My 10 year old pug seems to zone out

I have a 10 year old pug who will stand in one place for several minutes at a time and just be out there in her own world. It is mostly at night this happens. Do dogs suffer with dementia?? She doesn't respond when you call her when she is in this state. If so what can we do for her, we love her so much and it deeply saddens me to see her like this. Help please.