The neural connectivity of the inferior olivary nucleus in the human brain: A diffusion tensor tractography study

Objectives: Many animal studies have reported on the neural connectivity of the inferior olivary nucleus (ION). However, the neural connectivity of the ION has not been clearly elucidated in the human brain. In this study, the neural connectivity of the ION in the human brain was investigated by diffusion tensor imaging (DTI). Methods: Forty healthy subjects were recruited. DTIs were acquired using a sensitivity-encoding head coil at 1.5T. Connectivity was defined as the incidence of connection between the ION and regions of interest (ROIs) in the brain. Results: In these subjects, the ION showed higher connectivity to the reticular formation (100%), the posterior limb of internal capsule (100%), the red nucleus (93.75%), the cerebral peduncle of midbrain (91.25%), the primary motor cortex (86.25%), the primary somatosensory cortex (85%), the periaqueductal gray mater (81.25%), the globus pallid us (81.25%), the anterior limb of internal capsule (62.5%), the pontine basis (62.5%), and the posterior parietal cortex (60%). Conclusions: The ION shows high connectivity with motor function-related areas, such as, the posterior limb of internal capsule, the red nucleus, the cerebral peduncle of midbrain, the primary motor cortex, and the pontine basis. These results indicate that the ION is closely related to motor function in the human brain. (C) 2012 Elsevier Ireland Ltd. All rights reserved.