Analyzing acoustic features of front plosive stop sounds of children with hypernasality

Cleft Lip Palate (CLP) is a congentinal defect. People with CLP have feeding, dental, hearing, physical appearance and speech problems. Individuals with CLP have also problems with producing obstruent sounds. In their speech, it is known plosive and fricative sounds are weakened. This has an impact on Voice Onset Time (VOT). VOT is defined as the length of time that passes between the release of a stop consonant and the onset of voicing. The aim of this study is to analyze acoustic features of front plosive stop sounds of children with hypernasality. In this study, target front plosive stop sounds‟ (/p, b, t, d/) duration, burst duration and stop duration are examined. As front plosive stop sounds are located in the sentences, participants are asked to read them. 2 groups are consisted of 6 children with CLP with hypernasality and 6 children with typical development in total twelve (6 male, 6 female). All of the particapants were Turkish native speakers whose ages were between 10-12. As to statistics, Open Source Statistics Software R was utilized. In this software, linear mixed effects model was adopted. As a result of this study; it is seen target sounds‟ duration is longer for children with hypernasality. Additionally; it is determined that target sounds‟ burst duration is longer in this group. Besides, participants with hypernasality has a longer prolonged stop duration. Finally, it is found compared to children with hypernasality; VOT duration is shorter in children without hypernasality. It is shown that hypernasality has an effect on front plosive stop sounds‟ duration, burst duration and stop duration. Keywords: Hypernasality, cleft lip palate, front plosive sounds, VOT