Instrumental study of laryngeal characteristics of vowel syllable nuclei in Iranian languages. Challenges, advantages, and results

The article deals with the results of an instrumental study of the larynx work in order to determine the correlation between laryngeal (characterizing larynx and vocal folds vibrations) and acoustic (pitch frequency, duration and intensity) properties of vowels and stress in Iranian languages. The methodological basis of the study is experimental and statistical analysis, as well as a comparative approach. The material used was studio recordings of speech in Iranian languages, obtained using a microphone and an electroglottograph. That tool allows non-invasive assessment of the degree of the vocal cords closure during phonation and sound articulation. When recording speech, the acoustic and laryngeal signals are registered separately, which improves the quality of the analyzed materials and separates the speech flow from extraneous noises. Native speakers of Persian (three men and three women), Gilaki (three women) and Wakhi (two men and two women) took part in the study. The vowel parameters were analyzed using the Praat speech analysis program and statistically processed in the IBM SPSS Statistics program. The results showed that in the languages examined, stressed syllables are marked by different means. The stressed vowel in Persian is marked by an increase in pitch and decrease in infrasonic frequency of laryngeal oscillations (laryngeal correlate). In Gilaki duration plays a key role in marking vowel stress, somewhat less regularly – an increase in the frequency of the pitch and intensity, a laryngeal correlate has also been discovered – the amplitude of the vertical displacement of the larynx. Wakhi stress proved to be multicomponent, combining the leading quantitative and tonic components with a dynamic one; in addition, the amplitude of the vertical movement of the larynx (laryngeal correlate) is significantly related to stress.

1. Abolhasanizadeh, V., Bijankhan, М. and Gussenhoven, С. (2012), “The Persian pitch accent and its retention after the focus”, Lingua, vol. 122, no. 13, pp. 1380–1394.

2. Dzakhova, V.T. (2010), “On stress in the Ossetian language”, Vestnik RGGU. Seriya “Filologicheskie nauki. Yazykoznanie”, vol. 52, no. 9/12, pp. 9–26.

3. Dzakhova, V.T. (2014), “Implementation of verbal stress in a phrase (based on the analysis of simple declarative sentences in the Ossetian language)”, Vestnik Kalmytskogo universiteta, vol. 24, no. 4, pp. 31–40.

4. Dodykhudoeva, L.R. (2014), “Pamir languages in the context of language shift”, Yazykovaya politika i yazykovye konflikty v sovremennom mire: Mezhdunarodnaya konferentsiya: Doklady i soobshcheniya [Language policy and language conflicts in the modern world. International Conference: Reports and presentations], Tezaurus, Moscow, Russia, pp. 430–437.

5. Earle, M.A. (1975), An acoustic study of northern Vietnamese tones. Speech Communications Research Laboratory, Santa Barbara, CA, USA.

6. Gryunberg, A.L. and Steblin-Kamenskii, I.M. (1976), Yazyki Vostochnogo Gindukusha: Vakhanskii yazyk: Teksty, slovar’, grammaticheskii ocherk [Languages of the Eastern Hindu Kush. Wakhi. Texts, dictionary, grammar essay], Nauka, Moscow, USSR.

7. Hussain, Q. and Mielke, J. (2018), “Stop laryngeal contrasts of endangered languages of Northern Pakistan”, Journal of the Acoustical Society of America (JASA), vol. 143, no. 3, p. 1754, https://doi.org/10.1121/1.5035740

8. Ivanov, V.B. (1972), “On Persian word stress (Experimental research experience)”, Vestnik Moskovskogo universiteta. Seriya 13: Vostokovedenie, vol. 2, pp. 83–91.

9. Ivanov, V.B. (1988), “Stress in Dari (the analysis stage)”, in Lebedev, K.A. and Ostrovskii, B.Ya., eds., Aktual’nye problemy stroya iranskikh yazykov [Current issues of the structure of Iranian languages], Izdatel’stvo MGU, Moscow, USSR, pp. 27–41.

10. Ivanov, V.B. (1996), Vokalizm i prosodika v persidskom yazyke i dari [Vocalism and prosody in Persian and Dari], Abstract of D. Sc. Dissertation (Philology), Institut yazykoznaniya RAN, Moscow, Russia.

11. Ivanov, V.B. (2001), “Prosodic reduction of vowels in Pashto”, Issledovaniya po iranskoi filologii [Research in Iranian philology], Gumanitarii, Moscow, Russia, iss. 3, pp. 5–17.

