Even more, it's confounded by picking a control group and a study group and then asking "what's different?" without necessarily knowing why X should be different. What reason do they have to think white matter should be less? Afaik, none. It's something like p-hacking.
I'm inclined to agree with you. But, not having read the paper, they may have cited research that would discuss what sorts of damage would be likely to occur if it were a radio or sonic attack. I think that any radio or sonic attack would probably cause whole-brain damage, not localized lesions. Also white matter, gray matter volumes, DTI tract length and connectivity measures would be the first things I would look at for this sort of thing, so its not necessarily like you are p-hacking by looking for outcome measures that happen to be significant.
Even more, it's confounded by picking a control group and a study group and then asking "what's different?" without necessarily knowing why X should be different. What reason do they have to think white matter should be less? Afaik, none. It's something like p-hacking.