Disgust is an emotion; lack of disgust is not. You can only really measure how highly a person responds to disgust, not how highly they respond to anti-disgust.

Disgust is an emotion; lack of disgust is not. You can only really measure how highly a person responds to disgust, not how highly they respond to anti-disgust. This article does not even use the term "normal", however? I agree that it would be problematic to describe a population's response as "not normal" but I don't see it here.