Negative symptoms are probably not progressive over time but with the time being, they are rather mainly an synergic addition/mix of :
- real negative symptoms of schizophrenia
- iatrogenic slowing and depressing effects of medication
- after-effects and/or effects of post-psychotic or any type of depression
- avoidance of cognitive overload
- low-functioning enhanced by loneliness, social withdrawal, centralization habits
- burnout due to energy-costing defenses against positive symptoms/dissociation
- obesity or overweight
- the whole goes on the foreground as positives are less loud
I don’t know if negatives worsen or get better but new medications like abilify or vraylar are stimulant and can activate anxiety.