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Dear FreeSurfer team,
I'm using fsfast to analyze 1.2mm^3 7T BOLD data collected with a partial coverage over the hippocampus and superior temporal lobe.
I ran preprocessing with the following flags: preproc-sess -d /functional-data -s SUB01 -fsd bold -surface SUB01 lhrh -fwhm 2 -init-header -bbr-int /functional-data/SUB04/bold mT2_WB -per-session
And then I ran the GLM analysis (stimulus-vs-baseline) using selxavg3-sess, keeping the data in the subject's native space (using the '-native' flag combined with '-per-session').
The resulting t-map shows a diagonal line of spurious activation along the edge of the functional volume. Is there a way to eliminate this artifact? (see figures attached)
Moreover, is there a way to use the -native flag together with -per-run? I want to simultaneously measure the hippocampal activation (in native space) and cortical activity smoothed on the surface; but I want all the data to be processed the same way (-per-run), and currently the volume analysis forces me to use -per-session.
I haven't encountered any previously documented issues similar to this one. Please let me know if you have any thoughts.
1) FreeSurfer build stamp: freesurfer-darwin-macOS-7.3.2-20220804-6354275 2) Platform: Mac Studio M1 (macOS) 3) selxavg3-sess log: attached 4) analysis config file: attached
Thanks, Itzik
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