Conditions Schizophrenia Pig!?

My oldest pig Cole has some weird behaviors that I can't seem to pin point and I think he might be Schizo maybe? We have had to remove him from the cage with the other pigs and put him on his own but he has play time every day. He stresses the other pigs out because he won't let them do certain things, and won't let Chewie go near his brother. He very aggressive to Chewie and Salem is afraid of him. Chewie has to stay at the opposite side of the cage when they are together otherwise Cole will chase him away and bite him. He will also prevent Salem from eating, drinking, playing etc. It's Like Cole thinks everything is evil and he has to protect all the pigs from it, especially Salem. It's like he's being told everything is bad for him except his food and water. Anything new i put in the cage he keeps everyone away from, even himself. Salem is small for his size because of it. Once we moved Cole out of the cage the other two jumped for joy, literally, and Salem has show massive growth towards venturing out into the open and not being afraid of us anymore. He still runs every now and then but He is finally calming down and being a sweetie.

When we do play time together it's very stressful, should I continue to do playtime together? Cole isn't sick and showed his own improvement health wise by being on his own. He's not as stressed and relaxes. He doesn't seem to like me at the moment and will bite at me, but not my Hubby so he deals with Cole most of the time. We have him set up so he can look down from his cage into the little pigs cage and he loves to sit on his bed/loft and watch the little ones.

The little ones, since the separation have begun to play more, and are way happier than before. They aren't hiding any more.

Any thoughts on this? Are there any mental conditions that Pigs can get? It doesn't fit just a standard behavior issue, that's why I ask.