How our Brain approves of the Gaslighter's Attack:

Valuable info on our own brain and mind.
 

I apologize but the whole video hasn't been found online, so here are 4 clips from the episode, each about 2 minutes long. They are preview clips so you might not be required to sign in to PBS:

What drives this: the brain's actual pain when we're being excluded:

http://www.pbs.org/video/brain-david-eagleman-episode-5-clip-5/

What is "In groups vs Out groups"?

http://www.pbs.org/video/brain-david-eagleman-episode-5-in-group-out-group/

Genocide and the Brain 

http://www.pbs.org/video/brain-david-eagleman-episode-5-clip-6/

How does Empathy fit into this: fitting in, vs hating others

http://www.pbs.org/video/brain-david-eagleman-episode-5-clip-8/