Abstract

Objective: Verbal Fluencies (VF) animals (VFa) and VF fruits (VFf) have previously been described to be similarly effective in discriminating normal participants from patients with Alzheimer disease (AD). Both tasks were less accurate in discriminating AD-stages for unknown reasons. Based on semantic clustering scores in VFa, a literacy depending pattern has been revealed across cultures; however, no previous analysis has been performed for VFf. Methods: Three-hundred-fourteen native Brazilian Portuguese speakers were divided in four groups: a Control Group (CG) and Mild Cognitive Impairment (MCI), Mild Alzheimer’s Disease (MAD) and Moderate Alzheimer’s Disease (ModAD) groups. A quantitative (total score - TE) and a qualitative (clusters – Cf) analysis were conducted for VFf and were compared to other cognitive tasks. As no semantic setting was found, a non-arbitrary classification of fruits based on Sub Categorical items (Cf), according to the articulatory point of Brazilian Portuguese was performed. The words were grouped as follows: 1) bilabial, 2) velars, 3) open vowels, 4) closed vowels, 5) lateral dental/ alveolar, 6) dental /alveolar, and 7) labio-dentals. Clustering strategies (Cf) in the AD Groups differed from those of the CG. Cf revealed differences beyond groups depending on which articulatory point was emitted. Results: MCI had a 73% lower chance of attaining an NV than did the CG and with AD groups presented odds ratios of using the Cf /k/, /g/ velars feature 85% lower than those of the CG. Participants who used Cf bilabial had 2.04 times higher VFTE scores than those who did not. Younger subjects had a higher probability to perform better on the task. Participants with >9 years of education had a higher probability of higher performance with respect to the VFf TS. Conclusion: Articulatory deterioration occurred in AD since the early stages. VFf seems to be a suitable task for MCI evaluation.

Keywords: Neurodegeneration; Alzheimer’s disease; Neuropsychological tests; Cognitive assessment