free advice of the day: is it brain-shaped?

Here's some advice: when starting a new analysis, and especially when troubleshooting problematic code, always open up a few of the input images and make sure they are brain-shaped. Many, many hours have been spent on complicated debugging when the problem was faulty input images.

At left is a screenshot from MRIcroN, my go-to program for quickly looking at images: yep, got data in the ranges I expected and in the shape of a brain.