[Eeglablist] Time-frequency analysis (subtraction first or analysis first)

[Hsu, Shen-Mou]

Many thanks for lots of help.

With respect to Stan's last comment, I was just back from the CNS meeting and indeed, there was poster discussing how induced gamma oscillation can be attributed to microsaccades based on single trial analysis. The results will be published in Neuron in a short time.

Shen-Mou Hsu


________________________________________
From: eeglablist-bounces at sccn.ucsd.edu [eeglablist-bounces at sccn.ucsd.edu] On Behalf Of Stanley Klein [dualitystan at gmail.com]
Sent: Tuesday, April 15, 2008 4:41 PM
To: eeglablist at sccn.ucsd.edu
Subject: Re: [Eeglablist] Time-frequency analysis (subtraction first or analysis first)

It looks like there is some consensus on whether to subtract first and then the TF or vice versa. That's nice. [On the other hand subtracting first is a nice way to get rid of ERP, but there are better ways, as described next.]

Andrei, I'm not sure I understood your last comment or question, but I have a related question. Whenever one does time-frequency power plots I would think that one should ALWAYS first get the time locked average and subtract it off  of all the individual trials. Then one could do a TF plot of each. How many on this list do that?  I suspect that people mix together the standard evoked response and also the phase varying response. Why do that since its so easy to show the the two TF plots separately.

Also I've heard rumors that saccades and microsaccades are responsible for most EEG gamma oscillations. So one should also put those events into a separate category too. Too bad things are complicated. But it makes life interesting.
Stan