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LvR for low frequency activity

Posted by Blowfish on 12 Aug 2009 at 01:00 GMT

You filtered your data such that only cells with mean firing rates > 5Hz were used. Is LvR a good measure of irregularity for activity between 1Hz and 4Hz?

No competing interests declared.

RE: LvR for low frequency activity

shino replied to Blowfish on 18 Aug 2009 at 06:49 GMT

Yes. LvR may detect the intrinsic firing characteristics even for low firing rate spike trains. In our paper, we limited the range of firing rate > 5Hz for the purpose of standardizing the analysis, but there is in fact no limit for the use of the metric.

The last term of equation (3) was installed exclusively in LvR for compensating firing refractoriness. As the firing rate lowers, this correction becomes weaker, and LvR would indicate a value close to that of Lv. Nevertheless, both metrics may efficiently detect firing irregularity intrinsic and specific to individual neurons (see Figure 5 for reference).

The refractoriness parameter R was determined to be R=5msec in our paper by maximizing metric performance using the F-test statistic. It is in principle possible to adjust this parameter exclusively to a particular data set in the same manner as this. Note, however, that the robust optimization of the parameter R requires a huge amount of data sets, as has been done in our paper. Thus we would like to recommend adopting the fixed parameter R=5msec in analyzing neuronal firing patterns.

In this connection, we present application programs in the website
which helps researchers analyze the firing rate and irregularity. Using these web applications, one may examine whether or not the firing irregularity varies in time and with behavioral context. We are enriching the website by adding more application programs. You may freely use Java applications or download MATLAB codes from the website.

No competing interests declared.