How do you determine when a dog has Canine Cognitive Dysfunction Syndrome (CCDS), sometimes called “doggy dementia”?

For families with an aging dog, the question is deeply personal. Subtle changes, such as disorientation, disrupted sleep, house soiling, and clinging more to you, can be heartbreaking and worrisome.Is this simply normal aging? Or is it something more?

In human medicine, Alzheimer’s disease is diagnosed through a multi-layered process that spans physical and neurological exams, cognitive testing, advanced imaging, and biomarkers that detect disease-specific proteins. Over the past 15 years, a shared, modern framework defining Alzheimer’s disease stages has enabled earlier and more accurate diagnoses, sparked collaboration, improved care, and opened new pathways for research.

In dogs, the story has been very different.

Until recently, veterinarians had no consensus guidelines for diagnosing CCDS, meaning diagnoses could vary widely based on individual experience. Clinicians lacked reliable tools to tell normal aging apart from true cognitive decline. Without standardized criteria, research into age-related cognitive changes in dogs has lagged behind human medicine—not because CCDS is rare, but because a solid scientific framework for studying it systematically was missing.

That is now beginning to change.