An autoimmune reaction whereby her immune system attacks the myelination of axons in her nervous system. This means that Mrs. Archer's immune systems has recognized the myelinated axons of her nervous system as "dangerous" and has set about "attacking" them as if they were foreign invaders (e.g., infection). This results in the myelination axons being damaged resulting in a plethora of detrimental effects including motor issues, cognitive issues, and affective issues.