Creating Masks In FSL

Due to a high number of requests (three), I have made some walkthroughs about how to create masks in FSL. There are a few different ways to do this:

  1. Anatomical ROI: These masks are generated from anatomical regions labeled by atlases. For example, you may decide to focus only on voxels within the V1 area of visual cortex. Using an atlas will create a mask of that region, based on the atlas-defined anatomical boundaries in a standardized space.
  2. Functional ROI (or contrast ROI): This is a mask created from a contrast thresholded at a specific statistic value. For example, you may wish to focus only on voxels that pass cluster correction for the contrast of left button presses minus right button presses.
  3. Painting ROIs: This is where the real fun starts; instead of being confined by the limitations of anatomical or contrast boundaries, let your imagination run wild and simply paint where you want to do an ROI analysis. Similar to what you did in first grade, but more high-tech and with less puking after eating your crayons. (Is it my fault that Razzmatazz Red sounds so delicious?)
Demonstrations of each approach can be found in the following videos:

 Anatomical ROIs

Functional ROIs

 ROIs created from FSLview. Pretend like you're Bob Ross.

FSL Tutorial: Part 1 (of many)

I recently started testing out FSL to see if it has any advantages over other fMRI analysis packages, and decided to document everything on Youtube as I go along. The concepts are the same as any other package (AFNI, SPM, etc), but the terminology is slightly different, and driving it from the command line is not as intuitive as you would think. Plus, they use a ton of acronyms for everything, which, to be honest, kind of pisses me off; I don't like it when they try to be cute and funny like that. The quotes and sonnets generated by AFNI after exiting the program, however, are sophisticated and endearing. One of my favorites: "Each goodbye makes the next hello closer!"

In any case, here is the first, introductory tutorial I made about FSL. I realized from searching around on Youtube that hardly any fMRI analysis tutorial videos exist, and that this is a market that sorely needs to be filled. A series of walkthroughs and online lessons using actual data, in my opinion, would be far more useful at illustrating the fundamentals of fMRI data analysis than only having manuals (although those are extremely important as well, and I would recommend that anyone getting started in the field read them so that they can needlessly suffer as I did).

I will attempt to upload more on a regular basis, and start to get some coherent lesson plan going which allows the beginner to get off the ground and understand what the hell is going on. True story: It took me at least three years to fully comprehend what a beta weight was. Three years. I'm not going to blame it all on Smirnoff Ice, but it certainly didn't help.

Note: I suggest hitting fullscreen mode and viewing at a higher resolution (360p or 480p) in order to better see the text in the terminal window.

Also, the example data for these tutorials can be found here.