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Updated: Jan 3, 2026
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A Free-breathing fMRI Method to Study Human Olfactory Function
Published on: July 30, 2017
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Olfactory identification associates with cognitive function and the third ventricle width in patients with
Kazumasa Okada1, Shingo Kakeda2, Masayuki Tahara3
1Department of Neurology, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan.
Multiple Sclerosis and Related Disorders
|November 26, 2019
Summary
Olfactory dysfunction, or impaired odor identification, is linked to cognitive decline and brain atrophy in relapsing-remitting multiple sclerosis (RRMS). This suggests smell tests could aid in assessing RRMS progression and diffuse neurodegeneration.
Area of Science:
- Neuroscience
- Neurology
- Clinical Assessment
Background:
- Olfactory dysfunction is a recognized clinical symptom in multiple sclerosis (MS).
- Impaired odor identification correlates with cognitive deficits in MS patients.
- This study examines olfactory identification's role in assessing relapsing-remitting MS (RRMS) disease state, cognitive function, and brain volume.
Purpose of the Study:
- To investigate the relationship between olfactory identification ability and cognitive function in RRMS.
- To assess the association between olfactory identification and central brain volume in RRMS.
- To evaluate the potential of olfactory identification as a clinical marker for RRMS.
Main Methods:
- Forty RRMS patients and 40 healthy controls (HCs) were assessed.
- Olfactory identification was measured using the Odor Stick Identification Test for the Japanese (OSIT-J).
- Cognitive function (processing speed, working memory) and brain atrophy (third ventricle width) were evaluated.
Main Results:
- RRMS patients exhibited significantly lower OSIT-J scores compared to HCs.
- Lower OSIT-J scores correlated with impaired processing speed and working memory in RRMS patients.
- OSIT-J scores were significantly associated with processing speed, working memory, and third ventricle width.
Conclusions:
- Olfactory identification impairment in RRMS is linked to cognitive dysfunction and central brain atrophy.
- Olfactory identification may serve as a valuable disease marker in RRMS, reflecting diffuse neurodegeneration.
- This highlights the potential of smell tests in assessing cognitive impairment, particularly processing speed, in RRMS.
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