A distinct entorhinal cortex to hippocampal CA1 direct circuit for olfactory associative learning
- 6 March 2017
- journal article
- Published by Springer Science and Business Media LLC in Nature Neuroscience
- Vol. 20 (4), 559-570
- https://doi.org/10.1038/nn.4517
Abstract
Lateral and medial parts of entorhinal cortex (EC) convey nonspatial 'what' and spatial 'where' information, respectively, into hippocampal CA1, via both the indirect EC layer 2→ hippocampal dentate gyrus→CA3→CA1 and the direct EC layer 3→CA1 paths. However, it remains elusive how the direct path transfers distinct information and contributes to hippocampal learning functions. Here we report that lateral EC projection neurons selectively form direct excitatory synapses onto a subpopulation of morphologically complex, calbindin-expressing pyramidal cells (PCs) in the dorsal CA1 (dCA1), while medial EC neurons uniformly innervate all dCA1 PCs. Optogenetically inactivating the distinct lateral EC-dCA1 connections or the postsynaptic dCA1 calbindin-expressing PC activity slows olfactory associative learning. Moreover, optetrode recordings reveal that dCA1 calbindin-expressing PCs develop more selective spiking responses to odor cues during learning. Thus, our results identify a direct lateral EC→dCA1 circuit that is required for olfactory associative learning.Keywords
This publication has 88 references indexed in Scilit:
- Neuron-type-specific signals for reward and punishment in the ventral tegmental areaNature, 2012
- A Cre-Dependent, Anterograde Transsynaptic Viral Tracer for Mapping Output Pathways of Genetically Marked NeuronsNeuron, 2011
- Pattern separation in the hippocampusTrends in Neurosciences, 2011
- Hippocampal “Time Cells” Bridge the Gap in Memory for Discontiguous EventsNeuron, 2011
- Hippocampal CA1 pyramidal cells form functionally distinct sublayersNature Neuroscience, 2011
- Hippocampal pyramidal cells: the reemergence of cortical laminationBrain Structure and Function, 2011
- Spatial Representation along the Proximodistal Axis of CA1Neuron, 2010
- High-performance genetically targetable optical neural silencing by light-driven proton pumpsNature, 2010
- The subcellular organization of neocortical excitatory connectionsNature, 2009
- Microstructure of a spatial map in the entorhinal cortexNature, 2005