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Updated: Aug 29, 2026

Evaluation of Synapse Density in Hippocampal Rodent Brain Slices
Published on: October 6, 2017
Design for a binary synapse
Peter Sterling1, Robert G Smith
1Department of Neuroscience, University of Pennsylvania, Philadelphia, PA 19104, USA.
Abstract:
The mammalian rod transfers a binary signal, the capture of 0 or 1 photon. In this issue of Neuron, Sampath and Rieke show in mouse that the rod's tonic exocytosis in darkness completely saturates a G protein cascade to close nearly all postsynaptic channels. A full-sized photon event supresses exocytosis sufficiently to allow approximately 30 postsynaptic channels to open simultaneously. Thus, the synapse behaves like a digital gate, whose hallmark is reliability and resistance to noise.
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