Objectives: No study that compares the connectivity of the Anterior Nucleus (AN) and
Mediodorsal Nucleus (MDN) has been reported yet. In the present study, we attempted to investigate
differences in connectivity between the AN and MDN in the human brain, using probabilistic
Diffusion Tensor Tractography (DTT).
Methods: Forty-one healthy subjects were recruited for this present study. For connectivity of the
AN and MDN, a seed region of interest was placed on the AN and MDN according to the known
anatomical location using probabilistic DTT. Connectivity was defined as the incidence of
connection between the AN/MDN and each brain region.
Results: The AN showed high connectivity to the lateral prefrontal cortex (lPFC, 92.7%), ventromedial
prefrontal cortex (vmPFC,91.5%), and orbitofrontal cortex (OFC,67.1%). The MDN
showed high connectivity to the lPFC (86.6%), vmPFC (84.1%), primary motor cortex (M1,
73.2%), premotor cortex (PMC,72.0%), and OFC (53.7%). In comparison to the difference of connectivity,
no difference in the lPFC, vmPFC, and OFC was observed between the AN and MDN.
Conclusion: We found that both the AN and MDN showed high connectivity to the PFC. In addition,
degree of connectivity from the AN and MDN to the PFC was similar.