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Data

EPI Warp

Under Construction

Notes about the Data

All subjects have been fully anonymized. They are identified only by a subject number.

Data here is formatted as-per the DTI requirements of FSL. Each tarball below contains 4 directories containing the following identifying information: AP_m, AP_p, RL_m and RL_p, where RL=right-left frequency encode direction and AP=anterior-posterior frequency encode direction, and m=minus blip and p=plus blip.

In each directory, there is a file entitled "data.img/.hdr" which is a 4D analyze file containing all diffusion weighted images and b0 images in the order in which they were originally acquired. There are also files entitled "bvecs" and "bvals" which contain the bvectors and bvalues as-per FSL.

This data has been corrected for eddy current distortions and motion artifacts using the DIFF_PREP module of TORTOISE. This is indicated by the use of the symbol "rpd" in each directory name. Uncorrected raw data may be made available in the future.

Please contact Lindsay Walker for EPI Warp data.

Data Downloads

Below are several images provided as part of the paper Effects of Physiological Noise in Population Analysis of Diffusion Tensor MRI data submitted to NeuroImage. All images are in NIfTI format, gzipped unless otherwise noted.

mean FA (non-linear least squares fitting)
standard deviation of FA
mean tensor (from the DTITK software)
ORP map

Cluster maps (from FSL voxel-wise analysis) - When viewed in FSLView the viewable range should be set to min=0.95 max=1 in order to see only the statistically significant (p<0.05) clusters. These are best viewed overlaid on the mean FA map in order to appreciate the anatomical locations of the clusters.