Verb naming and comprehension in patients with Alzheimer's Disease: Focusing on instrumentality of action verbs

Abstract

Objectives: The present study aimed to elucidate the nature of semantic impairment in action verbs focusing on instrumentality, as revealed in a verb naming and a comprehension tasks completed by healthy elderly and patients with Alzheimer's disease (AD). Methods: Twelve patients with mild and moderate AD and 12 healthy elderly participated in the study. Forty action verbs from 20 instrument verbs and 20 non-instrument verbs were selected for both confrontation naming and word-picture matching tasks. Task effect as well as semantic effect of instrument verbs was analyzed by using two-way mixed ANOVA and post-hoc analyses. Results: Verb naming and comprehension abilities in patients with AD were significantly poorer than healthy elderly. Unlike the healthy elderly, AD patients showed significantly lower naming scores for instrument verbs than for non-instrument verbs. Meanwhile, no instrumentality effect was found in the word-picture matching task for either group. Conclusion: These results confirm previous studies that report verb naming and comprehension deficits in patients with AD, and extend the finding to the semantic category of instrument verbs. Naming deficits in instrument verbs seem to be related to the loss of the semantic feature relationship between verbs and their corresponding nouns. The feature-based framework in semantic memory is discussed further. © 2017 Korean Academy of Speech-Language Pathology and Audiology.