The Relationship between Phonological Working Memory and Mean Length of Utterance in Normal and Hearing-Impaired Persian-Speaking Children
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Abstract
Background & Aim: Hearing impairment in childrn can affect language acquisition and consequently lead to delays in speech and language skills. The purpose of this study was to examine the relationship between phonological working memory (PWM) and mean length of utterance (MLU) in normal and hearing-impaired Persian-speaking children.
Methods: The study included 27 children with profound hearing loss (mean age = 5.42 ± 0.31 years) and 27 typically developing children (mean age = 5.62 ± 0.36 years), matched for age range (5–6 years) and gender (12 boys, 15girls). A nonword repetition task was used to assess PWM, and 50 utterances were selected from the obtained discourse samples to evaluate MLU.
Results: The relationship between these two variables was compared across the two groups. A strong and significant correlation was found between PWM and MLU in children with profound hearing loss (HL). Additionally, the correlation in typically developing children was moderate and significant.
Conclusion: A strong correlation between PWM and MLU was found in children with HL, whereas a moderate correlation was observed in typically developing children. These findings indicate the relevance of PWM to MLU in both groups, with a stronger association in children with hearing loss, without implying causality.
1. Vos B, Noll D, Pigeon M, Bagatto M, Fitzpatrick EM. Risk factors for hearing loss in children: a systematic literature review and meta-analysis protocol. Syst Rev. 2019;8(1):172. [DOI:10.1186/s13643-019-1073-x]
2. Edmond K, Chadha S, Hunnicutt C, Strobel N, Manchaiah V, Yoshinga-Itano C; et al. Effectiveness of universal newborn hearing screening: A systematic review and meta-analysis. J Glob Health. 2022;12:12006. [DOI:10.7189/jogh.12.12006]
3. Maria J, Baskar KD, Krishnan A. Macrostructural and microstructural discourse abilities in children with hearing impairment. J Child Lang Acquis Dev. 2021:9(1):176-88.
4. Willis S, Goldbart J, Stansfield J. The strengths and weaknesses in verbal short-term memory and visual working memory in children with hearing impairment and additional language learning difficulties. Int J Pediatr Otorhinolaryngol. 2014;78(7):1107-14. [DOI:10.1016/j.ijporl.2014.04.025]
5. Javanbakht M, Moosavi MB, Vahedi M. The importance of working memory capacity for improving speech in noise comprehension in children with hearing aid. Int J Pediatr Otorhinolaryngol. 2021;147:110774. [DOI:10.1016/j.ijporl.2021.110774]
6. Dumanlar P, Akmese PP, Kirazli G, Kirazli T. An Evaluation of Language Development and Working Memory in Children with Hearing Loss. J Am Acad Audiol. 2024;35(5-06):105-14. [DOI:10.1055/s-0044-1790279]
7. Veraksa A, Bukhalenkova D, Kartushina N, Oshchepkova E. The Relationship between Executive Functions and Language Production in 5-6-Year-Old Children: Insights from Working Memory and Storytelling. Behav Sci (Basel). 2020;10(2):52. [DOI:10.3390/bs10020052]
8. İkiz M, Yücel E. The relationships between language, working memory and rapid naming in children with mild to moderate hearing loss. Int J Pediatr Otorhinolaryngol. 2022;158:111156. [DOI:10.1016/j.ijporl.2022.111156]
9. Lo M, Chen PH. Working Memory Capacity as a Factor Influencing the Relationship between Language Outcome and Rehabilitation in Mandarin-Speaking Preschoolers with Congenital Hearing Impairment. Front Psychol. 2017;8:357. [DOI:10.3389/fpsyg.2017.00357]
10. Bouffier M, Remouchamps R, Majerus S. What is the level of precision of phonological representations in working memory? Mem Cognit. 2025. [DOI:10.3758/s13421-025-01768-z]
11. Stiles DJ, McGregor KK, Bentler RA. Vocabulary and working memory in children fit with hearing aids. J Speech Lang Hear Res. 2012;55(1):154-67. [DOI:10.1044/1092-4388(2011/11-0021)]
12. Soleymani Z, Amidfar M, Dadgar H, Jalaie S. Working memory in Farsi-speaking children with normal development and cochlear implant. Int J Pediatr Otorhinolaryngol. 2014;78(4):674-8. [DOI:10.1016/j.ijporl.2014.01.035]
13. Baddeley A, Gathercole S, Papagno C. The phonological loop as a language learning device. Psychol Rev. 1998;105(1):158-73. [DOI:10.1037/0033-295x.105.1.158]
14. Gathercole SE, Baddeley AD. Evaluation of the role of phonological STM in the development of vocabulary in children: A longitudinal study. J Mem Lang. 1989;28(2):200-13.
