This seems quite all over the place and I'm not sure what the point was. Was it that sometimes mental illness and creativity are coincident? Everything else seemed like a bunch of worldbuilding.
Creativity is highly correlated with mental illness because the kind of brain wiring required for creativity is a bit unstable. The article points to one such instability. Creative people are worse at filtering out "unnecessary" information.
Over all the uniting factor seems to be having an outsiders view of the world. Creativity, or mental illness will both give you a unique view of the world. Otherwise, the writing composition is beyond me