Hello AFNI People,
I have a question about AFNI data analysis.
Would it be possible to conduct a Task-related functional connectivity analysis with AFNI? I have been analyzing with the software CONN so far, but the brain Atlas that I use has been quite difficult to locate my region of interest. SI was wondering if it would be possible to use AFNI to analysis this data!
The conditions I am looking at is the response inhibition effect on my experimental group and control group which are also divided into male and females. There will be 4 conditions randomly presented during the task, but I will actually only need to analysis between 2 primary task conditions. Overall, there will be 4 groups (Male Experimental, Female Experimental, Male Control and Female Control group) with 4 conditions in random intervals. Since I am mostly interested in the difference between the 2 primary conditions of the task, I assume it would become a 2 X 2 X 2 multimodal analysis.
I am very new to AFNI, and I was not sure there would it be a way to set up an analysis for each trial of the task. Please forgive me if I am indicating anything wrong.
Would it be possible to conduct a Task-related functional connectivity analysis with AFNI?
Unfortunately “functional connectivity” is a flashy but murky and imprecise term, and I have no idea what it exactly means in terms of modeling specifics. You mentioned ROI and trial-level analysis, but could you describe a little bit more in details as to what you’d like to achieve? PPI, beta series analysis, or something else?
Sorry for the late reply.
I have been looking into beta-series analysis and PPIs myself and I believe beta-series analysis could help me!
To answer your question, functional connectivity is the correlation of BOLD signals between the ROI and the whole brain. The averaged BOLD time series of all voxels in the ROI is compared against each voxel in the brain, and clusters of voxels that correlate highly enough to be significant. This would be a Seed-to-Voxel analysis.
The ROI I am trying to look at is the Anterior Cingulate Cortex (ACC), and I am looking to compare it to the whole brain to see if there is a functional connectivity between this region and the whole brain. I would like to see the FC in the ACC during cognitive tasks such as the Stroop task between male and female with certain experimental conditions. It will be a 2X2X2 (Biological Sex X Experimental condition X Stroop task condition) analysis. I could elaborate more if you would like.
I hope this helped!
Sojung, it’s up to you which method you want to pursue.
functional connectivity is the correlation of BOLD signals between the ROI and the whole brain. The averaged BOLD
time series of all voxels in the ROI is compared against each voxel in the brain, and clusters of voxels that correlate
highly enough to be significant. This would be a Seed-to-Voxel analysis.
Your definition is still pretty vague to me. Correlation under one particular task or in general? I’m not so sure in what sense we could help you in specifics.