15. Nóro LA, Mota HB. Relationship between mean length of utterance and vocabulary in children with typical language development. Rev. CEFAC. 2019;21(6). [DOI:10.1590/1982-0216/20192164419]
16. Ghaderniya N, Alizadeh M, Jalilevand N, Jalaei S, Molla Aghajani S. [Language Sample Length Effect on Mean Length of Utterance in Morpheme in Normal Persian Children]. JPSR. 2019;8(1):17-25. Persian. [DOI:10.22038/JPSR.2019.32819.1814]
17. Murray AD, Fees BS, Crowe LK, Murphy ME, Henriksen AL. The Language Environment of Toddlers in Center-based Care versus Home Settings. Early Childhood Educ J. 2006;34:233-9.[DOI:10.1007/s10643-006-0138-3]
18. Ahadi H, Rezaee H, Nilipour R, Jarollahi F. [The Relationship between Mean Length of utterance (MLU), Lexical Richness and syntactical and lexical metalinguistic Awareness in Bilingual (Azari-Persian) normal and hearing impaired Children]. Journal of Exceptional Children. 2019;19(4):105-18. Persian.
19. Koehlinger KM, Van Horne AJ, Moeller MP. Grammatical outcomes of 3- and 6-year-old children who are hard of hearing. J Speech Lang Hear Res. 2013;56(5):1701-14. [DOI:10.1044/1092-4388(2013/12-0188)]
20. Waring R, Rickard Liow S, Eadie P, Dodd B. Speech development in preschool children: evaluating the contribution of phonological short-term and phonological working memory. J Child Lang. 2019;46(4):632-52. [DOI:10.1017/S0305000919000035]
21. Jafari Z, Ashayeri H, Malayeri S, Ala Aldini F. [Translation, Reliability and Validity of the Newsha Hearing, Language and Speech Development Scale Among Children in Iran]. Payesh. 2009;8(3):271-8. Persian.
22. Jafari Z, Ashayeri H, Malayeri S, Alaedini F. [Validity and Reliability of Newsha Cognitive, Social Communication and Motor Development Scale in Persian Speaking Children]. Psychology Clinical and Psychiatry of Journal Iranian. 2009;15(1):18-24. Persian.
23. Afshar MR, Ghorbani A, Jalilevand N, Kamali M. [Providing the Non-Word Repetition test and determining its validity and reliability and comparing phonological working memory in 4 to 6 Farsi-speaking normal and SSD children in Tehran City]. J Res Rehabil Sci. 2013;9(5):899-911. Persian. [DOI:10.22122/JRRS.V9I5.1161]
24. Afshar MR, Ghorbani A, Rashedi V, Jalilevand N, Kamali M. Working memory span in Persian-speaking children with speech sound disorders and normal speech development. Int J Pediatr Otorhinolaryngol. 2017;101:117-22. [DOI:10.1016/j.ijporl.2017.07.034]
25. Duncan LG. Language and Reading: the Role of Morpheme and Phoneme Awareness. Curr Dev Disord Rep. 2018;5(4):226-34. [DOI:10.1007/s40474-018-0153-2]
26. Jalilevand N. Introducing the Speech and Language Characteristics Checklist for Persian-Speaking Children a Tool for Analyzing Speech Samples. Tehran: Setayesh Hasti; 2023. https://elmnet.ir/doc/32182149-25421?elm_num=17
27. Jalilevand N, Ebrahimipur M, Purqarib J. [Mean length of utterance and grammatical morphemes in speech of two Farsi-speaking children]. Audiol. 2012;21(2):96-108. Persian.
28. Ratner B. The correlation coefficient: Its values range between +1/−1, or do they?. J Target Meas Anal Mark 2099;17:139-42. [DOI:10.1057/jt.2009.5]
29. Richardson JTE. Eta squared and partial eta squared as measures of effect size in educational research. Educ Res Rev. 2011;6(2):135-47. [DOI:10.1016/j.edurev.2010.12.001]
30. Delcenserie A, Genesee F, Trudeau N, Champoux F. The development of phonological memory and language: A multiple groups approach. J Child Lang. 2021;48(2):285-324. [DOI:10.1017/S0305000920000343]
31. Tavakoli M, Jalilevand N, Kamali M, Modarresi Y, Zarandy MM. Language sampling for children with and without cochlear implant: MLU, NDW, and NTW. Int J Pediatr Otorhinolaryngol. 2015;79(12):2191-5. [DOI:10.1016/j.ijporl.2015.10.001]
32. Salmani M, Seyed S, Moradi S, Shirkavand Z, Sadati S, Tabatabaei MS. Production of Persian Morphosyntactic Structures Based on P-LARSP: Comparing Children With/Without Hearing Loss. Archives of Rehabilitation. 2022;22(4):482-505. [DOI:10.32598/RJ.22.4.3307.1]
33. Tuz D, Akti B, Akmeşe PP. Oral Presentations: I Studies: (ID-6878) Evaluation of narrative skills of children with hearing loss. J Hear Sci. 2025;15(1):60.
