Even a year after weight restoration, the test subjects' brains didn't see much difference between positive and negative reward.
They were, essentially, stumbling blind, unable to learn from experience. That's no fun. No happy face for doing well, no warning bell to alert of danger.
Positive and negative felt the same. Imagine responding the same to a slap as a hug. Imagine how chaotic and annoying it would be if things seemed to go right or wrong around you without rhyme or reason. You get sicker and people get more frustrated with you, but it doesn't matter what you do. You would feel - does this sound familiar? - as if you "have no control."
What does this mean for caregivers? Patience. Love. The long view. And protect our loved ones from negative consequences of the ED until the switch gets fixed or there is a work-around in place.