Comparing Verb Fluency With Verbal Fluency in Patients With Alzheimer's Disease

Abstract

Background: Alzheimer's disease (AD) is the most common type of dementia. Patients with AD have impaired semantic knowledge of nouns and verbs as well as the ability to verb retrieval. Objectives: The aim of this study was to compare verbal fluency and verb fluency and to investigate the association between severity and types of fluency (verbal-verb) in patients with AD. Patients and Methods: This cross-sectional study was performed on 30 patients (14 males, 16 females) with AD. The participants were assessed using the Mini Mental State Examination (MMSE) and a neurologist made the diagnosis of AD. In order to examine verb and verbal fluency, the subjects were asked to name any words that they remember in one minute. Scoring was based on the correct number of items and data analysis was performed by SPSS 16. Results: There was a significant positive correlation between letter fluency and verb fluency (P = 0.013), letter fluency and semantic fluency (P < 0.001), and verb fluency and semantic fluency (P = 0.002) in patients with AD. The results showed significant differences between letter fluency (P < 0.001), verb fluency (P = 0.034), and semantic fluency (P < 0.001) among patients with different severity of AD. In addition, the most frequently produced words in letter fluency were /a/, /s/, and /f/, consecutively. The mean ratio of semantic fluency to letter fluency was 3:5. Conclusions: In patients with AD, verb fluency was impaired more than semantic fluency was. Verb fluency task is an important criterion in diagnosis of early dementia. Therefore, the investigation of verb fluency in susceptible individuals with dementia might prevents the progression of the disorder.