To uncover these signs, researchers analyzed the behavior of 28 pet dogs aged between 10 and 16 years. The first signal highlighted by experts is that older dogs with dementia experience sleep problems. A study conducted by an international team of scientists revealed that dogs exhibiting symptoms of cognitive dysfunction (CCD) sleep less than what is typical for a healthy animal. Interestingly, this is one of the earliest signs of dementia in humans.
According to Dr. Natasha Olby from North Carolina State University, researchers have for the first time assessed cognitive impairments in dogs using polysomnography. This technique involves the overnight recording of physiological parameters of the sleeping subject through a specialized computer program.
What the Researchers Discovered
Similar to humans, dementia in dogs is directly linked to the aging process of the body, particularly the brain, leading to a decline in consciousness 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. These 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 so-called glymphatic system. This system is responsible for removing protein waste from the cerebrospinal fluid, the researcher 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.”
Interestingly, last year’s research indicated that 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 forgets about the bathroom, only to return home and “do its business” there.
- It increasingly disregards the house rules.
- The dog often appears anxious without any 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.