Somjit Ruamsuk. Comparison study of acoustic analysis of maximum speech performance tasks between normal adult speakers and spastic dysarthria patients . Master's Degree(Communication Disorders). Mahidol University. : Mahidol University, 2003.
Comparison study of acoustic analysis of maximum speech performance tasks between normal adult speakers and spastic dysarthria patients
Abstract:
Acoustic analysis of maximum speech performance tasks (MPTs) evaluates
performance capabilities of various components in speech production mechanisms and provides useful
information about speech disorders. This study compared the acoustic analysis of MPTs in 30 Thai
spastic dysarthria patients and 30 Thai normal adult speakers. The normal adult speakers were matched
with spastic dysarthria patients relative to age and gender. There were 22 males and 8 females in each
group, ranging in age from 21 to 81 years. MPTs consisting of maximum sound prolongation (MSP),
fundamental frequency range (FFR) and maximum repetition rate (MRR) were administered to all
subjects by using acoustic analysis.
The study found that spastic dysarthria patients had 13 speech characteristic
abnormalities. There were strained-strangled voice, imprecise consonants, monoloudness, hypernasality,
slow rate, harsh voice, monopitch, vowel distortion, reduced stress, breathy voice, short phrase, low
pitch and pitch break.
In normal adult speakers, the MSP means were 13.21, 13.34, 14.08, 10.07, and 8.76
seconds for /a/, /u/, /i/, /s/, and /f/, respectively. The FFR mean was 33.36 semitones. The MRR means
were 6.38, 6.44, 6.16, 5.94, 5.93, and 6.55 syllables per second for /Pa/, /Ta/, /Ka/, /Sa/, /Fa/, and/ Pa-
Ta-Ka/, respectively. The results of MPTs in the normal group were within normal limits as defined by
Baken (2000). In spastic dysarthria patients, the MSP means were 6.13, 7.03, 7.29, 3.48, and 2.71
seconds for /a/, /u/, /i/, /s/, and /f/, respectively. The FFR mean was 23.36 semitones. The MRR means
were 4.38, 4.00, 3.50, 3.50, 3.77, and 3.74 syllables per second for /Pa/, /Ta, /Ka/, /Sa/, /Fa/, and /Pa -
Ta-Ka/, respectively. The results demonstrated that the MPTs of normal adult speakers were
significantly higher (p<0.05) than the spastic group on all tasks. The MPTs values of spastic dysarthria
patients were less than the MPTs values of normal adult speakers due to the neuromotor control deficits
associated with spastic dysarthria affecting a variety of speech components including respiration,
phonation, articulatory, resonatory and prosody mechanisms
The data from MPTs in the normal group could be used for guidelines in motor speech
evaluations. The performance on MPTs in spastic dysarthria could be used for guidelines for diagnosis
of spastic dysarthria and used as confirmation of the results of perceptual analysis.
Future studies should include other factors, which influence MPTs, such as severity
level or etiology of disease and should be focused on the correlation of age and gender in spastic
dysarthria patients. MPTs could be compared with normal groups between other types of dysarthria and
among types of dysarthria. The MPTs results could be used in studying speech characteristics in other
types of dysarthria.