Each kid has a value for each of the three levels of load and each of the two levels of chromophore. So age wouldn't vary between load 1, load 2 or load 3. Similarly, age wouldn't vary between chromophore 1 and chromophore 2.
As an e.g..:
Age(days) Load Chromophore Inputfile
1000 1 1 xyz1.nii
1000 1 2 xyz2.nii
1000 2 1 xyz3.nii
1000 2 2 xyz4.nii
1000 3 1 xyz5.nii
1000 3 2 xyz6.nii
2000 1 1 xyz7.nii
2000 1 2 xyz8.nii
2000 2 1 xyz9.nii
2000 2 2 xyz10.nii
2000 3 1 xyz11.nii
2000 3 2 xyz12.nii
.
.
.
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