These days there's plenty of research around that tells us how ageing affects our brains and what we can do to keep our minds sharp.
As it turns out, our pets can get foggy and forgetful in their old age too - and scientists are discovering new ways to help them stay sharp as well.
A dog is considered senior from the age of seven, and from this age on you might start to notice your pooch wants to sleep more often; they might find it harder to get on and off the couch (as the early stages of arthritis sets in), and they can become grumpier because they're in a bit of pain and discomfort. They can also start to develop liver and kidney issues.
But what's been less recognised until now is the cognitive changes. Older dogs don't utilise glucose as well, and this is the reason behind their brain function degenerating, explains SPCA vet ambassador Shalsee Vigeant.
But how do you tell if your dog has started getting forgetful? What would their behaviour be like if they were no longer as 'with it'?
"The fact that they sleep more and they don't get as excited about things as they used to... we now know these are changes related to brain function," Shalsee explains. "Your dog may also become more anxious or less attentive."
The good news is pet owners can slow brain degeneration by feeding their pets specially formulated pet food containing certain enhanced botanical oils. Purina has a new Pro Plan Bright Mind range that includes these oils (Medium Chain Triglyceride) which support brain function in senior dogs.
"We never realised before that we still needed to feed the brain to keep the brain active, just like giving your body the food it needs - and we now know it's just as important in our pets," Shalsee says. "That's brand new research and a big area that will be able to give pets a longer life and a better quality of life."
So feeding them the right foods to support brain function - is there anything else can we do?
Continue to exercise them. For many dogs going for a walk is the highlight of their day. But keep an eye on how stiff they are in the mornings and evenings and consider reducing the length of their walks.
Give them regular check-ups at the vet
Many pet owners only take their animals to the vet when they're due for a vaccine or are injured or unwell. But Shalsee advises regular check-ups for animals over the age of seven so you can catch issues early and make your pet as comfortable as possible.
An older animal might require a more comfy bed. If they've been outside animals, consider bringing them inside at night, especially in winter. Wherever their sleeping space is, it needs to be warm and dry. If they're allowed on furniture, make sure they can get up and down easily.
Continue to make them part of your family
Just like us, dogs are social animals that do best with social interaction and lots of love and cuddles and attention. Keep showing them how much you love them.