[Eeglablist] ITCs and Frequency

[arno]

Dear Larry,
> I have two questions about EEG Lab
> 1. Why is it that when you switch the minimum values in ITC options 
> for frequency, you (most of the time) end up with different results?  
> Shouldn't it determine the ideal ITC frequency regardless of the 
> interval you set up? (we use 4 to 20Hz then move up from there to 5 to 
> 20Hz, 6 to 20Hz etc. until we find out desired values).
This is because, the number of cycle (3 by default) is set at the lowest 
frequency. If you do not have "true" wavelets, the number of cycle 
increases with frequency (see message from yesterday), so the output 
picture might change slightly.
> 2. What does downsampling do?  I've adjusted it several times and it 
> doesn't seem to have any effect on our data.
Downsampling do not affect much low frequencies. The advantage is that 
the computation is faster.

Best,

Arno