Puppy born with mental issues?

[Laurelin]

Trey's parents were very stable, so were his siblings. He is by far the best bred dog I've ever owned. I'm not sure why he wasn't stable. He was so simple, I mean really he didn't have an intelligent bone in his body. Terrified of everything, bit me many a time. With him though he could not ever understand communication by another dog or a person. He thought everyone was being aggressive when they weren't and he'd react defensively to them. If a dog would try to play, he'd freeze up and completely shut down. Same with a person trying to play with him. For the longest time, any kind of attention would shut him down. He was always off in his own world. He gave off an air of being very ditzy because of that. No vet could ever explain his behavior. We ran so many blood tests but nothing was 'wrong'.

I wish I'd known about Amitriptyline while he was alive. Maybe it could have helped him too.