[Eeglablist] ICA/PCA removal of components filtered at different HZ

[Gunn, Matthew P]

Hello,

I had a question regarding the "What happens to the < 1 Hz data if ICA is calculated on > 1 Hz data and applied to 0.1 Hz data? (08/17/2018 Updated)" section on the EEGLAB wiki.

Are the following methods the correct way of doing this?

Set up: I have the same file filter at 1hz and 0.1hz. Also, component 1 is full of Eyeblinks.

Method 1:
1) Run an ICA on the 1hz file
2) Extract component 1 and insert into file filtered 0.1hz (This is done by taking every ICA related variable in the EEG (EEG.icaact, EEG.icawinv, EEG.icaweights, etc)  for the 1hz file and copying them into the 0.1 Hz data)
3) Remove component 1 from the 0.1hz data

Method 2:
1) Run an ICA on the 1hz file
2) With the 0.1 Hz file selected go to Edit->Dataset Info->  select "From other dataset" and set all options to the 1hz file.
3) Remove component 1


If one or both of the methods above are correct would you happen to know why I am getting greatly attuned EEG waves, reduced FFT power across all frequencies, and the appearance of large EEG waves induced by the component removal?

Thank you for the wiki and your time.

Matt Gunn