Negative value for Theta and Alpha when (averaged)


#1

I collected EEG data and wanted to work on Theta band power with Af7 and Af8 channels but I am getting negative average value for Theta band corresponding to a certain task. Is there something wrong? There should not be a negative value for power.

Please help me understand the reason behind negative average values for Theta and Alpha bands.

Thanks


#2

the Muse SDK automatically takes the log10() of the power, so anything that was originally less than 1 will give you a negative. Not sure why they do that, I always do 10^power to get it back to the original value before doing anything with it.