Related Experiment Videos
Reproducibility of odor maps by fMRI in rodents
James R Schafer1, Ikuhiro Kida, Fuqiang Xu
1Department of Neurobiology, Magnetic Resonance Research Center, Yale University, New Haven, CT 06510, USA.
Neuroimage
|April 25, 2006
Summary
Olfactory spatial maps are reproducible within an individual rodent, but vary significantly between subjects. High-field functional MRI (fMRI) confirms this, showing consistent olfactory bulb activity maps within subjects but not between them.
Area of Science:
- Neuroscience
- Sensory Systems
- Olfactory Research
Background:
- Odorant interactions with olfactory receptor neurons create spatial maps in the olfactory bulb.
- Perceptual odor identification relies on specific and reproducible spatial maps.
- Inter-organism variation in olfactory bulb wiring is suggested by genetic and developmental studies.
Purpose of the Study:
- To assess the reproducibility of odor-induced spatial activity maps in the rodent olfactory bulb.
- To evaluate the utility of functional MRI (fMRI) for studying olfactory bulb function.
- To investigate within- and between-subject variability in olfactory bulb responses.
Main Methods:
- Utilized high-field functional MRI (fMRI) at 7.0 T and 9.4 T.
- Recorded repeated olfactory bulb responses within the same subjects.
- Exposed subjects to a range of odorants from multiple chemical classes.
Main Results:
- Demonstrated fMRI reproducibility in the olfactory bulb comparable to other cortical regions.
- Observed high variability in the precise magnitude and topology of olfactory bulb responses between subjects.
- Localized odor responses to similar broad regions of the glomerular sheet across different bulbs.
Conclusions:
- High-field fMRI is a robust tool for olfactory bulb function analysis.
- Equivalent odor perception may result from divergent neural representations.
- Significant inter-subject variability exists in olfactory bulb neural substrates.