Directed and acyclic synaptic connectivity in the human layer 2-3 cortical microcircuit

• DOI: 10.1126/science.adg8828
• Publication Date: 2024-04-18T17:59:28Z
• Authors: Yangfan Peng; Antje Bjelde; Pau Vilimelis Ace...; Franz X. Mittermaier; Henrike Planert; Sabine Grosser; Julia Onken; Katharina Faust; Thilo Kalbhenn; Matthias Simon; Helena Radbruch; Pawel Fidzinski; Dietmar Schmitz; Henrik Alle; Martin Holtkamp; Imre Vida; Benjamin F. Grewe; Jörg R. P. Geiger
• Keywords: 1000 Multidisciplinary; Patch-Clamp Techniques; physiology [Pyramidal Cells]; Rodentia; ultrastructure [Pyramidal Cells]; ultrastructure [Nerve Net]; ddc:320; ultrastructure [Synapses]; 570 Life sciences; biology; Animals; Humans; physiology [Nerve Net]; physiology [Temporal Lobe]; physiology [Synapses]; 10194 Institute of Neuroinformatics

The computational capabilities of neuronal networks are fundamentally constrained by their specific connectivity. Previous studies of cortical connectivity have mostly been carried out in rodents; whether the principles established therein also apply to the evolutionarily expanded human cortex is unclear. We studied network properties within the human temporal cortex using samples obtained from brain surgery. We analyzed multineuron patch-clamp recordings in layer 2-3 pyramidal neurons and identified substantial differences compared with rodents. Reciprocity showed random distribution, synaptic strength was independent from connection probability, and connectivity of the supragranular temporal cortex followed a directed and mostly acyclic graph topology. Application of these principles in neuronal models increased dimensionality of network dynamics, suggesting a critical role for cortical computation.