The olfactory bulb reflects structural plasticity within a genetically stable olfactory network

Area of Science:

• Neuroscience
• Genetics
• Brain Imaging

Background:

• The olfactory bulb (OB) is crucial for smell perception and shows environmental plasticity.
• Understanding the genetic basis of OB structure is vital, given its links to neurological disorders.

Purpose of the Study:

• To investigate the heritability of olfactory bulb volume and olfactory network architecture.
• To determine the extent to which OB structure is genetically determined.

Main Methods:

• Utilized a deep learning model for automated OB segmentation in 941 healthy young adults (twin pairs).
• Employed support vector machine classification to assess zygosity based on morphological similarity.
• Analyzed OB volume and associated olfactory network regions (hippocampus, entorhinal cortex, etc.).

Main Results:

• Olfactory bulb volume alone showed limited heritability.
• Integrating OB volume with other olfactory network regions significantly improved genetic influence classification.
• Genetic influences on the olfactory system are distributed across a network.

Conclusions:

• While the olfactory bulb is plastic, its structure is part of a genetically coordinated network.
• Genetic factors influence the broader olfactory network, not just the OB in isolation.