help > Wavelet analysis issue in Homer2 toolbox
Feb 28, 2018  03:02 PM | Geoff Green - The Ohio State University
Wavelet analysis issue in Homer2 toolbox
I have a question about the wavelet analysis in Homer2, wanted to know how much experience you have had with it and if you'd be able to help with this issue. I have acquainted myself with the software in hope to apply wavelet analysis to the preprocessing stream instead of bandpass filtering.
Currently, I have been able to convert nirx data to .nirs files (homer2 compatible) in order to apply specific preprocessing functions to the time series for specific channels. There are 2 different wavelet corrections, motion correct wavelet and motion correct kurtosis, of which I am trying ti use as a substitute for a bandpass filter. I applied the kurtosis to the time series, but this affected the data in a strange way (image attached "conc_kurtwave") compared to what the data looked like before the kurtosis wavelet (image attached "conc"). Is the kurtosis suppose to have this strange oscillatory type of effect? I have read a little about it, and it seems to be an advancement on the regular wavelet analysis, regular motion correct wavelet sets one threshold value for the wavelet coefficient rejection (Molavi et. al, 2012), while the motion correct kurtosis wavelet has a threshold that varies as a function of the frequency of artifacts in the data; it is iterative (Chiarelli et. al, 2015).

I want to be able to compare this to the regular motion correct wavelet to see which renders a better hrf in the data, however, I get this error message (image attached) when i try to use the regular motion correct wavelet. I see no error in the script it is referring to. I just wanted to know if you had to go through this, or if you know of/can suggest any possible resolutions.
If there is anything that needs clarification, just let me know.
Best,
Geoff D. Green II