High resolution sub-voxel magnetic susceptibility source separation of pigeon head at 14.1T

Motivation: The precise mechanisms through which pigeons detect and utilize the Earth's magnetic field for orientation and navigation remain to be fully explored. The χ-separation, which is capable of disentangling the sub-voxel contributions of paramagnetic and diamagnetic susceptibility, is utilized to provide novel insights into this physiological processes. Goal(s): To investigate the distribution of paramagnetic and diamagnetic susceptibility in the pigeon head using the χ-separation technique. Approach: Ex vivo pigeon head was scanned at 14.1T MRI with 100 μm isotropic resolution. Results: The results demonstrate that the χ-separation technique can provide previously unseen information on the distribution of paramagnetic and diamagnetic susceptibility. Impact: The distribution of paramagnetic and diamagnetic susceptibility disentangled by χ-separation could provide new insights into the understanding of the mechanisms by which pigeons sense and use the Earth's magnetic field for orientation and navigation.