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Updated: May 1, 2026

Evaluation of Synapse Density in Hippocampal Rodent Brain Slices
Published on: October 6, 2017
Local connectivity and synaptic dynamics in mouse and human neocortex
Luke Campagnola1, Stephanie C Seeman1, Thomas Chartrand1
1Allen Institute for Brain Science, Seattle, WA, USA.
Abstract:
We present a unique, extensive, and open synaptic physiology analysis platform and dataset. Through its application, we reveal principles that relate cell type to synaptic properties and intralaminar circuit organization in the mouse and human cortex. The dynamics of excitatory synapses align with the postsynaptic cell subclass, whereas inhibitory synapse dynamics partly align with presynaptic cell subclass but with considerable overlap. Synaptic properties are heterogeneous in most subclass-to-subclass connections. The two main axes of heterogeneity are strength and variability. Cell subclasses divide along the variability axis, whereas the strength axis accounts for substantial heterogeneity within the subclass. In the human cortex, excitatory-to-excitatory synaptic dynamics are distinct from those in the mouse cortex and vary with depth across layers 2 and 3.
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