In this article

1. Six patterns worth describing
2. Check for other explanations first
3. What “common but underdiagnosed” actually means
4. Activity is associated with better cognition, with limits
5. Enrichment is care, not a promise of a cure
6. Build a familiar, forgiving home routine

Perhaps your older dog stands at the wrong side of a familiar door, wanders after bedtime or seems less sure of people they know. Cognitive dysfunction, often called doggy dementia, can cause changes in memory, sleep and behaviour. PDSA recommends a veterinary appointment when you notice these changes, rather than putting them down to age¹.

It can feel disloyal to mention that a beloved dog is behaving differently. You are describing what they need, not criticising them. Bring the small observations as well as the difficult nights; you do not need a settled explanation before asking for help.

Six patterns worth describing

Veterinary teams often organise cognitive signs using DISHAA: disorientation, changed interactions, sleep changes, house soiling, altered activity and anxiety. The American Animal Hospital Association describes night-time restlessness, reduced interaction and confusion at home among common signs. The categories help organise a history; they do not establish the diagnosis².

Pattern	An everyday example to mention
Disorientation	Appearing lost in a familiar room2.
Interactions	Greeting or seeking company differently2.
Sleep	Sleeping by day and becoming restless at night2.
House soiling	Accidents after reliable toilet training2.
Activity	Repetitive pacing or less purposeful activity2.
Anxiety	New distress around previously familiar situations2.

Use examples rather than labels. “He stood behind the chair until I helped him out” tells the team something different from “He is getting old.” Note whether a behaviour is new, more frequent or happening in a different situation. Your account can be brief and still be useful.

Check for other explanations first

A 2026 clinical review stresses that cognitive dysfunction is a diagnosis reached after considering other causes. Pain, declining sight or hearing, hormone disorders, organ disease and problems within the brain can produce overlapping signs. An older dog may also have more than one condition contributing to what you see³.

The review describes a history, physical and neurological examination, with blood and urine testing and further investigations selected according to the case. A questionnaire can help describe and monitor behaviour, but it cannot separate all these possibilities by itself. Ask what each proposed investigation is intended to clarify³.

If confusion begins suddenly or comes with unusual neurological signs, tell the practice promptly rather than assuming gradual cognitive decline. The review identifies an acute onset or focal neurological abnormalities as particular reasons to investigate other brain disease. Describe the timing as clearly as the behaviour³.

For the appointment, make a short account of an ordinary day: meals, walks, sleep, toileting and time spent with people. Add current medicines and the question that is worrying you most. If night waking is the hardest part, say so; that deserves space in the consultation.

What “common but underdiagnosed” actually means

An influential survey published in 2010 estimated cognitive dysfunction in 14.2% of the older dogs analysed, using behaviour-based criteria. Only 1.9% of that same analysed group had a reported veterinary diagnosis. These percentages share the whole-group denominator; the finding does not mean only 1.9% of affected dogs were diagnosed⁴.

This was a community survey with responses from several countries, largely Australia and the United States. Owners reported other illnesses, and dogs did not all undergo examinations to exclude alternative explanations. Its estimate should therefore not be treated as the proportion of every UK senior dog population affected today⁴.

The important household question remains individual: what has changed for your dog? A population estimate cannot decide whether a particular night's pacing is due to pain, confusion, a need to toilet or something else. Take the observation to the practice without needing the statistic to prove that it matters.

Activity is associated with better cognition, with limits

The Dog Aging Project examined owner questionnaires for 15,019 US dogs in a study published in 2022. After adjustment for other measured characteristics, the odds of meeting its cognitive dysfunction threshold increased by 52% with each additional year of age. Less active dogs also had higher odds than very active dogs⁵.

These were observations at baseline, not a trial assigning dogs different exercise programmes. The researchers explicitly note that cognitive decline itself might reduce activity, and unmeasured factors could contribute. The result does not show that increasing a dog's walking distance will prevent dementia or reverse established disease⁵.

Owner reporting and the questionnaire threshold bring further uncertainty. Sensory problems may affect answers about finding food or bumping into objects. These limitations make the study useful for asking better questions, rather than prescribing an exercise target from its odds ratios⁵.

Keep the next step modest and specific. Ask what kind of activity is comfortable for your dog, which signs should end a session and what to do on a difficult day. An agreed plan is easier to use than a household debate about whether the dog has done enough.

Enrichment is care, not a promise of a cure

A two-year study in older laboratory Beagles tested an enriched activity programme and an antioxidant-fortified diet. Learning outcomes were better with enrichment and some improved with dietary fortification; the combined group generally performed best. This provides experimental support for studying how environment and nutrition affect cognitive ageing⁶.

The published abstract describes learning tasks in a research population, rather than a cure trial in household dogs with diagnosed dementia. Its findings cannot establish that a shop-bought supplement or a particular puzzle will produce the same benefit for your dog. Discuss dietary changes with the vet as part of the wider plan⁶.

AAHA's guidance similarly describes the evidence for many supplements and other proposed therapies as limited. It supports a broader management approach and taking anxiety seriously, including consideration of pain. Ask which outcome a treatment is meant to improve and when the team expects to review it².

There is room here for familiar pleasures without turning every interaction into a test. A shared moment can simply be enjoyable. You do not need to keep increasing difficulty, count successful answers or compare today with the dog your companion was several years ago.

Build a familiar, forgiving home routine

Cornell's senior-dog guidance recommends predictable routines, keeping beds and bowls in familiar positions and blocking unsafe spaces such as stairs or gaps behind furniture. Nightlights can help dogs navigating after dark. Match games and scent activities to the dog's physical ability, and respect whether they want company or quiet⁷.

For new toilet accidents, Cornell recommends checking for causes such as bladder infection before assuming dementia. Extra opportunities to go outside may help management. Arrange the practical details with the household so the dog does not have to wait while everyone assumes someone else has already taken them⁷.

PDSA recommends gentle activities, simple reward-based training and patience with forgotten skills. It also advises a discussion about quality of life as the condition progresses. Treatment and home management may help for some time, but there is currently no cure and the plan needs to change with the dog¹.

Include your own capacity in that conversation. You can love your dog deeply and still be exhausted by repeated broken nights. A realistic plan leaves you knowing what to try, who will help and when to reassess comfort together, with the dog's daily experience at its centre.

Sources and further reading7 sources

The small numbers in the article link to the source behind each fact. Sources open on their own websites.

1. Dementia in dogs: cognitive dysfunctionPDSA
2. Managing Cognitive Dysfunction and Behavioral AnxietyAmerican Animal Hospital Association
3. Evidence-Based Clinical Management of Canine Cognitive Dysfunction Syndrome: Diagnostic Algorithms, Practical Guidelines …Animals
4. Under diagnosis of canine cognitive dysfunction: A cross-sectional survey of older companion dogsThe Veterinary Journal
5. Evaluation of cognitive function in the Dog Aging Project: associations with baseline canine characteristicsScientific Reports
6. Learning ability in aged beagle dogs is preserved by behavioral enrichment and dietary fortification: a two-year longitudinal studyNeurobiology of Aging
7. Senior dog dementiaCornell University College of Veterinary Medicine