Comparing the Diadochokinetic Rate in Young and Elderly Persian Speakers

Objectives: Speech diadochokinesis (DDK) is defined as the ability to produce repetitive and fast oral movements. The aim of this study is to compare the DDK rate between young and elderly Persian adults. Methods: In this study, 244 normal adults (122 males and 122 females) were divided two groups: young people (aged 20-49) and elderly people(aged 50-69). Diadochokinesis was performed based on two ways: the participant was asked to  produce /pa/,/ta/,/ka/,/pata/,/paka/,/taka/, and /pataka/ sounds within a five seconds limit; and to repeat single syllable sounds (/pa/,/ta/,/ka/) 20 times, two syllables sounds (/pata/,/paka/,/taka/) 15 times, and a three syllables sound (/pataka/) ten times, separately and quickly. The independent T-test, one-way ANOVA, and Pearson correlation was used. Results: The results indicated a significant negative and weak correlation between age and all syllables in the specified time (range: -0.139 to -0.254), and a positive and weak correlation between age and time with respect to the repetition of all syllables (range: 0.121 to 0.245). There was no significant difference between genders in both ways (p > 0.05). Discussion:The results indicate difference DDK rate between the young and elderly people that can be used as a benchmark for the diagnosis of disabled individuals in producing repetitive and fast oral movements, as a base for clinical assessments.