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Dear All, I am using SPM TF-rescale (logR option, with a baseline [-300 0]ms) to rescale each frequency bin of my TF. I however noticed that this leads to some events, on some channels, to be perfectly 0 after correction. Looking at the baseline, the scale looks smaller then for another (randomly chosen) event, but it is for sure non-null (see attached: in blue baseline of event leading to 0 trial, in red, baseline of previous trial, on one channel, for one frequency bin). Looking a little deeper, it seems that this is because the log10 is performed on the whole baseline, before averaging, hence leading to a -Inf value for the baseline. However, if the opposite was performed (i.e. averaging across the baseline before taking the log10), the baseline for that channel would have a value of 0.6341 (log10(mean(xbase)) instead of mean(log10(xbase))). Having 'null' trials throws off all univariate tests I perform later on. Worse, the channels with 'null' events have to be discarded from multivariate analysis (in a specific case). Also, I discovered this pitfall completely by coincidence, as I do not review all events at each channel and each frequency bin. There should be a warning and maybe marking those events as bad if that happens. Can I perform the average before log10? How can this be solved? Thanks! Best, Jessica