Going back to Thomas Szasz’s assertion that a mental illness should produce an objectively verifiable lesion, in microbiology we see a lot of overlap in cause and symptoms. Anthrax and Chlamydia, for example, manifest differently depending on where they enter the body. Similar symptoms of STDs can arise from many different organisms. And much of our discomfort with infections is not a direct effect of the pathogen, but our immune response to them.
Take OCD, which has been given its own chapter in the DSMV, because it apparently involves the cingulate gyrus whereas Anxiety disorder seems to involve the amygdala more. I guess looking at it that way, there is no reason one couldn’t have both as a result of some deeper variation in neural physiology. In OCD, the compulsions neutralize the obsessions, and then it is the compulsions that often lead to decreased functionality.
Though I firmly believe in the contribution of experience to disorders, as I came from a family of nine children and the older set have their eccentricities but are highly functional. The younger set likewise, while a couple of us who were adolescents during our parents’ divorce were more affected.
It’s funny to me that I only now begin to understand the identification of Bipolar as a kind of global mood regulation disorder. I don’t know how I didn’t think of it that way before, and I’m still in the middle of reading about it. There’s the old analogy that headaches are not an aspirin deficiency, even though aspirin relieves them. I guess I always saw mood disorders as something that is happening, not something that would otherwise be prevented.