Related Experiment Video
Updated: Jul 10, 2026

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A Free-breathing fMRI Method to Study Human Olfactory Function
Published on: July 30, 2017
Associations between olfactory dysfunction and structural MRI findings in Parkinson's disease: a systematic review
Yasaman Alikhani1, Amin Zolfaghari2, Farshad Shahkarami3
1School of Medicine, Tehran University of Medical Sciences (TUMS), Tehran, Iran.
Brain Imaging and Behavior
|July 9, 2026
Summary
Olfactory dysfunction in Parkinson's disease (PD) is linked to structural brain changes in olfactory and limbic regions. These Magnetic Resonance Imaging (MRI) findings may offer early biomarkers for PD.
Area of Science:
- Neuroscience
- Neurology
- Radiology
Background:
- Olfactory dysfunction is a common early non-motor symptom in Parkinson's disease (PD).
- Structural Magnetic Resonance Imaging (MRI) studies show inconsistent findings regarding olfactory-related brain regions in PD.
- Clarifying neuroanatomical correlates is crucial for understanding PD progression.
Conclusions:
- Structural MRI changes in specific brain regions are associated with olfactory dysfunction in Parkinson's disease.
- These neuroanatomical correlates, particularly in olfactory and limbic areas, may serve as potential early biomarkers for PD.
- Further standardized, longitudinal studies are necessary to confirm the diagnostic and prognostic value of these MRI findings.
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