Functional connectivity fMRI of the rodent brain: comparison of functional connectivity networks in rat and mouse

Area of Science:

• Neuroscience
• Medical Imaging
• Comparative Neurology

Background:

• Resting state functional MRI (rsfMRI) is a valuable tool in human neuropathological research.
• Mice are crucial models for neurological diseases, necessitating robust rsfMRI protocols.
• Comparative studies between mice and rats can enhance understanding of species-specific brain function.

Purpose of the Study:

• To implement and validate resting state functional MRI (rsfMRI) in mice using a standardized protocol.
• To compare rsfMRI findings between mice and rats under comparable experimental conditions.
• To identify species-specific differences in resting-state brain networks.

Main Methods:

• Acquisition of rsfMRI data in both mice and rats.
• Application of a consistent protocol for anesthesia, scanning, and data analysis.
• Utilizing Independent Component Analysis (ICA) to identify functional brain networks.

Main Results:

• rsfMRI outcomes differed significantly between mice and rats.
• Mouse rsfMRI data exhibited unique unilateral cortical components, unlike the bilateral networks in rats.
• A higher number of components in ICA was required to delineate cortical regions in mice compared to rats.

Conclusions:

• rsfMRI is feasible in mice and reveals distinct functional brain organization compared to rats.
• Species-specific differences in cortical network topology exist between mice and rats.
• The number of ICA components is a critical parameter influencing the interpretation of rsfMRI data in different species.