12. Ivanov, V.B. (2008), “Quantitative stress in Sarykoli”, in Meier, M.S. and Geveling, L.V., eds., Lomonosovskie chteniya. Vostokovedenie. Nauchnaya konferentsiya: aprel’ 2008 g.: Tezisy dokladov [Lomonosov Scientific Conference. Oriental studies. April 2008. Abstracts of reports], Moscow, Russia, pp. 205–207.

13. Ivanov, V.B. (2009), “Study of stress in Gavruni”, in III Mezhdunarodnaya konferentsiya po polevoi lingvistike: sbornik tezisov i materialov [3rd International Conference on Field Linguistics. Collected abstracts], Moscow, Russia, pp. 76–81.

14. Ivanov, V.B. (2011), “Stress in the language of Abyane village”, in Molchanova, E.K., ed., Leksika. Etimologiya. Yazykovye kontakty. K yubileyu doktora filologicheskikh nauk, professora Dzhoi Iosifovny Edel’man [Vocabulary. Etymology. Language contacts. On the anniversary of Doctor of Philological Sciences, Professor Joy Iosifovna Edelman], Institut yazykoznaniya RAN, Tezaurus, Moscow, Russia, pp. 176–182.

15. Ivanov, V.B. (2012), “Synthesis of prosodic patterns in Dari”, Rechevye tekhnologii, no. 1, pp. 29–45.

16. Ivanov, V.B. (2014), “Mazanderani prosody”, in Abylgaziev, I.I. and Meier, M.S., eds., Lomonosovskie chteniya. Vostokovedenie: Tezisy dokladov nauchnoi konferentsii (Moskva, 14 aprelya 2014 g.) [Lomonosov Scientific Conference. Oriental studies: Abstracts of the Scientific Conference Reports (Moscow, 14 Apr. 2014)], Klyuch-S, Moscow, Russia, pp. 103–105.

17. Ivanov, V.B. (2015), “Gilaki prosody”, in Abylgaziev, I.I. and Meier, M.S., eds., Lomonosovskie chteniya: Vostokovedenie: Tezisy dokladov nauchnoi konferentsii (Moskva, 20 aprelya 2015 g.) [Lomonosov Scientific Conference. Oriental studies: Abstracts of the Scientific Conference reports (Moscow, 20 Apr. 2015)], Izdatel’stvo MGU, Moscow, Russia, pp. 86–87.

18. Ivanov, V.B. (2019), “Vowels in the speech of Wakhis in Pakistan, Tajikistan and China”, in Lomonosovskie chteniya: Vostokovedenie i Afrikanistika: tezisy dokladov nauchnoi konferentsii (Moskva, 15 aprelya 2019 g.) [Lomonosov Scientific Conference. Oriental and African studies: Abstracts of the Scientific Conference reports (Moscow, 15 Apr. 2019)], Klyuch-S, Moscow, Russia, pp. 108–110.

19. Ivanov, V.B. and Dodykhudoeva, L.R. (2010), “Prosody of the Abyānei language”, in The First International Conference on Iran’s Desert Area Dialects, Semnan, 1–2 Dec. 2010, Semnan University Press, Semnan, Iran, pp. 28–29.

20. Ivanov, V.B. and Dodykhudoeva, L.R. (2017), “Syntactic relations of names in the northwestern Iranian languages (based on Mazanderani and Gilaki material)”, Voprosy yazykoznaniya [Topics in the Study of Language], no. 2, pp. 77–95. https://doi.org/10.31857/S0373658X0000971-7

21. Ivanov, V.B. and Silanteva, L.G. (2019), “Acoustic-glottographic analysis of Wakhi stress”, in Mir nauki, kul’tury, obrazovaniya [The world of science, culture and education], vol. 79, no. 6, pp. 525–527. https://doi.org/10.24411/1991-5497-201910224

22. Ivanov, V.B. and Silanteva, L.G. (2020), “Pitch and duration as main factors of Wakhi stress”, European Journal of Natural History, no. 3, pp. 115–119, https://doi.org/10.17513/ejnh.34098

23. Ivanov, V.B. and Silanteva, L.G. (2023), “Research on word stress in Iranian languages by Soviet and Russian scholars”, Russian Journal of Linguistics, vol. 27, no. 2, pp. 392–417, https://doi.org/10.22363/2687-0088-31015

24. Khaskashev, T.N. (1983), Foneticheskaya priroda slovesnogo udareniya v sovremennom tadzhikskom literaturnom yazyke [Phonetic nature of word stress in the modern Tajik literary language], Donish, Dushanbe.

