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Updated: Jul 20, 2026

A Tactile Automated Passive-Finger Stimulator (TAPS)
Published on: June 3, 2009
High-probability uniquantal transmission at excitatory synapses in barrel cortex
R Angus Silver1, Joachim Lubke, Bert Sakmann
1Department of Physiology, University College London, Gower Street, London WC1E 6BT, U.K. a.silver@ucl.ac.uk
Abstract:
The number of vesicles released at excitatory synapses and the number of release sites per synaptic connection are key determinants of information processing in the cortex, yet they remain uncertain. Here we show that the number of functional release sites and the number of anatomically identified synaptic contacts are equal at connections between spiny stellate and pyramidal cells in rat barrel cortex. Moreover, our results indicate that the amount of transmitter released per synaptic contact is independent of release probability and the intrinsic release probability is high. These properties suggest that connections between layer 4 and layer 2/3 are tuned for reliable transmission of spatially distributed, timing-based signals.
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