Lifelong learning is not just good for people, it is also good for dogs. Dogs are capable of learning even in old age, and constant brain training and mental problem-solving create positive emotions and slow the natural pace of mental deterioration. Unlike puppies or young dogs, however, old dogs are almost never trained or challenged mentally. Senior dogs are usually perfectly integrated into our lives and we often forgive them any disobedience or stubbornness. In addition, due to their increasing physical limitations, we usually spare old dogs the sort of training we might expect from young animals.