Olfactory training in 8-year-olds increases odour identification ability: a preliminary study

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Abstract

Olfactory training (OT), smelling odours, twice per day for an extended period, can improve the olfactory function in adults. The aim of the current study was to investigate whether OT can improve the olfactory function of children aged 8 years old. Odour thresholds and odour identification ability were compared between two groups across three separate testing sessions (baseline, 6-week post-baseline, 12-week post-baseline). After the baseline test, the control group (n = 21) completed 6 weeks of bi-daily OT with odourless stimuli, whereas the experiment group (n = 20) completed 6 weeks of bi-daily OT, smelling four different odours (eucalyptus, lemon, clove, rose). A repeated measure analysis of variance was used to test for group differences across the three testing sessions. Six weeks after OT had been completed, participants in the experiment group demonstrated a significant increase in odour identification scores (9.95 to 11.20), compared to the control group who demonstrated no increase (10.48 to 10.48). No group differences in odour threshold ability were found.

Conclusion: Six weeks of OT enhances odour identification ability, but not odour thresholds, in 8-year-old children.

What is Known:
• Smell loss and dysfunction are associated with negative health outcomes such as depression and increased risk of consuming contaminated food.
• Olfactory training can improve sense of smell in adults.
What is New:
• Olfactory training improves odour identification ability in 8-year-olds.
• Olfactory training does not appear to enhance odour acuity in 8-year-olds.

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Fig. 1

Data availability

The data is not available due to confidentiality reasons.

Change history

  • 23 February 2021

    Anna Oleszkiewicz's orcid has been updated.

Abbreviations

OT:

Olfactory training

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Acknowledgements

We would like to thank Professor Thomas Hummel for their guidance on this study and feedback on this manuscript.

Funding

This work was supported by the Polish Ministry of Science and Higher Education scholarship for years 2018–2020 (#626/STYP/12/2017) and the National Science Center Poland OPUS grant (2020/37/B/HS6/00288) to AO.

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Authors

Contributions

Mehmet K. Mahmut was responsible for the data analyses, drafting of the initial manuscript and revision of the manuscript. Michał Pieniak, Katarzyna Resler, Valentin A. Schriever and Antje Haehner were responsible for the conceptualization, design and investigation of the study, and reviewing the manuscript. Anna Oleszkiewicz was responsible for the conceptualization, design and investigation of the study, securing research funding, reviewing the manuscript and supervision of the project.

Corresponding author

Correspondence to Mehmet Kibris Mahmut.

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Ethics approval and consent to participate

This study was performed in line with the principles of the Declaration of Helsinki. Ethics approval was received from Wroclaw University’s ethics committee. All participants gave consent prior to beginning the study.

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The authors declare no competing interests.

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Mahmut, M.K., Pieniak, M., Resler, K. et al. Olfactory training in 8-year-olds increases odour identification ability: a preliminary study. Eur J Pediatr (2021). https://doi.org/10.1007/s00431-021-03970-y

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Keywords

  • Olfactory training
  • Children
  • Smell
  • Odour recognition
  • Olfactory function