Shared and private variability in the auditory cortex

Deweese, M. R., Zador, A. M. (September 2004) Shared and private variability in the auditory cortex. J Neurophysiol, 92 (3). pp. 1840-55. ISSN 0022-3077 (Print)

Abstract

The high variability of cortical sensory responses is often assumed to impose a major constraint on efficient computation. In the auditory cortex, however, response variability can be very low. We have used in vivo whole cell patch-clamp methods to study the trial-to-trial variability of the subthreshold fluctuations in membrane potential underlying tone-evoked responses in the auditory cortex of anesthetized rats. Using methods adapted from classical quantal analysis, we partitioned this subthreshold variability into a private component (which includes synaptic, thermal, and other sources local to the recorded cell) and a shared component arising from network interactions. Here we report that this private component is remarkably small, usually about 1-3 mV, as quantified by the variance divided by the mean of the ensemble of tone-evoked response heights. The shared component can be much larger, and shows more heterogeneity across the population, ranging from about 0 to 10 mV. The remarkable fact that, at least 5 synapses from the auditory periphery, this variability remains so small raises the possibility that the intervening neural circuitry is organized so as to prevent private noise from accumulating as neural signals propagate to the cortex.

Item Type: Paper
Uncontrolled Keywords: Acoustic Stimulation methods Action Potentials physiology Animals Auditory Cortex physiology Evoked Potentials, Auditory physiology Membrane Potentials physiology Rats Rats Sprague-Dawley
Subjects: organism description > animal behavior > auditory
Investigative techniques and equipment > patch-clamp recording
Investigative techniques and equipment > recording devices > patch-clamp recording
CSHL Authors:
Communities: CSHL labs > Zador lab
Depositing User: CSHL Librarian
Date: September 2004
Date Deposited: 09 Feb 2012 17:20
Last Modified: 23 Feb 2017 20:37
Related URLs:
URI: https://repository.cshl.edu/id/eprint/22360

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