Evaluation of the Relationship between Depression and the Volume of Olfactory Regions by Parcellation Method

Cyprus Turkish Journal of Psychiatry & Psychology, Early View

Published Online: 03 July 2026, Doi:10.35365/ctjpp.26.3.01

RESEARCH ARTICLE / ARAŞTIRMA YAZISI

Evaluation of the Relationship between Depression and the Volume of Olfactory Regions by Parcellation Method

Depresyon ve Koku Bölgeleri Hacmi Arasındaki İlişkinin Parselasyon Yöntemiyle Değerlendirilmesi

Merve Yurt¹ , Merve Şahin Can² , Emrah Özcan¹ , Aslıhan Çetinel¹ , Esma Gül³ , Ömür Karaca¹ , İlter Tuş¹

Abstract:

Scientific studies in the literature have demonstrated olfactory loss and reduced olfactory bulb volume in individuals with major depressive disorder. This study aims to evaluate the correlation between major depressive disorder and olfactory region volume. In the study, Magnetic Resonance İmaging (MRI) images of 33 patients with major depressive disorder and 33 healthy controls from Balıkesir University Hospital’s Mental Health Clinic were retrospectively analyzed. In the obtained MRI series, the volumes of the amygdala, fusiform gyrus, anterior commissure, olfactory radiation, and entorhinal area, which are involved in olfaction, were measured using a parcellation method. All data were transferred to SPSS and analyzed quantitatively. The statistical analysis of the variables examined in the study revealed that the right and left amygdalae tend to be smaller in individuals with illness. It was determined that there was a positive correlation among the parameters evaluated in the study: left amygdala, left entorhinal area, right and left fusiform gyrus volumes, and the Hamilton Depression Scale. As a result of the research, it was revealed in the direction of morphometric analysis that there is a negative relationship between major depressive disorder and olfactory regions. The data obtained in light of these findings will contribute to understanding the cause-and-effect relationship between depression and loss of smell; for clinicians, it is expected to serve as a guide in diagnosis and treatment.

Keywords: Major depression, Olfaction, Magnetic resonance imaging, Parcellation.

¹Balıkesir University, Faculty of Medicine, Department of Anatomy, Balıkesir, Türkiye.

²Balıkesir University, Hospital for Health Practice and Research, Department of Psychiatry, Balıkesir, Türkiye.

³Balıkesir University, İvrindi Vocational School of Health Services, Medical Documentation and Secretarial Program, Balıkesir, Türkiye.

Address of Correspondence/Yazışma Adresi: Merve Yurt, Balıkesir University Faculty of Medicine, Morphology Building, Department of Anatomy, Balıkesir University Çağış Campus 10145, Altıeylül/Balıkesir, Türkiye, E-mail: [email protected].

Date of Received/Geliş Tarihi: 29.07.2025, Date of Revision/Düzeltme Tarihi: 30.11.2025, Date of Acceptance/Kabul Tarihi:03.12.2025, Date of Online Publication/Çevirimiçi Yayın Tarihi: 03.07.2026

Citing/Referans Gösterimi: Yurt, M., Can, M. Ş., Özcan, E., Çetinel, A., Gül, E., Karaca, Ö., & Kuş, İ. (2026). Evaluation of the relationship between depression and the volume of olfactory regions by parcellation method, Cyprus Turkish Journal of Psychiatry & Psychology, 1-8, Doi:10.35365/ctjpp.26.3.01

© 2026 The Author(s). Published by Cyprus Mental Health Institute / Cyprus Turkish Journal of Psychiatry and Psychology (www.ktppdergisi.com). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 license which permits use, sharing, adaptation, distribution and reproduction in any medium or format, provided the original work is properly cited and is not used for commercial purposes. https://creativecommons.org/licenses/by-nc-sa/4.0/