Sheng-Jia Zhang, Jing Ye, Jonathan J Couey, Menno Witter, Edvard I Moser, May-Britt Moser
The mammalian space circuit is known to contain several functionally specialized cell types, such as place cells in the hippocampus and grid cells, head-direction cells and border cells in the medial entorhinal cortex (MEC). The interaction between the entorhinal and hippocampal spatial representations is poorly understood, however. We have developed an optogenetic strategy to identify functionally defined cell types in the MEC that project directly to the hippocampus. By expressing channelrhodopsin-2 (ChR2) selectively in the hippocampus-projecting subset of entorhinal projection neurons, we were able to use light-evoked discharge as an instrument to determine whether specific entorhinal cell groups--such as grid cells, border cells and head-direction cells--have direct hippocampal projections...
February 5, 2014: Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences