Acoustic analyses of diadochokinesis in fluent and stuttering children.
OBJECTIVE
The purpose of the study was to acoustically compare the performance of children who do and do not stutter on diadochokinesis tasks in terms of syllable duration, syllable periods, and peak intensity.


METHODS
In this case-control study, acoustical analyses were performed on 26 children who stutter and 20 aged-matched normally fluent children (both groups stratified into preschoolers and school-aged children) during a diadochokinesis task: the repetition of articulatory segments through a task testing the ability to alternate movements. Speech fluency was assessed using the Fluency Profile and the Stuttering Severity Instrument.


RESULTS
The children who stutter and those who do not did not significantly differ in terms of the acoustic patterns they produced in the diadochokinesis tasks. Significant differences were demonstrated between age groups independent of speech fluency. Overall, the preschoolers performed poorer. These results indicate that the observed differences are related to speech-motor age development and not to stuttering itself.


CONCLUSIONS
Acoustic studies demonstrate that speech segment durations are most variable, both within and between subjects, during childhood and then gradually decrease to adult levels by the age of eleven to thirteen years. One possible explanation for the results of the present study is that children who stutter presented higher coefficients of variation to exploit the motor equivalence to achieve accurate sound production (i.e., the absence of speech disruptions).
Faculdade de Medicina da Universidade de São Paulo, Department of Physiotherapy, Speech-Language and Hearing Sciences and Occupational Therapy, São Paulo/SP, Brazil.
Fabiola Staróbole
FS
Juste
Silmara
S
Rondon
Fernanda Chiarion
FC
Sassi
Ana Paula
AP
Ritto
Claudia Aparecida
CA
Colalto
Claudia Regina Furquim de
CR
Andrade
D000367:Age Factors; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D011597:Psychomotor Performance; D013060:Speech / Q000502:physiology*; D013061:Speech Acoustics; D013067:Speech Perception / Q000502:physiology; D013068:Speech Production Measurement; D013342:Stuttering / Q000503:physiopathology*