Hi,

I am having a small problem here with only 1 subject out of a dataset that contains 25 subjects. I ran the following preprocessing script for a resting-state session (one run per subject).

afni_proc.py \
-subj_id ${subject}_Rest \
-out_dir $directory/Results \
-dsets \
$directory_raw/restto3d+orig \
-blocks despike ricor tshift align tlrc volreg mask blur regress \
-copy_anat $directory_SSwarper/anatSS.$subject.nii \
-anat_has_skull no \
-ricor_regs $directory/Physiological_Regressors.slibase.1D \
-ricor_regress_method per-run \
-tcat_remove_first_trs 4 \
-align_opts_aea -cost lpa -big_move \
-volreg_align_e2a \
-volreg_align_to MIN_OUTLIER \
-volreg_tlrc_warp -tlrc_base MNI152_2009_template_SSW.nii.gz \
-tlrc_NL_warp \
-tlrc_NL_warped_dsets \
$directory_SSwarper/anatQQ.$subject.nii \
$directory_SSwarper/anatQQ.$subject.aff12.1D \
$directory_SSwarper/anatQQ.${subject}_WARP.nii \
-volreg_post_vr_allin yes \
-volreg_pvra_base_index MIN_OUTLIER \
-mask_segment_anat yes \
-mask_segment_erode yes \
-regress_anaticor \
-regress_ROI WMe \
-regress_apply_mot_types demean deriv \
-regress_motion_per_run \
-regress_censor_motion 0.2 \
-regress_censor_outliers 0.05 \
-blur_size 6.0 \
-regress_est_blur_epits \
-regress_est_blur_errts \
-html_review_style pythonic \
-execute

The results are good, beside for one single subject (6). When I open the .errts output file by AFNI proc to inspect the time-series and visual results, all possible images (axial, sagittal, and coronal) remain fully black on all slices. I just realized this by accident because further measurements (like the power-law exponent) showed extremely low values for this subject. Only then I rechecked the errts file for this subject and realized the problem.

Some more information for subject 6 (the one with the problem)
- The raw data of the functional and anatomical scans look good.
- Results of SSwarper and all anatomical files look good.
- All previous steps of the preprocessing (volreg, ricor, blur, etc.) look good.
- Only the .errts (both anaticor and tproject) is then suddenly fully "gone".
- The time-series of the .errts file is there though!

What could the problem be? I already ran the preprocessing again, just in case something went wrong with my computer. But the problem remains. I would like to use this subject instead of exluding it from the study.

Thanks for any input,
Philipp