Structural Data

High-resolution anatomical MRI scans in the LAION-fMRI dataset.

Overview

The dataset includes high-resolution structural MRI scans for anatomical reference and normalization of functional data.

Anatomical Scans

T1-weighted Images

Acquisition Parameters:

Sequence: 3D T1-weighted MPRAGE (Magnetization Prepared Rapid Gradient Echo)
Field strength: 3 Tesla
Resolution: 1mm isotropic (1x1x1 mm³)
Matrix size: 256 x 256 x 176 (or similar)
TE (Echo Time): ~3.0 ms
TR (Repetition Time): ~2300 ms
TI (Inversion Time): ~900 ms
Flip angle: 9°

Image Characteristics:

Excellent gray/white matter contrast
Full brain coverage
Suitable for segmentation and surface reconstruction

File Organization

Structural data location:

sub-01/
└── anat/
    ├── sub-01_T1w.nii.gz              # T1-weighted anatomical image
    └── sub-01_T1w.json                # Acquisition parameters

Example JSON Metadata

{
    "Modality": "MR",
    "MagneticFieldStrength": 3,
    "Manufacturer": "Siemens",
    "ManufacturersModelName": "Prisma",
    "SequenceName": "MPRAGE",
    "RepetitionTime": 2.3,
    "EchoTime": 0.003,
    "InversionTime": 0.9,
    "FlipAngle": 9,
    "PixelBandwidth": 200,
    "SliceThickness": 1.0,
    "VoxelSize": [1.0, 1.0, 1.0]
}

Additional Structural Scans

T2-weighted (if available)

Some datasets may include T2-weighted images for additional contrast:

sub-01/
└── anat/
    ├── sub-01_T2w.nii.gz
    └── sub-01_T2w.json

FLAIR (if available)

sub-01/
└── anat/
    ├── sub-01_FLAIR.nii.gz
    └── sub-01_FLAIR.json