Dogs are amazing animals, often exhibiting some of the same personality traits and nuances as humans. It is likely because of these traits and behaviors that people become so closely attached to their canine companions. Unlike humans though, it is difficult to study the inner-workings of a dog’s mind. Still, it is evident that dogs do have long-term memory capability even though it varies from that of long-term human memory.
Long-term memory is the storage of information for retrieval at a later date. It is what allows a person to know that a dog has four legs without thinking about it. Humans obviously have a larger capacity this type of memory and may organize and store information differently than dogs. Dogs display their long-term memory capability by the way they learn to do things that are not in their nature. For example, house-training is a behavior that is not natural to dogs, but they are still able to learn.
When information becomes stored in long-term memory, neurons are firing in the brain. This type of memory is directly related to lifelong learning and dogs are most definitely capable of learning. It therefore stands to reason that dogs do have long lasting memories. Dogs learn by association between behaviors and the responses of their owners or other factors in their environment.
If a dog is praised for his behavior, he makes a positive association and stores that association in his long-term memory bank. Similar to humans, praise and reward seem to help dogs move information quickly from short-term to long-term memory. Dog training, especially of therapy and helper dogs, relies on a dog's ability to learn quickly and retain what they have learned.