Background: The precision of the articulatory movement and the coordination of tongue and jaw movements in children with cerebral palsy may be analysed acoustically by constructing the vowel space area. Even though some studies on vowel space area among children with cerebral palsy have been carried out, most of these studies are hardly conclusive. Further, the studies focusing on Indian disordered population are a handful.
Aim of the study: The present study aimed at investigating the difference across formant frequencies and vowel working space area between individuals with cerebral palsy and age-matched control subjects.
Method: Two groups of subjects were recruited for the study. Group 1 comprised of 20 individuals with cerebral palsy and group 2 comprised of 20 age-matched neurologically intact individuals. Phonation samples of vowels /a/, /i/ and /u/ was recorded and formant frequencies were extracted. Further, the Vowel Triangle Area was also calculated.
Results: The results showed that there was a significant difference in formant frequency values between the subjects of group 1 and group 2. It was also noted that the vowel space area entailing vowels /a/, /i/ and /u/ of group 1 individuals was significantly reduced when compared to group 2. Thus, the results demonstrated more restricted tongue movements in subjects of group 1.
Conclusion: Further studies ought to focus on the correlation of the reduced vowel space area and the speech intelligibility measures to assist the therapy to improve speech intelligibility in individuals with cerebral palsy.
Vowel space area, Formant frequencies, Cerebral palsy.