Indeed and this is more true for the retinotopic map. For cognitive there seems to be quite a bit of variability. In fact its not a trivial task to distinguish

Indeed and this is more true for the retinotopic map. For cognitive there seems to be quite a bit of variability. In fact its not a trivial task to distinguish a cognitively active brain from one that is in a waking but resting state. The comment that you quote wasn't made with reference to their work specifically but to any sufficiently accurate technology that can read through your eyes via the brain.