I have renamed the three posts entitled "Diagnosing artifacts in fMRI data: Part x" to be "Physics for understanding fMRI artifacts: Part x." I am developing new posts in the series and through post seven at least the content is all quite theoretical; I'm not actually discussing artifacts or showing data! (But don't worry, I'm limiting the content to the essential concepts required to understand and differentiate fMRI artifacts. It's not going to be an entire MRI physics course!)
Once I've concluded this background series of physics posts (there are another eight or nine posts to come) I'll start a new series that will be entitled something suitable for actual artifact recognition (with data!), along the lines of the original title of the series. Hopefully this re-categorization will allow future readers to establish suitable paths through the posts, when a strictly chronological path probably won't be the best one.