Rate and Regularity of Articulatory Diadochokinetic Performance in Healthy Korean Elderly via Acoustic Analysis

Abstract

Aging is related to anatomical and physiological changes in respiratory and phonation organs. These changes influence articulation which leads to inaccurate speech and slow articulatory diadochokinesis(DDK). DDK indicates the range, rate, regularity, accuracy, and agility of articulation that reflect motor speech function. The purpose of this study is to investigate the rates and regularities of DDK in healthy Korean elderly through passive acoustic analysis (Praat). Thirty subjects between the ages of 65 and 94 participated in this study. Rate was observed for 5 seconds, while regularity was calculated based on the standard deviation on the following: 1) syllable duration of each task; 2) gap duration between syllables. Then, simple regression analysis was conducted in order to examine the effect of age on performance. The result showed that the slow rate was not a significant factor in terms of advancing age. Furthermore, regularity indicated a significant difference in the following: 1) /pʌ/, /kʌ/ and /pʌtʌkʌ/ in syllable duration; 2) /kʌ/ duration in the gap between syllables. In conclusion, articulatory coordination is reduced with the onset of aging. In particular, /kʌ/ would be a sensitive task for articulatory coordination.