External Email - Use Caution
Hello,
I am conducting research using ECoG.
I want to accurately track the location of electrodes.
I am inputting data from a NIfTI file (size: 512, 512, 360, 1).
I already know the exact electrode location within the NIfTI file, e.g., (182, 274, 260).
The x, y, z values of this coordinate correspond to the raw fMRI scan, with x ranging from 0-512, y from 0-512, and z from 0-360.
I extracted the --vox2ras matrix from the 001.mgz file using mri_info.
I attempted to project the coordinates from the NIfTI file onto the generated pial surface, but I found a significant discrepancy.
What I need is not Talairach coordinates,
but a precise transformation of the electrode coordinates in the NIfTI space to their exact location on the subject's pial surface.
How can I achieve this?
Additionally, I noticed that the origin (0,0,0) of the generated pial surface does not align with the anterior commissure (AC).
I am curious about the coordinate system of the final mesh – is it simply the voxel-based x, y, z system, or is it in the RAS coordinate system?
Thank you.
Best regards,
Yonghyeon Gwon