34. American Speech-Language-Hearing Association. Effects of Hearing Loss on Development. 2025. [Available from: https://www.asha.org/public/hearing/effects-of-hearing-loss-on-development/.
2. Edmond K, Chadha S, Hunnicutt C, Strobel N, Manchaiah V, Yoshinga-Itano C; et al. Effectiveness of universal newborn hearing screening: A systematic review and meta-analysis. J Glob Health. 2022;12:12006. [DOI:10.7189/jogh.12.12006]
3. Maria J, Baskar KD, Krishnan A. Macrostructural and microstructural discourse abilities in children with hearing impairment. J Child Lang Acquis Dev. 2021:9(1):176-88.
4. Willis S, Goldbart J, Stansfield J. The strengths and weaknesses in verbal short-term memory and visual working memory in children with hearing impairment and additional language learning difficulties. Int J Pediatr Otorhinolaryngol. 2014;78(7):1107-14. [DOI:10.1016/j.ijporl.2014.04.025]
5. Javanbakht M, Moosavi MB, Vahedi M. The importance of working memory capacity for improving speech in noise comprehension in children with hearing aid. Int J Pediatr Otorhinolaryngol. 2021;147:110774. [DOI:10.1016/j.ijporl.2021.110774]
6. Dumanlar P, Akmese PP, Kirazli G, Kirazli T. An Evaluation of Language Development and Working Memory in Children with Hearing Loss. J Am Acad Audiol. 2024;35(5-06):105-14. [DOI:10.1055/s-0044-1790279]
7. Veraksa A, Bukhalenkova D, Kartushina N, Oshchepkova E. The Relationship between Executive Functions and Language Production in 5-6-Year-Old Children: Insights from Working Memory and Storytelling. Behav Sci (Basel). 2020;10(2):52. [DOI:10.3390/bs10020052]
8. İkiz M, Yücel E. The relationships between language, working memory and rapid naming in children with mild to moderate hearing loss. Int J Pediatr Otorhinolaryngol. 2022;158:111156. [DOI:10.1016/j.ijporl.2022.111156]
9. Lo M, Chen PH. Working Memory Capacity as a Factor Influencing the Relationship between Language Outcome and Rehabilitation in Mandarin-Speaking Preschoolers with Congenital Hearing Impairment. Front Psychol. 2017;8:357. [DOI:10.3389/fpsyg.2017.00357]
10. Bouffier M, Remouchamps R, Majerus S. What is the level of precision of phonological representations in working memory? Mem Cognit. 2025. [DOI:10.3758/s13421-025-01768-z]
11. Stiles DJ, McGregor KK, Bentler RA. Vocabulary and working memory in children fit with hearing aids. J Speech Lang Hear Res. 2012;55(1):154-67. [DOI:10.1044/1092-4388(2011/11-0021)]
12. Soleymani Z, Amidfar M, Dadgar H, Jalaie S. Working memory in Farsi-speaking children with normal development and cochlear implant. Int J Pediatr Otorhinolaryngol. 2014;78(4):674-8. [DOI:10.1016/j.ijporl.2014.01.035]
13. Baddeley A, Gathercole S, Papagno C. The phonological loop as a language learning device. Psychol Rev. 1998;105(1):158-73. [DOI:10.1037/0033-295x.105.1.158]
14. Gathercole SE, Baddeley AD. Evaluation of the role of phonological STM in the development of vocabulary in children: A longitudinal study. J Mem Lang. 1989;28(2):200-13.
15. Nóro LA, Mota HB. Relationship between mean length of utterance and vocabulary in children with typical language development. Rev. CEFAC. 2019;21(6). [DOI:10.1590/1982-0216/20192164419]
16. Ghaderniya N, Alizadeh M, Jalilevand N, Jalaei S, Molla Aghajani S. [Language Sample Length Effect on Mean Length of Utterance in Morpheme in Normal Persian Children]. JPSR. 2019;8(1):17-25. Persian. [DOI:10.22038/JPSR.2019.32819.1814]
17. Murray AD, Fees BS, Crowe LK, Murphy ME, Henriksen AL. The Language Environment of Toddlers in Center-based Care versus Home Settings. Early Childhood Educ J. 2006;34:233-9.[DOI:10.1007/s10643-006-0138-3]
18. Ahadi H, Rezaee H, Nilipour R, Jarollahi F. [The Relationship between Mean Length of utterance (MLU), Lexical Richness and syntactical and lexical metalinguistic Awareness in Bilingual (Azari-Persian) normal and hearing impaired Children]. Journal of Exceptional Children. 2019;19(4):105-18. Persian.
