QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

This Article Full Text Full Text (PDF) Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via ISI Web of Science (35) Citing Articles via Google Scholar Google Scholar Articles by Müller, J. R. Articles by Lennie, P. Search for Related Content PubMed PubMed Citation Articles by Müller, J. R. Articles by Lennie, P.

 Previous Article  |  Next Article 

The Journal of Neuroscience, September 1, 2001, 21(17):6978-6990

Information Conveyed by Onset Transients in Responses of Striate Cortical Neurons

James R. Müller¹, Andrew B. Metha¹, John Krauskopf², and Peter Lennie¹

¹ Center for Visual Science and Department of Brain and Cognitive Sciences, University of Rochester, Rochester, New York 14627, and ² Center for Neural Science, New York University, New York, New York 10003

Normal eye movements ensure that the visual world is seen episodically, as a series of often stationary images. In this paper we characterize the responses of neurons in striate cortex to stationary grating patterns presented with abrupt onset. These responses are distinctive. In most neurons the onset of a grating gives rise to a transient discharge that decays with a time constant of 100 msec or less. The early stages of response have higher contrast gain and higher response gain than later stages. Moreover, the variability of discharge during the onset transient is disproportionately low. These factors together make the onset transient an information-rich component of response, such that the detectability and discriminability of stationary gratings grows rapidly to an early peak, within 150 msec of the onset of the response in most neurons. The orientation selectivity of neurons estimated from the first 150 msec of discharge to a stationary grating is indistinguishable from the orientation selectivity estimated from longer segments of discharge to moving gratings. Moving gratings are ultimately more detectable than stationary ones, because responses to the former are continuously renewed. The principal characteristics of the response of a neuron to a stationary gratingthe initial high discharge rate, which decays rapidly, and the change of contrast gain with timeare well captured by a model in which each excitatory synaptic event leads to an immediate reduction in synaptic gain, from which recovery is slow.

Key words: visual cortex; striate cortex; detectability (d'); discriminability; variability; reliability; refractoriness; mean-to-variance ratio; contrast gain; gain control; orientation selectivity; synaptic depression

---

Copyright © 2001 Society for Neuroscience  0270-6474/01/21176978-13$05.00/0

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help