Olfactory bulb volume changes following olfactory training in normosmic individuals

Area of Science:

• Neuroscience
• Olfactory research
• Neuroimaging

Background:

• Olfactory training (OT) is associated with olfactory function changes and olfactory bulb (OB) structural modifications.
• The neuroplastic potential within the OB following OT requires further investigation.
• This pilot study examines the impact of varying OT durations on OB volume (OBV) and olfactory function in normosmic individuals.

Purpose of the Study:

• To investigate the neuroplastic effects of olfactory training on olfactory bulb volume.
• To compare the effects of standard versus extended olfactory training durations.
• To assess olfactory function changes in relation to olfactory bulb volume modifications.

Main Methods:

• Seventy-seven normosmic individuals participated in a three-month intervention.
• Participants were assigned to standard OT (40 seconds/day), extended OT (4 minutes/day), or a control group.
• Olfactory bulb volume (MRI) and olfactory function (Sniffin' Sticks) were assessed at baseline, post-intervention, and one-year follow-up.

Main Results:

• Both standard and extended OT groups showed significant increases in OBV compared to controls.
• No significant differences in OBV changes were observed between the standard and extended OT methods.
• No significant improvements in olfactory function were detected in the intervention groups.

Conclusions:

• Olfactory training, regardless of duration, leads to rapid and persistent increases in OBV in normosmic individuals.
• Neuroplastic changes in OBV induced by OT can extend beyond the training period.
• Observed increases in OBV did not correlate with improvements in olfactory function.