TY - JOUR T1 - Sparse recurrent excitatory connectivity in the microcircuit of the adult mouse and human cortex JF - bioRxiv DO - 10.1101/292706 SP - 292706 AU - Stephanie C. Seeman AU - Luke Campagnola AU - Pasha A. Davoudian AU - Alex Hoggarth AU - Travis A. Hage AU - Alice Bosma-Moody AU - Christopher A. Baker AU - Jung Hoon Lee AU - Stefan Mihalas AU - Corinne Teeter AU - Andrew L. Ko AU - Jeffrey G. Ojemann AU - Ryder P. Gwinn AU - Daniel L. Silbergeld AU - Charles Cobbs AU - John Phillips AU - Ed Lein AU - Gabe J. Murphy AU - Christof Koch AU - Hongkui Zeng AU - Tim Jarsky Y1 - 2018/01/01 UR - http://biorxiv.org/content/early/2018/05/08/292706.abstract N2 - Generating a comprehensive description of cortical networks requires a large-scale, systematic approach. To that end, the Allen Institute is engaged in a pipeline project using multipatch electrophysiology, supplemented with 2-photon optogenetics, to characterize connectivity and synaptic signaling between classes of neurons in adult mouse and human cortex. We focus on producing results detailed enough for the generation of computational models and enabling comparison with future studies. Here we report our examination of intralaminar connectivity within each of several classes of excitatory neurons. We find that connections are sparse but present among all excitatory cell types and layers we sampled, with the most sparse connections in layers 5 and 6. Almost all mouse synapses exhibited short-term depression with similar dynamics. Synaptic signaling between a subset of layer 2/3 neurons; however, exhibited facilitation. These results contribute to a body of evidence describing recurrent excitatory connectivity as a conserved feature of cortical microcircuits. ER -