Training your sensitivity to smell through training and repeated exposure to odorants is a captivating area of research. However, the efficacy of intensive olfactory training in healthy individuals and its underlying neurobiological mechanisms remain relatively unexplored. In this study, published in Neuroimage in 2019 they investigated the effects of a 6-week intensive and meticulously controlled olfactory training program on olfactory function and brain structure.
Study Design
- Participants: Thirty-six healthy young individuals were recruited and randomly assigned to three groups:
- Olfactory Training Group: 12 participants underwent daily intensive olfactory training for at least 20 minutes. Their training included:
- (a) Odor Intensity Classification Task
- (b) Odor Quality Classification Task
- © Target Odor Detection Task
- Visual Control Group: 12 participants underwent an equivalent visual training program.
- Control Group: 12 individuals did not participate in any training.
- Assessments: Before and after the 6-week training period, all participants underwent a battery of olfactory tests.
- Neuroimaging: Participants from the olfactory training group and visual control group also underwent structural magnetic resonance (MR) imaging. Cortical thickness and tissue density were measured.
Key Findings
- Improved Olfactory Function:
- Participants in the olfactory training group showed significant improvement in olfactory function across the trained tasks during the 6-week period.
- Notably, their general olfactory function surpassed that of the control participants, particularly in odor identification. This phenomenon demonstrates intramodal transfer, where training in one specific aspect of olfaction positively impacts other related functions.
- Brain Structural Changes:
- MR imaging analysis revealed alterations in brain structure following olfactory training:
- Increased Cortical Thickness:
- The right inferior frontal gyrus exhibited greater cortical thickness.
- Both the bilateral fusiform gyrus and the right entorhinal cortex also showed increased cortical thickness.
- These structural changes suggest neuroplasticity induced by intensive olfactory training.
Implications and Future Directions
- Clinical Applications: Olfactory training could be beneficial for individuals with olfactory impairments, such as anosmia (loss of smell).
- Neuroplasticity: The study highlights the brain’s remarkable ability to adapt and reorganize in response to sensory training.
- Further Research: Investigating the long-term effects of olfactory training and its impact on other cognitive functions remains an exciting avenue for future studies.
In summary, this research underscores the power of intensive olfactory training to enhance our sense of smell and reshape our brain structure. So, the next time you savor a delightful aroma, remember that your brain is also undergoing fascinating changes!
