My understanding is that negative symptoms can be caused by environmental conditions not sz alone. Naturally when someone is bed ridden, lonely, lost, deeply offended and otherwise, they’ll become depleted and withered away.
A human organism is vanquished in an environment of captivity and prodding will atrophy physically and thus mentally. I know that it is contrary to common understanding, but the environment is really inside the mind before it is outside around anyone. If the environment is in such a way that there are captors abusing you physically, depraving of nourishment, and so forth, then we know the results. Food, fitness activity, socially positive support, and knowledge combed with logic will due.
What most do not understand is that the sz is in an environment. There is what people like me called an interiorty of the mind, and if that virtual reality world inside of the brain is rendered in such away that it both abuses the self and behaves as an abused victim in such a bicameral state of mind (two chambered; Julian Jaynes), then it can be torture to do anything, speak to anyone, or go become anybody. It like a computerized, self containing mind prison inside without need for any real walls, administrators of vice, nor what you’d expect of an environment that would cause such distress as the article eludes to.
This is where the PTSD comes from, and that PTSD is heightened around people etc, so the person isolates quite often. Therefore the person becomes sedentary, and that augments so much of the negative symptoms.
Anyone with negative symptoms is likely isolated and forced to be so for any reason not just sz alone. There’s deprivation of activity, function, sociality, thinking, etc. The opposite is activity, thus the negative symptoms are solved.
I was highly athletic for throughout the heart of my sz years, and I was very much a daring ranger like active person. Naturally all of my neg syms vanished.