It's remarkable that this works, and it's equally remarkable that the authors succeeded using a (deliberately) naive approach with the fMRI data. I was just teaching the visual system to students over the last few weeks: cognitive neuroscience/neuropsychology can tell us a lot about what brain systems should be involved here. It's such a tempting research domain to dive into using a more sophisticated approach, but then again, maybe the authors' simpler data-driven method is a strength.