Journal of Otolaryngology and Ophthalmology of Shandong University ›› 2025, Vol. 39 ›› Issue (5): 132-138.doi: 10.6040/j.issn.1673-3770.0.2023.445

• Review • Previous Articles    

Advances in research on olfactory training that improves cognitive function

LI Han1, QIAO Xiaofeng2   

  1. 1. The Fifth Clinical Medical College of Shanxi Medical University, Taiyuan 030000, Shanxi, China2. Department of Otorhinolaryngology & Head and Neck Surgery, Shanxi Provincial People's Hospital Affiliated to Shanxi Medical University, Taiyuan 030000, Shanxi, China
  • Published:2025-09-19

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Abstract: In various neurodegenerative diseases, olfactory dysfunction and cognitive decline is correlated. Olfactory training(OT)aims to induce neuroplasticity through repetitive exposure to various odorants, thereby cultivating neural adaptability to improve or restore olfactory function. Numerous studies have shown the significant effectiveness of OT in ameliorating olfactory impairments. OT has also been reported to induce changes in brain structure and function. The olfactory pathway interacts with brain regions associated with cognitive function, thus affecting cognitive abilities. OT enhances cortical thickness and functional connectivity in multiple brain regions, thereby alleviating cognitive decline. This review systematically addresses the clinical progress of OT in treating olfactory impairments and its impact on cognitive function, thus providing a basis for the clinical treatment of cognitive function disorders.

Key words: Olfactory training, Cognitive function, Magnetic resonance imaging, Gray matter volume, Functional networks, Olfactory impairment

CLC Number: 

  • R765.6+3
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