That's my impression. Sarin and cyclosarin are organophosphates, like most pesticides, IIRC. I wonder if any other studies of organophosphates and brain imaging can be found. Here's a link to the abstract, it seems, of the article in question.
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I wasn’t there, but from what I heard this is what “Gulf War Syndrome” was. The Army blew up an ammo dump and the nerve gas blew far and wide because it is heavier than air and there are no trees to block the wind. I am surprised the truth has finally come out.