fmri_mni2sub

Description

FMRI_MNI2SUB Converts MNI coordinates (mm) to voxel subscripts. Converts one or more MNI152 coordinates (in mm) to voxel subscripts in the 91x109x91 MATLAB 1-based subscript space, using the standard 2mm MNI152 template. Rounds to the nearest voxel centre.

Usage

sub = fmri_mni2sub(mni)

Inputs

  • MNI: MNI coordinates in mm, (N x 3) matrix: [x1 y1 z1; x2 y2 z2; …].

Outputs

  • SUB: Voxel subscripts (rounded), (N x 3) matrix: [x y z].

  • 1: based MATLAB indices, x in [1 91], y in [1 109], z in [1 91].

Examples

sub = fmri_mni2sub([0 0 0]);             % returns [46 64 37]
sub = fmri_mni2sub([-42 -18 60]);        % motor cortex
mask = fmri_spheremask(fmri_mni2sub([20 -58 18]), 5);

Notes

  • MNI [0 0 0] maps to subscript [46 64 37].

  • Coordinates outside the brain volume are not clipped — use with care.

  • Inverse function: fmri_sub2mni.

See Also

  • fmri_sub2mni

  • fmri_mni2tal

  • fmri_spheremask

  • fmri_regionmask