Intrinsic Hippocampal-Caudate Interaction Correlates with Human Navigation

It has been indicated that both egocentric and allocentric representation systems exist in parallel, and combine to support spatial navigation according to the task. Identifying the neuronal mechanisms and functional roles of the interactions between the two systems promises to provide new insights into the organization of human navigation network. Here we combined resting-state fMRI and behavioral tasks to investigate how the core structures of these systems (i.e., hippocampus and caudate) functionally interact, and further examined their behavioral relevance in navigation in healthy young adults (N = 190). We found a slightly positive connectivity between the hippocampus and caudate (especially in good navigators), suggesting an effective hippocampal-caudate cross talk, which may facilitate the functional integration of the two systems. Interestingly, the hippocampal-caudate interaction correlated with better self-reported navigation ability. Moreover, using an extra 3D pointing task in virtual reality, we found that individuals behavioral performance could be largely predicted by the hippocampal-caudate interactions. Overall, our study demonstrated the intrinsic interaction between two representation systems of the navigation network and its functional roles in behaviors, and further study on dynamic interaction would help us understand better their role in normal aging and psychiatric disorders.