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Updated: May 28, 2026
10:42
A Free-breathing fMRI Method to Study Human Olfactory Function
Published on: July 30, 2017
Is there a correlation between hippocampus and amygdala volume and olfactory function in healthy subjects?
M Smitka1, S Puschmann, D Buschhueter
1Department of Pediatrics, University of Dresden Medical School, Fetscherstrasse 74, 01307 Dresden, Germany.
Neuroimage
|October 5, 2011
Summary
This study found a small correlation between hippocampus volume and smell function in healthy adults. Age-related normative data for hippocampus and amygdala volumes were also established.
Area of Science:
- Neuroscience
- Olfactory System Research
- Neuroimaging
Background:
- The amygdala (AG) and hippocampus (HC) are key components of the olfactory system.
- Understanding their volumes and relation to olfactory function is crucial for diagnosing olfactory disorders.
Purpose of the Study:
- To compare hippocampus and amygdala volumes in relation to olfactory functions (odor threshold, discrimination, identification, memory).
- To establish age-related normative data for hippocampus and amygdala volumes in healthy adults.
- To investigate potential correlations between brain volumes and olfactory performance, controlling for age.
Main Methods:
- 117 healthy volunteers (aged 19-77) underwent olfactory testing (Sniffin' Sticks) and MRI scans.
- Manual tracing was used for volumetric measurements of the right and left hippocampus and amygdala.
- Mini-Mental-State test excluded participants with dementia.
Main Results:
- Average right HC volume was 3.29 cm³, left 3.15 cm³; average right AG volume was 1.60 cm³, left 1.59 cm³.
- Increasing age correlated with decreased HC and AG volumes, more pronounced on the right side.
- A small but significant correlation was found between right HC volume and odor threshold, independent of age.
Conclusions:
- A modest correlation exists between hippocampus volume and olfactory function in healthy individuals.
- The study provides normative volumetric data for HC and AG, valuable for clinical applications.
- Findings are relevant for understanding olfactory impairment in neurodegenerative diseases and other conditions affecting brain structure.
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