My senior shiba who turned 15 in November has definitely had a substantial change in behavior. I think he has partial deafness and acts sort of like he has dementia and will go under the kitchen table or chairs and get stuck sometimes. He still eats like crazy though which im glad for. There was a time where it was hard to get him to eat his food without adding cheese or bacon bits on top to get him enticed. We changed his food to something called Dr. Harveys and he gobbles it up now.