How can I extract the amplitudes of standared EEG bands in a 1 channel EEG signal

I want to analyze the changing frequency amplitudes at Pz when people close there eyes to rest for 20min. I think that I need to filter the raw signal into frequency bands and plot the signal magnitude for each band over time. I especially want to track Alpha band, Theta band, Beta and Delta over a 20 min period. I have MATLAB, Signal Processing Toolbox, EEGLAB and several other tool box add-ons.

Answer 1

[Star Strider]

There are several posts that cover this. If you have R2018a or later, use the bandpass fucntion to design your filters. Get both outputs, and store the second one (the actual filter) for later use with the filtfilt function and other signals. If you don’t have bandpass, elliptical bandpass filters are relatively easy to design. There are several posts on that as well.