Anatomical and physiological foundations of cerebello-hippocampal interaction.

Thomas Charles Watson,Patrice Coulon,Laure Rondi-Reig,Aurélie Watilliaux,Pauline Obiang,Arturo Torres-Herraez,Christelle Rochefort

doi:10.7554/elife.41896

Abstract

Multiple lines of evidence suggest that functionally intact cerebello-hippocampal interactions are required for appropriate spatial processing. However, how the cerebellum anatomically and physiologically engages with the hippocampus to sustain such communication remains unknown. Using rabies virus as a retrograde transneuronal tracer in mice, we reveal that the dorsal hippocampus receives input from topographically restricted and disparate regions of the cerebellum. By simultaneously recording local field potential from both the dorsal hippocampus and anatomically connected cerebellar regions, we additionally suggest that the two structures interact, in a behaviorally dynamic manner, through subregion-specific synchronization of neuronal oscillations in the 6-12 Hz frequency range. Together, these results reveal a novel neural network macro-architecture through which we can understand how a brain region classically associated with motor control, the cerebellum, may influence hippocampal neuronal activity and related functions, such as spatial navigation.

Highlights

The cerebellum is classically associated with motor control
No rabies virus (RABV) or cholera toxin b-subunit (CTb) labeling was found in the cerebellum at this time-course ruling out the existence of a direct cerebello-hippocampal DG pathway in mice
Some RABV-infected neurons were observed in the deep cerebellar and vestibular nuclei 48 hr post-hippocampal infection and some labeled cells were found in the cerebellar cortex at 58 hr p.i. (Figure 1A, inset, Figure 1—figure supplement 4) suggesting the existence of single-relay pathways between the cerebellum and hippocampus

Summary

Introduction

The cerebellum is classically associated with motor control. accumulating evidence suggests its functions may extend to cognitive processes including navigation (Petrosini et al, 1998; Burguiere et al, 2005; Rondi-Reig and Burguiere, 2005; Buckner, 2013; Koziol et al, 2014; Stoodley et al, 2017). A recent study has described, at the single cell and blood-oxygen-level-dependent signal level, sustained activation in the dorsal hippocampus during optogenetic enhancement of cerebellar nuclei output in head-fixed mice (Choe et al, 2018). These data point toward the existence of an anatomical projection from the cerebellum to the hippocampus.

Methods

Results

Conclusion