fmri_vox2reg

Description

FMRI_VOX2REG Averages voxel data within atlas ROIs to produce ROI-level data. Computes the mean across all voxels within each atlas ROI, producing a compact ROI-level representation. Useful for dimensionality reduction before connectivity or group-level analyses. Inverse of fmri_reg2vox.

Usage

reg = fmri_vox2reg(vox, atlas)

Inputs

  • VOX: Voxel-level data: (228453 x T) time series or (228453 x 1) map.

  • ATLAS: Atlas number (see atlas list below). Default: 1 (AAL).

Outputs

  • REG: ROI-level data (R x T) or (R x 1), where R is the number of ROIs in the selected atlas.

Examples

roi_ts = fmri_vox2reg(data, 3);         % Harvard-Oxford Cortical time series
roi_fc = corr(roi_ts');                  % ROI x ROI FC matrix
Atlas numbers:
1  = AAL / MarsBar (Automated Anatomical Labeling, 116 ROIs, default)
2  = Harvard-Oxford Subcortical Structural Atlas (21 ROIs)
3  = Harvard-Oxford Cortical Structural Atlas (48 ROIs)
4  = Cerebellar Atlas (MNI152, FLIRT affine, 28 ROIs)
5  = Cerebellar Atlas (MNI152, FNIRT nonlinear, 28 ROIs)
6  = JHU ICBM-DTI-81 White-Matter Labels (48 ROIs)
7  = JHU White-Matter Tractography Atlas (20 ROIs)
8  = Juelich Histological Atlas (62 ROIs)
9  = MNI Structural Atlas (9 ROIs)
10  = Oxford-Imanova Striatal Structural Atlas (3 ROIs)
11  = Oxford-Imanova Striatal Connectivity Atlas, 3 sub-regions
12  = Oxford-Imanova Striatal Connectivity Atlas, 7 sub-regions
13  = Oxford Thalamic Connectivity Probability Atlas (25 ROIs)
14  = Craddock Parcellation 200 ROI
15  = Craddock Parcellation 400 ROI
16  = Craddock Parcellation 500 ROI
17  = Craddock Parcellation 600 ROI
18  = Craddock Parcellation 950 ROI
19  = Brodmann Areas (48 regions)

See Also

  • fmri_reg2vox

  • fmri_regionmask

  • fmri_vox2reg