A distinct entorhinal cortex to hippocampal CA1 direct circuit for olfactory associative learning

Entorhinal cortex transfers multimodal information to hippocampus CA1 neurons via indirect and direct pathways. The authors show that excitatory projections from lateral entorhinal cortex selectively target a subpopulation of morphologically complex, calbindin-expressing pyramidal cells in CA1, forming a distinct direct circuit that is required for olfactory associative learning.