25. Korn, A. (2016), “A partial tree of Central Iranian: A new look at Iranian subphyla”, Indogermanische Forschungen, vol. 121, no. 1, pp. 401–434, https://doi.org/10.1515/if-2016-0021

26. Korn, A. (2019), “Isoglosses and subdivisions of Iranian”, Journal of Historical Linguistics, vol. 9, no. 2, pp. 239–281, https://doi.org/10.1075/jhl.17010.kor

27. Ladd, D.R. (1996), Intonational phonology, Cambridge University Press, Cambridge, UK. (Cambridge Studies in Linguistics; vol. 79)

28. Natel Khanlari, P. (1959), Vazn-e še’r-e fārsi [The metrics of Persian poetry], Тehran, Iran.

29. Pakhalina, T.N. (1975), Vakhanskii yazyk [The Wakhi language], Nauka, Moscow, USSR.

30. Pakhalina, T.N. and Lashkarbekov, B.B. (2000), “The Wakhi language”, in Rastorgueva, V.S., ed., Yazyki mira. Iranskie yazyki. T. 3: Vostochnoiranskie yazyki [Languages of the world. Iranian languages. Vol. 3. Eastern Iranian languages], Indrik, Moscow, Russia, pp. 174–186.

31. Polyakov, K.I. (1988), Persidskaya fonetika. Opyt sistemnogo issledovaniya [Persian phonetics. System research essay], Nauka, Moscow, USSR.

32. Rastorgueva, V.S., Kerimova, A.A., Mamedzade, A.K., Pireiko, L.A. and Edel’man, D.I. (1971), Gilyanskii yazyk [The Gilaki language], Nauka, Moscow, USSR.

33. Rastorgueva, V.S., Kerimova, A.A., Mamedzade, A.K., Pirejko, L.A., Edel’man, D.I. (2012), The Gilaki Language, Acta Universitatis Upsaliensis, Uppsala, Sweden. (Studia Iranica Upsaliensia; vol. 19)

34. Rose, Ph. (1987), “Considerations in the normalization of the fundamental frequency of linguistic tone”, Speech Communication, vol. 6, no. 4, pp. 343–352, https://doi.org/10.1016/0167-6393(87)90009-4

35. Silanteva, L.G. (2022), “Results of acoustic-glottographic study of Persian prosody”, in Lomonosovskie chteniya. Vostokovedenie i Afrikanistika: tezisy dokladov nauchnoi konferentsii (Moskva, 14–22 aprelya 2022 g.) [Lomonosov Scientific Conference. Oriental and African Studies: Abstracts of the Scientific Conference Reports (Moscow, 14–22 Apr. 2022)], ISAA MGU imeni M.V. Lomonosova, Moscow, Russia, pp. 255–258.

36. Silanteva, L.G. (2023), “Glottographic analysis of stress in Persian”, in Lomonosovskie chteniya. Vostokovedenie i afrikanistika: sbornik materialov nauchnoi konferentsii (Moskva, 4–7 aprelya 2023 g.) [Lomonosov Scientific Conference. Oriental and African Studies. Scientific Conference Proceedings (Moscow, 4–7 Apr. 2023], ISAA MGU imeni M.V. Lomonosova, Moscow, Russia, pp. 193–195.

37. Silanteva, L.G. (2024), “Open quotient in the speech of native Persian speakers”, in Lomonosovskie chteniya. Vostokovedenie i afrikanistika: sbornik materialov nauchnoi konferentsii (Moskva, 28 marta – 3 aprelya 2024 g.) [Lomonosov Scientific Conference. Oriental and African Studies. Scientific Conference Proceedings (Moscow, 28 March – 3 Apr. 2024)], ISAA MGU imeni M.V. Lomonosova, Moscow, R Scientific Conference Proceedings ussia, pp. 300–302.

38. Silanteva, L.G. (2025), “Acoustic and laryngeal correlates of word stress in Gilaki”, Philological Sciences Bulletin, vol. 5, no. 2, pp. 145–152, https://doi.org/10.62257/2782-5329-2025-2

39. Silanteva, L.G. (2025), “Laryngeal characteristics of stressed syllable nuclei in Wakhi”, Teoreticheskaya i prikladnaya lingvistika, vol. 11, no. 2, pp. 113–126. http://doi.org/10.22250/24107190-2025-11-2-113

40. Stilo, D. (2001), “Gīlān x. languages”, Encyclopædia Iranica, vol. 10, no. 6, pp. 660–668, available at: https://iranicaonline.org/articles/gilan-x (Accessed 29 June 2025).

41. Zav’yalova, V.I. (1956), “New information on the phonetics of Iranian languages. Gilaki and Mazandarani”, Trudy Instituta yazykoznaniya AN SSSR [Proceedings of the Institute of Linguistics], vol. 6, Moscow, USSR, pp. 92–112.