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The contribution of single synapses to sensory representation in vivo.

ABSTRACT: The extent to which synaptic activity can signal a sensory stimulus limits the information available to a neuron. We determined the contribution of individual synapses to sensory representation by recording excitatory postsynaptic currents (EPSCs) in cerebellar granule cells during a time-varying, quantifiable vestibular stimulus. Vestibular-sensitive synapses faithfully reported direction and velocity, rather than position or acceleration of whole-body motion, via bidirectional modulation of EPSC frequency. The lack of short-term synaptic dynamics ensured a highly linear relationship between velocity and charge transfer, and as few as 100 synapses provided resolution approaching psychophysical limits. This indicates that highly accurate stimulus representation can be achieved by small networks and even within single neurons.

SUBMITTER: Arenz A

PROVIDER: S-EPMC2771362 | biostudies-literature | 2008 Aug

REPOSITORIES: biostudies-literature

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The contribution of single synapses to sensory representation in vivo.

Arenz Alexander A Silver R Angus RA Schaefer Andreas T AT Margrie Troy W TW

Science (New York, N.Y.) 20080801 5891

The extent to which synaptic activity can signal a sensory stimulus limits the information available to a neuron. We determined the contribution of individual synapses to sensory representation by recording excitatory postsynaptic currents (EPSCs) in cerebellar granule cells during a time-varying, quantifiable vestibular stimulus. Vestibular-sensitive synapses faithfully reported direction and velocity, rather than position or acceleration of whole-body motion, via bidirectional modulation of EP ...[more]

PMID: 18703744

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