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Correlations Without Synchrony

Brody, Carlos D. (1999) Correlations Without Synchrony. Neural Computation, 11 (7). pp. 1537-1551. ISSN 0899-7667. doi:10.1162/089976699300016133.

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Peaks in spike train correlograms are usually taken as indicative of spike timing synchronization between neurons. Strictly speaking, however, a peak merely indicates that the two spike trains were not independent. Two biologically plausible ways of departing from independence that are capable of generating peaks very similar to spike timing peaks are described here: covariations over trials in response latency and covariations over trials in neuronal excitability. Since peaks due to these interactions can be similar to spike timing peaks, interpreting a correlogram may be a problem with ambiguous solutions. What peak shapes do latency or excitability interactions generate? When are they similar to spike timing peaks? When can they be ruled out from having caused an observed correlogram peak? These are the questions addressed here. The previous article in this issue proposes quantitative methods to tell cases apart when latency or excitability covariations cannot be ruled out.

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Additional Information:© 1999 Massachusetts Institute of Technology. Received October 20, 1997; accepted November 25, 1998. Posted Online March 13, 2006. I am grateful to John Hopfield and members of his group, Sanjoy Mahajan, Sam Roweis, and Erik Winfree, for discussion and critical readings of the manuscript for this article. I also thank John Hopfield for support. I thank George Gerstein, Kyle Kirkland, and Adam Sillito for discussion, and the anonymous reviewers for helpful comments. This work was supported by a Fulbright/CONACYT graduate fellowship and by NSF Cooperative Agreement EEC-9402726. All simulations and analyses were done in Matlab 5 (Mathworks Inc., Natick, MA). The code for all of these, including in particular the code to reproduce each of the figures, can be found at
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Fulbright/CONACYT Graduate FellowshipUNSPECIFIED
NSF Cooperative AgreementEEC-9402726
Issue or Number:7
Record Number:CaltechAUTHORS:20111201-144231336
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:28280
Deposited By: Tony Diaz
Deposited On:12 Jan 2012 00:07
Last Modified:09 Nov 2021 16:55

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