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Dear AFNI users-
We are very pleased to announce that the new AFNI Message Board framework is up! Please join us at:
https://discuss.afni.nimh.nih.gov
Existing user accounts have been migrated, so returning users can login by requesting a password reset. New users can create accounts, as well, through a standard account creation process. Please note that these setup emails might initially go to spam folders (esp. for NIH users!), so please check those locations in the beginning.
The current Message Board discussion threads have been migrated to the new framework. The current Message Board will remain visible, but read-only, for a little while.
Sincerely,
AFNI HQ
History of AFNI updates
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Hi Rick,
Yes, that does make sense. I hadn't thought about the fact that slice time correction aligns everything to the start of the TR and that some slices would be finished before a stimulus occurring after the start of that final TR. I agree that it doesn't make much sense to present stimuli this late - I've never encountered this issue in previous fMRI work because we have
by
kwills01
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AFNI Message Board
Hello,
I am working on re-analyzing some fMRI data, which was previously analyzed using SPM. 3dinfo shows that each of my runs are 173 time points. At 2 seconds a TR, I assume this should mean that the runs are 346 seconds each. My output from 3dDeconvolve confirms that the longest run is 346.0 seconds, and all the runs should be the same length. However, 3dDeconvolve appears to be cutting
by
kwills01
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AFNI Message Board
I'll try a new model. My problem is that I have a lot of runs that don't have any errors in them. I've been using a single timing file for each regressor in which each line represents a run (there are 8 runs in my experiment, so each timing file has 8 lines). How can I set up my error stim files so even when no errors occur, 3ddeconvolve is able to track with the correct run?
by
kwills01
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AFNI Message Board
As part of my fMRI analysis, I performed a regression using the beta weights from individual trials to predict behavioral accuracy. I found that higher activity in one of my ROIs predicts errors. As a visual for this result, I would like to plot an average time series of the error versus the correct trials in this region.
However, since task accuracy was quite high, my original model did n
by
kwills01
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AFNI Message Board
Hi Gang,
I am using task-related data, so I ran a PPI analysis, but upon showing my results to my PI, her question was this: if I found a positive PPI indicating that a seed region increases the contrast between conditions A and B in a particular target region, could that mean that the seed and the target show a stronger negative correlation in condition A than condition B?
Based on this
by
kwills01
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AFNI Message Board
Hi Gang,
Thank you for your response. I did censor out some data points because of motion. What alternative methods would you recommend to clean up the data without this affecting it?
I am doing a simple correlation analysis. Following these guidelines:
Thank you!
Katelyn Wills
by
kwills01
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AFNI Message Board
I am trying to run a functional connectivity analysis on my data. When I run 3dSynthesize, several massive spikes are showing up in the resulting time course that have a value of 0. Of course when I subtract this from the original time course using 3dcalc, the resulting "clean" data set reflects that and barely resembles a time course. Most of the values are small (as I would expect)
by
kwills01
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AFNI Message Board