Hi all,
Apologies if my query is a little specific or simple, but I've been struggling with this one for a few months. I've run a series of seed-based whole brain connectivity analyses through FEAT, and have turned up some interesting results. I initially ran a first analysis with a precuneus seed, and was able to chart my DMN connectivity (great), and then ran a second analysis with demeaned questionnaire scores as a predictive EV. This led to a significant prefrontal cluster being identified, and I wanted to extract the connectivity values for the purpose of displaying my results on a scatterplot. I used Featquery as suggested on your Wiki using Cope1 from the first analysis, and an extracted mask of my prefrontal cluster.
My question relates to the Featquery output. I've attached a link to an image showing the "Mean time series (masked/weighted)" link that leads to a mean value for each participant being printed out. When transferring these to Excel and plotting them against my EV, they do appear to represent PreCu<-> Prefrontal cluster connectivity values, but I can't get to the bottom of what unit these values are in?
Based on other test analyses I've run to figure this out, the values are always between -99 and 99 (link to screenshot also attached) and I've heard some people suggest that they're adapted Pearson R values, although I personally doubt this? Would it be some form of Z-scored connectivity/activation unit? I'd just be very pleased to know so that I can better understand my results and (more/less) importantly, label the axes accordingly!
Many thanks for any help,
Richard
1) Screenshot of Featquery Mean time series link: https://www.dropbox.com/s/m2dge7wr2e6y1ko/FeatQuery.jpg?dl=0
2) Screenshot of resulting mean time series values for each participant (no unit): https://www.dropbox.com/s/x8yhne178b57jbd/FeatQuery2.jpg?dl=0
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