Elderly basset barking during night and morning?

So I have a basset hound who is 14 and the vets have said its most likely dementia that he has, (that was a while ago, maybe a year). When he’s being put to bed he would normally bark for a bit and then settle down. But now he barks for about two hours straight. Tonight he has seemingly barked from 10pm till about 2am. Its 3am and I have anxiety and insomnia and he’s starting again. What can I do to settle him? He has food and water and bedding along with toys. I’m scared of the neighbours reaction.