[ investigation of the effect of nasalization on /a/ vowel frequency formants before and after /m/ nasal consonant in cleft palate children]

Velopharyngeal coarticulation refers to the influence of a nasal consonant on preceding segments or the following segments during continuous speech. Coupling of the nasal resonating space to the oropharyngeal cavity alters the vocal tract formants in complex ways. The purpose of this study was to investigate the effect of nasal coarticulation and /a/ vowel frequency formants in cleft palate Persian speaking children. In present cross-sectional study, voice samples of 30 cleft palate children ranging 4-12 years were investigated. Participants were asked to repeat /ama/ three times and vowel /a/ after presentation of an auditory model. Afterwards, obtained samples were analyzed using Praat [version 5.3.13] software. Investigating the effect of nasalization on formants of /a/ vowel before and after nasal consonant and comparing with single prolonged /a/, "Bi-variate analysis of variance test" were used. There were no significant differences of fundamental frequency [F0] between /a/ which proceeds nasal consonant and /a/ follows nasal consonant, the before nasal consonant /a/ versus single /a/ and the after nasal consonant /a/ versus single /a/ in normal and cleft palate children [P>0.05]. However, findings revealed statistically significant differences of first, second and third formants [F1, F2, F3] between three situations [p<0.001]. In the cleft palate children, F1, F2, F3 in /a/ before nasal consonant affected by anticipatory nasal coarticulation and in /a/ after nasal consonant affected by carry-over nasal coarticulation. This study showed nasal coarticulation and nasalization result in decreasing F1, F2, F3 in /a/ vowel

[Intonation and duration curve in Persian interrogative sentences]

Prosody is a very important factor in communication and includes such parameters as: duration, intonation, pitch, stress, rhythm etc. Intonation is the pitch variation in one sentence. Duration is the time taken to utter a voice. The aim of the present study was to evaluate some parameters of prosody such as duration and intonation curve in interrogative sentences among normal Farsi speaking adults in order to determine the characteristics of this aspect of language with an emphasis on laboratory testing. This study was performed as a cross-sectional one. The participants included 134 male and female Farsi speaking individuals aging between 18-30 years. In this study two interrogative sentences with open and closed answers were used. The voice samples were analyzed by Dr. speech -real analysis software. Data analysis incorporated unilateral analysis of variance and an intonation curve was drawn for each sentence. The parameter of duration among men and women was significantly different [p

[Comparing of two Farsi passages in laboratory evaluation of mean and fundamental frequency variations range]

Voice disorders assess with the help of laboratory equipments and perceptual evaluation. Voice samples involve vowel prolongation, text-reading or conversational speech. In Iran, Rainbow text and Grandfather text, were developed for assessing voice. This study was cross-sectional and descriptive-analytical. Mean and fundamental frequency variations range in 120 normal males and females aging from 20-59 years old were studied. Voice samples of reading both texts were gathered and compared. Mean fundamental frequency in males in Grandfather text was 137.93 with SD 1.2 and in Rainbow text was 135.09 with SD 1.1 [p>0.05], in females Grandfather and Rainbow texts were 206.07 with SD 0.9 and 204.23 with SD 2.1, respectively [p>0.05]. Fundamental frequency variations range in Grandfather text in males was 88.10 with SD 0.8 and in females was 116.77 with SD 1.3 and in Rainbow text in males was 90.92 with SD 1.1, in females was 116.08 with SD 1.2 [p>0.05]. Mean fundamental frequency of males in each text didn't show significant difference in age groups and just in 50-59 age group of the female population showed significant difference. Fundamental frequency variations range didn't show significant difference in males and females in both texts. These two texts were the same in measurement of average and fundamental frequency variations range in adults. Significant difference showed between 50-59 age group of the female population and other groups

[Formant structure and vowel space in Persian vowels]

Formant structure and vowel space are the most important acoustic characteristics of speech sounds. The purpose of this study was to determine formant frequency and vowel space in six Persian vowels. This cross-sectional descriptive-analytic study was performed on 60 Persian students of Tehran University of Medical Sciences [30 males, 30 females] with their age ranging from 18 to 24 years. The subject articulated six Persian vowels in isolation and data was recorded by real-analyzer software. Then, the first three formant frequency of each vowel was determined for each subject. Vowel formant frequency averages were measured separately for each vowel and each gender. Vowel space was plotted. The difference between F0 in two groups was compared by Leven and independent sample t tests. Maximum and minimum values of F0 in both group was related to /‘/ and /a/ [135 Hz in males and 239 Hz in females] and /i/ [146 Hz in males and 239 Hz in females]. Besides, F0 in females was significantly higher than males [p<0.001]. Maximum and minimum values of F1 were related to /‘/ and /i/. Furthermore, maximum and minimum values of F[2] were related to /i/ and /u/. Maximum and minimum values of F[3] were related to /i/ and /u/. The lowest vowels were /‘/ and /a/ and the highest was /i/. The frontest was /i/ and the backest was /u/. The spreadest vowel was /i/ and the roundest was /u/