Gaby
Researchers analyzed 28 pet dogs, ages 10 to 16, to uncover telltale signs of dementia. The first red flag they identified was sleep problems in older dogs with dementia. An international study found that dogs showing symptoms of canine cognitive dysfunction (CCD) sleep less than healthy dogs. This mirrors human dementia, where sleep changes are also one of the earliest signs.
Dr. Natasha Olby of North Carolina State University says researchers used polysomnography to assess cognitive impairments in dogs for the first time. Polysomnography records physiological signals overnight—eye movements, heart rate, and muscle activity—using specialized equipment.
What the Researchers Discovered
Like humans, dementia in dogs is linked to aging, especially changes in the brain, and leads to declines in cognition and memory. At the beginning of the study, the scientists asked pet owners to report on their animals’ health, including any potential symptoms of CCD. Those symptoms included avoidance of social interactions, disorientation, and anxiety, as reported by the Daily Mail.
The dogs were then taken to a sleep clinic, where the team analyzed their eye movements, heart rate, and muscle activity using polysomnography. All but two of the dogs entered a state of drowsiness. Subsequently, 24 of the animals transitioned into a phase known as slow-wave sleep, characterized by reduced brain activity. More than half of the group then entered the rapid eye movement (REM) sleep phase, which is marked by heightened brain activity and dreaming.
According to the study’s findings, 28.5% of the dogs exhibited severe forms of dementia, while 14.3% suffered from moderate dementia, and 28.5% had mild forms. The remaining participants showed no symptoms of CCD. Natasha Olby noted that slow brain waves in humans, typical of the slow-wave sleep phase, are associated with the activity of the glymphatic system. This system removes protein waste from the brain via cerebrospinal fluid, she explained. She added that “the reduction of slow waves in people with Alzheimer’s disease and insufficient removal of these toxins is linked to poor memory consolidation during deep sleep.”
Last year’s research indicated the risk of canine dementia increases by 52% each year after a dog turns 10. Inactive animals are 6.5 times more likely to develop canine dementia compared to those that engage in regular exercise.
Signs of Dementia Development in Dogs
- The dog forgets family members.
- It no longer remembers familiar walking routes.
- The dog forgets to ask to go outside to relieve itself.
- It may go outside but forget the reason for going out and then return home and relieve itself indoors.
- It increasingly disregards the house rules.
- The dog often appears anxious for no visible reason.
- It does not greet its owner when they return home.
- The dog shows less interest in play than before and is generally less active.
- It takes longer to learn new tasks.
- The dog sleeps during the day instead of at night.