19. Koehlinger KM, Van Horne AJ, Moeller MP. Grammatical outcomes of 3- and 6-year-old children who are hard of hearing. J Speech Lang Hear Res. 2013;56(5):1701-14. [DOI:10.1044/1092-4388(2013/12-0188)]
20. Waring R, Rickard Liow S, Eadie P, Dodd B. Speech development in preschool children: evaluating the contribution of phonological short-term and phonological working memory. J Child Lang. 2019;46(4):632-52. [DOI:10.1017/S0305000919000035]
21. Jafari Z, Ashayeri H, Malayeri S, Ala Aldini F. [Translation, Reliability and Validity of the Newsha Hearing, Language and Speech Development Scale Among Children in Iran]. Payesh. 2009;8(3):271-8. Persian.
22. Jafari Z, Ashayeri H, Malayeri S, Alaedini F. [Validity and Reliability of Newsha Cognitive, Social Communication and Motor Development Scale in Persian Speaking Children]. Psychology Clinical and Psychiatry of Journal Iranian. 2009;15(1):18-24. Persian.
23. Afshar MR, Ghorbani A, Jalilevand N, Kamali M. [Providing the Non-Word Repetition test and determining its validity and reliability and comparing phonological working memory in 4 to 6 Farsi-speaking normal and SSD children in Tehran City]. J Res Rehabil Sci. 2013;9(5):899-911. Persian. [DOI:10.22122/JRRS.V9I5.1161]
24. Afshar MR, Ghorbani A, Rashedi V, Jalilevand N, Kamali M. Working memory span in Persian-speaking children with speech sound disorders and normal speech development. Int J Pediatr Otorhinolaryngol. 2017;101:117-22. [DOI:10.1016/j.ijporl.2017.07.034]
25. Duncan LG. Language and Reading: the Role of Morpheme and Phoneme Awareness. Curr Dev Disord Rep. 2018;5(4):226-34. [DOI:10.1007/s40474-018-0153-2]
26. Jalilevand N. Introducing the Speech and Language Characteristics Checklist for Persian-Speaking Children a Tool for Analyzing Speech Samples. Tehran: Setayesh Hasti; 2023. https://elmnet.ir/doc/32182149-25421?elm_num=17
27. Jalilevand N, Ebrahimipur M, Purqarib J. [Mean length of utterance and grammatical morphemes in speech of two Farsi-speaking children]. Audiol. 2012;21(2):96-108. Persian.
28. Ratner B. The correlation coefficient: Its values range between +1/−1, or do they?. J Target Meas Anal Mark 2099;17:139-42. [DOI:10.1057/jt.2009.5]
29. Richardson JTE. Eta squared and partial eta squared as measures of effect size in educational research. Educ Res Rev. 2011;6(2):135-47. [DOI:10.1016/j.edurev.2010.12.001]
30. Delcenserie A, Genesee F, Trudeau N, Champoux F. The development of phonological memory and language: A multiple groups approach. J Child Lang. 2021;48(2):285-324. [DOI:10.1017/S0305000920000343]
31. Tavakoli M, Jalilevand N, Kamali M, Modarresi Y, Zarandy MM. Language sampling for children with and without cochlear implant: MLU, NDW, and NTW. Int J Pediatr Otorhinolaryngol. 2015;79(12):2191-5. [DOI:10.1016/j.ijporl.2015.10.001]
32. Salmani M, Seyed S, Moradi S, Shirkavand Z, Sadati S, Tabatabaei MS. Production of Persian Morphosyntactic Structures Based on P-LARSP: Comparing Children With/Without Hearing Loss. Archives of Rehabilitation. 2022;22(4):482-505. [DOI:10.32598/RJ.22.4.3307.1]
33. Tuz D, Akti B, Akmeşe PP. Oral Presentations: I Studies: (ID-6878) Evaluation of narrative skills of children with hearing loss. J Hear Sci. 2025;15(1):60.
34. American Speech-Language-Hearing Association. Effects of Hearing Loss on Development. 2025. [Available from: https://www.asha.org/public/hearing/effects-of-hearing-loss-on-development/.
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How to Cite
1.
Cheraghi M, Baghban K, Rezaei B, Farhadian M, Zarei S. The Relationship between Phonological Working Memory and Mean Length of Utterance in Normal and Hearing-Impaired Persian-Speaking Children. Aud Vestib Res. 2026;.
