AuntieLeela

I think 'arthritis of the brain' might refer to Rheumatoid Vasculitis, it's a rare complication of severe, long term RA. It causes inflammation of the blood vessels. In the brain vasculitis can cause alot of trouble; headaches, problems thinking clearly or "brain fog" and stroke-like symptoms. Treatment is usually corticosteroids (brands like prednisone or decadron) and drugs like methotrexate (brand name Rheumatrex) or azathiaprine (brand name Imuran or Azasan).

Other diseases can cause various forms of vasculitis too and can effect all parts of the body, like Giant Cell Arteritis, Polymyalgia Rheumatica, Central nervous system (CNS) vasculitis and Polyarteritis Nodosa.

Here's an info page on vasculitis:
http://www.nhlbi.nih.gov/health/dci/Diseases/vas/vas_whatis.html