BOLD percent signal change

Submitted by bharton on
 Dear all,

I would like to plot the time courses for two regions in the DMN -- Posterior cingulate cortex and medial prefrontal cortex -- so I can graphically see if the two regions are positively or negatively correlated over time.  I am running voxel-wise analyses and I am getting the ROI_FC... text file outputs.  I am a little confused about what these values are and if I plotted them, what would the y-axis be labeled and if these are even the true representation of signal changes over time?  Also, I would like anyone's opinion on if this type of graph would even be meaningful?  I would like to show the graph and the zmap overlayed on subjects' T1 volumes.

You're help is much much appreciated!!

Brett

YAN Chao-Gan

Fri, 09/14/2012 - 16:54

Hi!

If you want to "plot the time courses for two regions in the DMN", then you can use REST->Utilities->Extract ROI Signals to extract the time course for PCC and MPFC. The values are the preprocessed BOLS signals, and the y-label is an arbitrary unit. You can see such a graph in Fox et al., 2005, they demonstrated the negative/positive correlation with the graphic time seres.


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