چكيده فارسي :
هدف از اين تحقيق مقايسه فضاي واكه اي كودكان داراي سمعك، كودكان كاشت حلزون شنوايي و كودكان بدون اختلال شنوايي با توجه به متغير هاي اختلال شنوايي و جنسيت است. از سي كودك، ده كودك در هر گروه كه شامل پنج دختر و پنج پسر بودند، خواسته شد تا 36 كلمه با ساختار CVC را كه متشكل از همخوان هاي انسدادي آغازه و پايانه يكسان و واكه هاي زبان فارسي بودند تكرار كنند. كلمات موردنظر با استفاده از ميكروفون شور و نرم افزار پرت ضبط شد. سپس مقادير بسامد سازه هاي اول و دوم براي هر واكه اندازه گيري و مقايسه شد. نتايج نشان داد كه كودكان داراي اختلال شنوايي واكه هاي [u, i, e, ᴂ] را در جايگاهي افتاده تر نسبت به كودكان بدون اختلال شنوايي توليد مي كنند. واكه [a] در كودكان كاشت حلزون شنوايي در جايگاهي افتاده تر و واكه [o] در كودكان داراي اختلال شنوايي در جايگاهي افراشته تر نسبت به كودكان بدون اختلال شنوايي توليد مي شود. در حالي كه واكه [a] در كودكان داراي سمعك در جايگاهي افراشته تر نسبت به كودكان بدون اختلال شنوايي توليد مي شود. به علاوه، تمامي واكه هاي كودكان كاشت حلزون شنوايي و واكه هاي ᴂ] [u, i, e, a, در كودكان داراي سمعك در جايگاهي پيشين تر نسبت به كودكان بدون اختلال شنوايي توليد مي شوند. كودكان داراي سمعك داراي كوچك ترين فضاي واكه اي در بين افراد شركت كننده در تحقيق هستند، درحالي كه فضاي واكه اي كودكان كاشت حلزون شنوايي تفاوت فاحشي با فضاي واكه اي كودكان بدون اختلال شنوايي نداشت. جنسيت نيز بر بسامد سازه اول واكه[a] و بسامد سازه دوم واكه [i] تاثيري معنادار داشت.
چكيده لاتين :
We live in a world of language and we communicate with each other using
language (Fromkin et al., 2007). Deafness occurs when a person cannot
understand speech through hearing, even when the sound is amplified. The
degree of hearing loss is measured according to the sensitivity of deaf
people’s ears to the sounds (Ganji, 2017) and then those people are asked to
use hearing aids or do cochlear implantation surgery (Ebrahimi, 2006).
Children have the opportunity to hear others’ speech during normal speech
development while children with hearing impairment lose much of the
auditory input, which may hinder speech development (Tseng et al., 2011 as
cited in Serry and Blamey, 1999; Blamey et al., 2001; Peng et al., 2004;
Bouchard et al., 2007). Different factors will affect speech development.
One of these factors is DISABILITY, any disorder in hearing will affect
speech and subsequently will cause problems in communication (Amiri et
al., 2014). Some speech characteristics of children with hearing loss are
different from each other and different from normally hearing children (Kord
et al., 2012). GENDER is another factor affecting speech. While analyzing
vowels produced by Azari speakers, Mirahadi et al. (2018) proved that men
produce some vowels different from women.
Vowel space is a vowel quadrilateral which is used to shows the first and
the second formants. Phoneticians put vowels in the vowel space according
to their position in the oral cavity, which was first introduced by Essner
(1947) and Joos (1948) (as cited in Harrington & Cassidy, 1999). The first
formant will increase as we go down the vowel space, it shows highness of
tongue while producing vowels in the oral cavity. The second formant shows anterior or posterior position of tongue in the process of production of
vowels in the oral cavity and will increase as we go to the left side of the
vowel space (Hayward, 2013: 227, 228 & 502).
The present study aims to compare the vowel space of hearing aided,
cochlear implanted, and normally hearing children, with DISABILITY and
GENDER as factors, in order to investigate the difference between the
vowels produced by these children (Their average age was 10 years and 4
months and their participation in the study was optional, after getting
permission from their parents.) and find out more effective hearing aid tools
among two groups of children with DISABILITY (They did not have any
mental or physical problems except hearing impairment and took part in
language therapy classes for about 450 hours.), the group which makes
vowels similar to normally hearing children will prove the effectivity of the
hearing aid tools. So, the results will be useful for language therapists while
helping children learn how to pronounce vowels.
Therefore, the participants, 5 girls and 5 boys in each group, were asked
to repeat thirty-six CVC framed words. Each word consists of one of the
stops [p, b, t, d, k, g] in the onset and offset of the pattern and one of the
Persian vowels [æ, e, o, a, i, u] in the center. Then the words were recorded
using a Shure microphone in PRAAT software. After that, the first and the
second formants of each vowel were measured and by using SPSS software
the data was analyzed.
The results showed that the effect of DISABILITY on the first formant of
vowels [æ, a, i, u] and the second formant of vowels [a, e, o, u] was
significantly different (p < 0.050). The results of a Post Hoc Bonferroni test
showed that children with DISABILITY produced vowels [u, i, e, ] in a
lower place in the vowel space comparing to normally hearings. Cochlear
implanted children produced vowel [a] in a lower place and vowel [o] in a
higher place in the vowel space comparing to normally hearings. Hearing
aided children produced vowel [a] in a higher place in the vowel space
comparing to normally hearings. All vowels in cochlear implanted children
and vowels [, a, e, i, u] in hearing aided children were produced in an
anterior place in the vowel space comparing to normally hearings.
The results also proved that the effect of GENDER on the first formant of
vowel [a] and the second formant of vowel [i] was significantly different (p< 0.050). The results of a Post Hoc Bonferroni test revealed that the mean of
the first formant of vowel [a] in girls was more than boys and the mean of
the second formant of vowel [i] in girls was less than boys.
It is also important to mention that hearing aided children had the
smallest vowel space among three groups of participants while the vowel
space of cochlear implanted children was not so different from the vowel
space of normally hearings. So, language therapists have to try more to teach
vowels to the children who use hearing aids comparing to the children who
are cochlear implanted.
