Optogenetic Dissection of Entorhinal-Hippocampal Functional Connectivity

Abstract

From Grid to Place Grid cells are considered one of the key sources for place-cell signals in the hippocampus. The entorhinal circuit also contains other functional cell types, but it is unclear which project to the place cells of the hippocampus. Zhang et al. (10.1126/science.1232627, see the Perspective by Poucet and Sargolini ) addressed this question using optogenetics and in vivo multi-electrode electrophysiology. Hippocampal cells received input from a broad spectrum of entorhinal neuronal cell types. Grid cells represented the biggest group of spatial inputs, but border cells, head-direction cells, and a large fraction of nonspatial cells also provided inputs. Thus, hippocampal circuits have local mechanisms for processing specific types of functional input from the entorhinal cortex to generate place-specific signals.