When Chico, who is sixteen years old and suffering from dementia, was helping us sort through our Christmas decorations for BarksGiving, he became particularly interested in a doggy bell collar. Rather than moving slowly, he started scampering around in no specific direction. Even though Chico's dementia causes him to wander without purpose, he still enjoys life and seeks human companionship. When Chico is happy, we are delighted, too.

No specific breeds are more prone to dementia; however, smaller dogs are more likely to develop the disease. This may be because smaller dogs tend to live longer, which gives the disease a better chance to develop. It's estimated that 68% of dogs over the age of fifteen show signs of dementia.

https://www.purina.com/articles/dog/senior-dog/health/dog-dementia