that deteriorates earlier in AD. A Verbal Fluency Task was administered to 30 patients with AD and 30 control subjects matched by age, sex and educational level. On the one hand, statistically significant differences were found in the performance of the phonological fluency task between the control and experimental group, with better performance at higher educational level. On the other hand, in patients with AD it was observed that gender did not influence the performance of fluency tasks and, although performance in phonological fluency was slightly higher than in semantic fluency, no statistically significant differences were found. These results point to a possible greater impairment in phonological fluency in the early stages of AD that should be further analyzed in larger samples in order to be taken into account at the time of diagnosis.