Age-related changes in category decision-making abilities as a function of typicality and animacy of noun exemplars

Abstract

Objectives: The current study investigated age-related changes in category decision-making abilities according to the semantic typicality and animacy of noun exemplars. Methods: A total of 60 participants participated in the study with 20 in each age group: Young, middle-aged, and elderly. A total of 140 stimuli were employed for the categorical decision-making task including animate (vegetables and animals) and inanimate (transportation and clothing) categories. Each semantic category contained either typical or atypical exemplars. Participants were instructed to quickly push a button to show which category the suggested words belonged to. Results: Participants showed more errors and slower RTs in the atypical than typical exemplars and in the inanimate than animate categories. There were significant interactions between typicality and animacy for both accuracy and RTs, indicating that atypical items of inanimate categories generated lower accuracy and longer RTs than the typical items of animate categories. There were significant interactions between typicality and age group for RTs; longer RTs were a function of typicality only for the elderly group. Conclusion: The current results suggested that semantic typicality of these noun exemplars are associated with age-related decline in cognitive processing speed. This data can be used for further investigation of stimuli development for naming treatment. © 2014 Korean Academy of Speech-Language Pathology and Audiology.