Brain Aging in Dogs

A dog’s brain will typically weigh less as the dog ages; this is mainly the result of neuronal death in the cerebral hemispheres. As the dog ages, this will lead to a decrease in production and an increase in the destruction of central neurotransmitters. While the aging brain of a dog will result in changes in his behavior, a dog can also experience canine cognitive dysfunction syndrome (also called canine dementia); in fact, available data points to 25% of dogs over the age of 10 displaying at least one of the main symptoms linked to brain aging.

In dogs of 15 year of age and above, more than 60% are impacted. Canine cognitive dysfunction syndrome has similarities to Alzheimer’s disease that impacts humans and can cause confusion, disorientation, memory loss and changes in personality.

Canine cognitive dysfunction syndrome, also called canine dementia, can result from brain aging in dogs, leading to confusion, disorientation, memory loss and personality changes.

While brain aging can lead to personality changes in your dog, additional symptoms may be present should your dog be experiencing canine cognitive dysfunction syndrome. You may observe the following symptoms:

• Confusion
• Less responsive than usual
• Getting lost in corners or staring at a door waiting for it to open
• Not responding to his or her name
• Indoor accidents
• Less social
• Barking for no apparent reason
• Not recognizing people or places that in the past were familiar

As some of these symptoms may be present in other conditions (for example, hearing loss), it is best to seek veterinary assistance. 

Types

Brain aging can lead to behavior changes in dogs. As a result of changes to the central nervous system, dogs will gradually slow down mentally as they get older. Your dog may be less interested in what is going on around him (including less reactive), may spend more time sleeping and walk rather than run. In normal aging, a gradual decline in mental function can occur. 

Should your dog experience canine cognitive dysfunction, he may become disoriented, interact less with people or animals, experience disturbances in his sleep and become incontinent.

When your dog is aging, his brain will undergo certain changes at a molecular and cellular level. A significant cause of aging are free radicals, which are unstable oxygen molecules. These damage the cells and result in a loss of brain function in your dog. Your dog’s mitochondria will produce free radicals; as your dog ages, he will produce more free radicals and less energy, as opposed to when he was younger and would produce more energy and less free radicals.

Canine cognitive dysfunction syndrome is the result of beta amyloidal deposits in your dog’s brain. The proteins destroy nerves over time, which will lead to an accumulation of plaque in the brain that will hinder the transmission of the brain’s electrical signals.

Should you notice your dog having any of the symptoms noted above, or if he appears to be acting different than usual, it is best to schedule a visit with your veterinarian. Upon arriving for your appointment, your veterinarian will ask you for information regarding the symptoms and behavioral changes you have observed in your dog and when you first noticed them. Your veterinarian will conduct a full physical (including neurological) evaluation. 

Depending upon what is seen during the evaluation, along with the symptoms that you have described, your veterinarian may choose to conduct additional testing to help with diagnosis. This can include X-rays, MRI and CT scan, along with blood testing; in some cases, spinal fluid may be taken for analysis. Based on the test results, physical examination and the information you provide, your veterinarian will be able to make a diagnosis. 

In some cases, it may be recommended that you bring your dog to a neurologist, who will have had specialized training in diagnosing and treating brain aging. As there are treatments that can help alleviate the condition, the sooner your dog is diagnosed, the easier it will be to obtain effective treatment for him.

The cognitive decline associated with brain aging can be helped by nutrition and personal attention to your dog. Your veterinarian will recommend a diet that is high in antioxidants and fatty acids, as they can help fight the free radicals that are impacting your dog’s brain; studies show that this can alleviate symptoms within a few weeks. It will also be recommended that you keep your dog’s brain active, by providing a home with options for play and learning; for example you can hide treats in different places or use a dog treat puzzle toy. 

Additional activity may be recommended in order for your dog to develop strength; this additional activity will also help the brain and lead to improvement in your dog’s appetite, mood and sleep. With cognitive dysfunction, a monoamine oxidase inhibitor can be helpful. Anipryl is a recommended medication for dementia in dogs as it will increase the level of the dopamine, an essential neurotransmitter, in your dog’s brain. The overall treatment plan will depend on your dog’s condition, as some things can be controlled or managed, and progression can be slowed in others.

Your dog will benefit from attention paid to his nutrition and activity level from the time that he becomes a part of your life. Regular veterinary check-ups are helpful to ensure that any health conditions in your dog will be discovered and treatment begun before the condition worsens. As your dog ages, it is important to be observant and report to your veterinarian any changes that you notice in your dog. Once he begins showing signs of brain aging, it is important to follow the recommendations of your veterinarian in order to help your dog improve his brain function and overall quality of life.