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A Free-breathing fMRI Method to Study Human Olfactory Function
Published on: July 30, 2017
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Effects of chronic peripheral olfactory loss on functional brain networks
K Kollndorfer1, A Jakab2, C A Mueller3
1Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Austria; Department of Pediatric and Adolescent Medicine, Medical University of Vienna, Austria.
Neuroscience
|September 30, 2015
Summary
Chronic smell loss in anosmic patients reorganizes the brain's olfactory network. Despite intact areas, functional connectivity decreases, suggesting widespread brain effects and compensatory mechanisms.
Area of Science:
- Neuroscience
- Sensory processing
- Olfactory system research
Background:
- Sensory loss impacts central processing across systems.
- The olfactory system can activate via sensorimotor acts without odor stimuli.
- Chronic peripheral smell loss effects on the brain are not well understood.
Purpose of the Study:
- Investigate brain changes associated with chronic peripheral smell loss.
- Examine functional connectivity in the olfactory network of anosmic patients.
- Understand the brain's reorganization in response to olfactory deficits.
Main Methods:
- Functional magnetic resonance imaging (fMRI) experiment using a sniffing paradigm.
- Inclusion of 11 anosmic patients and 14 healthy controls.
- Analysis using group-independent component analysis and functional connectivity analysis.
Main Results:
- Anosmic patients exhibit a spatially intact olfactory network.
- Significant aberrations in functional connectivity were observed in anosmic patients.
- Peripheral smell loss leads to decreased functional connectivity in distributed brain areas.
Conclusions:
- Anosmic patients can activate olfaction-related networks via the sensorimotor component of sniffing.
- Brain areas activated are similar to healthy controls, but functional connectivity differs.
- Loss of smell induces widespread brain effects, potentially triggering compensatory mechanisms in other sensory systems.
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