Recent studies say as many as half of all people with serious mental illness suffer from a condition known as anosognosia (Greek for “no disease knowledge”).
The condition was first noticed a century ago in stroke patients, amputees and the blind. Because of a neurological disorder in the front of their brains, patients with anosognosia cannot appreciate that the affected body parts do not work properly.
Amputees will swear their missing limbs are there. The blind claim they can see.