The output from 3dinfo is below (3dhistlog says "command not found"). It looks to me like it's identifying 18 ROIs...

Dataset File: NEW_ROI_MASK_July3107+tlrc
Identifier Code: XYZ_iwIa9DZO26qReLMP8cdztw Creation Date: Tue Jul 31 09:48:38 2007
Dataset Type: Intensity (-fim)
Byte Order: LSB_FIRST [this CPU native = LSB_FIRST]
Storage Mode: BRIK file
Data Axes Orientation:
first (x) = Right-to-Left
second (y) = Anterior-to-Posterior
third (z) = Inferior-to-Superior [-orient RAI]
R-to-L extent: -80.000 [R] -to- 80.000 [L] -step- 1.000 mm [161 voxels]
A-to-P extent: -80.000 [A] -to- 110.000 [P] -step- 1.000 mm [191 voxels]
I-to-S extent: -65.000 -to- 85.000 [S] -step- 1.000 mm [151 voxels]
Number of values stored at each pixel = 1
-- At sub-brick #0 '#0' datum type is short: 0 to 18

----- HISTORY -----
[maura@v1280: Tue May 16 16:38:40 2006] to3d I.001 I.002 I.003 ... I.123 I.124
[maura@v1280: Tue May 16 16:42:19 2006] AFNI: markers were edited
[maurakurkjian@mfurey.nimh.nih.gov: Thu Feb 1 09:06:00 2007] 3dcopy anat.312.1+orig ss312-1.results/anat.312.1
[Julie@juliefrostb.local: Tue Jul 3 15:05:07 2007] afni: transformed to AC-PC Aligned
[Julie@juliefrostb.local: Tue Jul 3 15:07:26 2007] AFNI: markers were edited
[Julie@juliefrostb.local: Tue Jul 10 12:58:32 2007] afni: transformed to Talairach View
[Julie@juliefrostb.local: Tue Jul 10 12:58:48 2007] AFNI: resampled and rewritten
[Julie@juliefrostb.local: Thu Jul 26 16:43:41 2007] 3dcopy anat.312.1+tlrc GENERIC.anat
[Julie@juliefrostb.local: Tue Jul 31 09:48:38 2007] Drawing plugin COPY: Fill->Zero Type->Func