Everything you Need to Know about Narcissists, Psychopaths, and Abuse - click on this link:
http://www.narcissistic-abuse.com/faq1.html
Like a trapped animal, the narcissist is forever on the lookout: was this comment meant to demean him? Was this utterance a deliberate attack? Gradually, his mind turns into a chaotic battlefield of paranoia and ideas of reference until he loses touch with reality and retreats to his own world of fantasised and unchallenged grandiosity.
But, here's the twist:
When the disagreement or criticism or disapproval or approbation are public, though, the narcissist tends to regard them as Narcissistic Supply! Only when they are expressed in private -- does the narcissist rage against them.
(From the book "Malignant Self-love: Narcissism Revisited" by Sam Vaknin - Click on this link to purchase the print book, or 16 e-books, or 2 DVDs with 12 hours of video lectures on narcissists, psychopaths, and abuse in relationships:
http://www.narcissistic-abuse.com/thebook.html)