help > Seed-based rs-frmi voxels fall within the seed mask
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Jul 15, 2019 10:07 PM | Isadora Olive - UWO
Seed-based rs-frmi voxels fall within the seed mask
Hello!
I've made a seed-based rs-fmri analysis of a dataset with the seed defined by a mask in the inferior frontal lobe. I observed strong significant results when comparing a patient's group 1 with patient's group 2, and when comparing patient's group 1 with healthy controls. Nevertheless, many of these results fell within the inferior frontal lobe mask I've employed. Is this acceptable? Or does it indicate an error, and which one would it be?
Thank you for your help,
I've made a seed-based rs-fmri analysis of a dataset with the seed defined by a mask in the inferior frontal lobe. I observed strong significant results when comparing a patient's group 1 with patient's group 2, and when comparing patient's group 1 with healthy controls. Nevertheless, many of these results fell within the inferior frontal lobe mask I've employed. Is this acceptable? Or does it indicate an error, and which one would it be?
Thank you for your help,
Jul 20, 2019 11:07 AM | Alfonso Nieto-Castanon - Boston University
RE: Seed-based rs-frmi voxels fall within the seed mask
Hi Isadora,
That looks perfectly fine, typically that is interpreted as different levels of regional homogeneity or coherence within the seed region (as seed-to-voxel analyses measure the correlation between the average BOLD signal within a seed ROI and each individual voxel, so more homogeneous regions show higher correlations between the seed ROI and individual voxels within the same area)
That said, inferior frontal areas are particularly hard areas to look at because they are often most affected by susceptibility artifacts such as spatial distortions and signal dropout caused by proximity with air sinuses, so that would be a potential confounding effect to take into account here when analyzing or interpreting these data
Hope this helps
Alfonso
Originally posted by Isadora Olive:
That looks perfectly fine, typically that is interpreted as different levels of regional homogeneity or coherence within the seed region (as seed-to-voxel analyses measure the correlation between the average BOLD signal within a seed ROI and each individual voxel, so more homogeneous regions show higher correlations between the seed ROI and individual voxels within the same area)
That said, inferior frontal areas are particularly hard areas to look at because they are often most affected by susceptibility artifacts such as spatial distortions and signal dropout caused by proximity with air sinuses, so that would be a potential confounding effect to take into account here when analyzing or interpreting these data
Hope this helps
Alfonso
Originally posted by Isadora Olive:
Hello!
I've made a seed-based rs-fmri analysis of a dataset with the seed defined by a mask in the inferior frontal lobe. I observed strong significant results when comparing a patient's group 1 with patient's group 2, and when comparing patient's group 1 with healthy controls. Nevertheless, many of these results fell within the inferior frontal lobe mask I've employed. Is this acceptable? Or does it indicate an error, and which one would it be?
Thank you for your help,
I've made a seed-based rs-fmri analysis of a dataset with the seed defined by a mask in the inferior frontal lobe. I observed strong significant results when comparing a patient's group 1 with patient's group 2, and when comparing patient's group 1 with healthy controls. Nevertheless, many of these results fell within the inferior frontal lobe mask I've employed. Is this acceptable? Or does it indicate an error, and which one would it be?
Thank you for your help,