Senior dogs aren’t as spry as they used to be. They have less energy, and their achy joints make certain activities more challenging. While it’s disheartening to see your pup slow down, changes to their health are all part of the natural aging process.

A dog’s body isn’t the only thing that begins to slow down, though. Approximately one in three dogs will experience cognitive decline once they hit their senior years. Since this condition is so prevalent, pet parents should familiarize themselves with how to detect it.

Here are the eight most common signs of cognitive decline in senior dogs.

1. Forgetfulness: As dogs get older, their brain cells start to deteriorate. This can affect a dog’s ability to remember parts of their daily routine. If you walk the same route every day, you might be surprised to see your senior dog turn in the wrong direction. Dogs with cognitive decline might also forget which way a door opens or where their food bowls are located in the house. Lapses in memory are a direct result of age-related cognitive decline.
2. Training difficulties: Cognitive decline makes it harder for senior dogs to learn new tasks. While learning is possible at every stage in life, dogs with cognitive decline struggle to retain information about tricks or commands. It’s important for pet parents to recognize that failure to execute commands isn’t an act of disobedience. Senior dogs are less capable of forming new synapses in the brain, which causes them to forget a command shortly after they’re taught it.
3. Disregard for basic commands: Short-term memory isn’t the only part of the brain that dwindles with age. Dogs with cognitive decline lose some of their long-term memory, as well. Commands that used to come easily now seem almost impossible. Your senior dog might not understand what you want when you give the usual signals for “sit,” “stay” or “drop it.” When you call out to your dog, they might not respond to their name anymore. Again, this is due to the breakdown of brain cells rather than disobedience.
4. Accidents in the house: In addition to forgetting basic commands, dogs with cognitive decline often revert back to behaviors they exhibited as puppies. When your dog first arrived home, you had to teach them the house rules, such as relieving themselves in the back yard. Senior dogs often develop fecal and urinary incontinence because they forget where it’s appropriate to eliminate. As a result, you might have to clean up more accidents around your home.
5. Changes in behavior: A senior dog might not seem like their normal self. Cognitive decline can trigger changes in behavior that affect how the dog interacts with family members and other pets. A friendly, sweet-tempered pup can gradually become guarded and irritable due to a shift in brain function. There’s always a reason for behavioral changes, and in senior dogs, cognitive decline is often the answer.
6. Anxiety: Regardless of your dog’s typical personality, anxiety is a common symptom observed in many cases of cognitive decline. Your senior dog might seem a lot clingier than usual. You might come home to find trash bins knocked over or bite marks on the furniture. Restlessness and excessive barking are also signs of anxiety in senior dogs. Your dog might seem anxious for the first time, but cognitive decline can also worsen anxiety that was already present.
7. Shifts in their sleep cycle: Much like with humans, cognitive decline in senior dogs can lead to disrupted sleeping patterns. You might hear Fido pacing around at night or howling while everyone else is trying to sleep. Dogs with a disrupted sleep cycle also nap more than usual during the day. Take note of any changes to your dog’s sleep-wake patterns, as this could be a sign of cognitive decline.
8. Resistance to physical activity: Frequent napping often coincides with a reluctance to play or go for walks. Dogs with cognitive decline often resist their owners’ efforts to initiate playtime. Some senior dogs might lose interest in activities they used to enjoy, such as hiking, swimming or visiting the dog park. Cognitive decline is one of many possible explanations for sedentary behavior, so consult your vet for a proper diagnosis.

Cognitive decline affects many senior dogs, and the signs can gradually settle in over time. Dogs with cognitive decline are still very much capable of leading healthy and fulfilling lives. The sooner you detect the warning signs, the sooner your senior pup can receive treatment. Early diagnosis can slow the progression of cognitive decline and keep a dog’s mind sharp well into their senior years.