You've raised an important point. People with FASD are often much more sensitive to external stimulation, so they often overreact. I am regularly in touch with a particular inmate with FASD. He said he was in an institution where, when the guards came in, they said, “Okay, we're coming in. This is what we're doing,” and everything was fine. He was in another institution where guards would come in and just grab him, and he reacted inappropriately. Those are the sorts of things that will put you in solitary.
The other problem is that people with FASD are often highly subject to manipulation. They will also end up there for disciplinary charges, often because they will take responsibility for the acts of other people. Certainly, we know we have a lot of people in the prison system with FASD and other cognitive deficits. They're being put in solitary and that is just exacerbating their problems.