But are heart disease and cancer "somewhat more treatable" inherently, or because more resources have been devoted to finding and testing treatments that work for them?
Or both. Brain is arguably the most complex system in the human body, and understanding of how it works is, AFAIK (I'm not an MD or a scientist), still not very comprehensive, much less than, for example, the heart. Treating extremely complex system which we don't know how exactly it works and are very limited in experiments (pigs or mice can have hearts not unlike ours, but their brains probably differ much more and while one can observe heart disease in mice, I wonder how you could observe mental illness like schizophrenia?) would probably be not easy at all.
