For me, Parkinson's disease is a fait accompli, and by definition takes over some of my time and thoughts, and influences my behavior.
There is that constant trio: disease-patient-physician (and medication), highly consuming and threatening to become the central axis of my life.
My ability to establish a counter-weight has forged its own two creative channels: writing and wood carving. I did engage in both prior to my diagnosis, but at a certain point, soon afterwards, my activity in both areas diminished.
Regaining myself, I realized how significant they are in my life, and that I must not give them up. I then took them up again all the more vitally. My writing has transformed, turning now mainly to humor and dealing directly with Parkinson's disease.
The essentials in writing, to my mind, are creative thinking, dealing with new material, exploring new ideas, the fruitful handling of knowledge stored in our archive (brain!) and used for analysis and creating new structures; renewed interest in various topics and mechanisms; the feeling of capacity still present in us despite physical decline; our contribution to the community and to our readers.
Essentials of wood-carving, besides thinking ahead and planning, the ability to create abstract works unbound to figurative precision, that will reveal our ideas to others.
Above and beyond all of this, both fields grant me wonderful bonus called fun. What more could I wish?