The mind is the brain, that's how I see it. If the mind appears defective in some obvious way, the brain must be affected physically by something. The most obvious is brain damage, physical damage, injury, lesion, etc. The change is obvious for all to see, the person is not himself anymore. It's only a small leap to go from there to where anything can have a similar effect on the brain and thus the mind. Consider that famous brain fog that lifts once we cut out wheat, or a similar brain fog that comes in when we get a cold with chills and fever. We are certainly not ourselves, something's affecting our behavior. Personally, I experienced intense pain at some point, I couldn't think straight, I was not myself, the pain was affecting my brain and in turn my behavior. Once the pain was gone, I could think clearly again. I also experienced significant improvements in cognitive ability when I initially went all-meat, which suggests something I was eating was affecting my brain physically, and that's been my conclusion from that point on. Scurvy is said to change one's personality, a person becomes more cynical. Dietary deficiencies like B12 for example have a definite effect on behavior, by affecting brain function. The gender hormones testosterone and estrogen have a strong effect on our behavior, especially with a deficiency of those hormones, with depression as a symptom of low testosterone for example.

If there is a paradigm shift that needs to happen, it's the one where instead of looking merely at the brain itself as the only site where any possible problem could be present, it's to look at the entire body as a whole with all its mechanisms and systems, and then at the environment and its many things that have the ability to affect the brain above and beyond the classical "you're stressed out because of such and such, take a break". In spite of the obvious fact that by excluding certain foods like sugar and wheat, and by adding other foods like meat and fat, with the ketogenic diet used to treat a brain disorder, the current paradigm is still one that says it's all in the brain, it's genetic, there's nothing we can do, it's incurable. But most important this says whoever is an expert in these things is saying "we don't know the cause, otherwise we'd have licked it by now". Cuz we have licked most infectious diseases by now, right? We know the cause of those, it's a microscopic lifeform or another. We know how to treat the cause directly. That's the paradigm for infectious diseases, very different from the one for brain disorders.