Need Help Getting Anxious Dog to Respond to Basic Commands

After fostering and rehabilitating dogs for quite some time, I have finally ran in to a dog that has left stumped. It is a chihuahua mix male, who I happily took from irresponsible owners who didn't want him anymore. He's a little over a year, and during his life it seems like he never received any training - actually his previous owners literally told me "It should be fine if you just leave him in his cage all day, and if he whines just yell at him till he stops, that's what we do".

He does not respond to a name or any basic commands, and is not house trained. This was fine, I've managed to over come these issues with many dogs in the past. But, most dogs are at least eager to learn after some positive reinforcement. My problem with this dog is that he does not respond to anything. He doesn't care about being pet, he doesn't care about food or treats.

Really I feel mean saying it, but to be honest he has a very glazed over look in his eyes that makes it seem like he's not even paying attention to what is going on around him. I thought at first he was just adjusting to a new owner, but I've never had a dog that's taken this long to adjust. Literally all he wants to do is pee on everything, whine or bark, or stare at my other dogs (literally just sit near them and stare) to the point that my other dogs don't feel comfortable around him. I know they don't because recently they've started growling at him and literally running away until I have to intervene because he won't stop running after them and whining.

Right now, he is laying in bed with me fighting his sleep - his eyes are blood shot - and just whining while he stares off at nothing. It's really odd behavior. So, for about a week now I've worked on simply teaching him lay down, with absolutely no results. No joke, he literally has shown no change. I'm growing concerned about possible mental issues that may be too advanced for my experience. I'm really at a loss.

Is there anyone that has experienced this?
Asked Sep 04, 2017
Edited Sep 04, 2017

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