The RVC’s canine epilepsy research team, after conducting a series of studies concerned with cognitive impairment in dogs with epilepsy, has distilled four key findings from the research.   

The researchers combined a range of techniques, including an epidemiological study of more than 4,000 dogs, measuring trainability and signs usually associated with canine dementia, problem solving and spatial memory tasks, to assess the cognitive function of affected dogs.

The pioneering studies revealed the following key findings, which have ramifications for canine welfare, veterinary treatment, owner awareness, dog training and future research:

• Dogs with epilepsy find it harder to obey commands, are slower to learn tricks, have spatial memory deficits and are more easily distracted.
• Aversive training methods, such as bark-activated collars, prong collars and verbal punishment are associated with poorer trainability and their use should be avoided.
• Some anti-epileptic drugs were found to worsen the cognitive impairment of dogs with epilepsy.
• Dogs with greater exposure to positive training activities were more trainable and had fewer signs of cognitive dysfunction. 

Epilepsy is the most common chronic neurological disorder found in dogs and humans, with 1 in 111 of the population being affected. Epilepsy is characterised by recurrent seizures, but in human patients it is also often accompanied with cognitive deficits, for example impairments in learning and memory. Research into canines is increasingly finding similarities between epilepsy in dogs and humans, but there has not been the same focus on the cognitive abilities of affected dogs. The RVC studies sought to redress that.

The RVC team found that dogs with epilepsy were less trainable than control dogs¹. Dogs with epilepsy found it harder to obey a sit or stay command, were slower to learn tricks, were more easily distracted by interesting sights, sounds or smells, and less likely to pay attention to owners. Furthermore, anti-epileptic drugs were found to worsen behaviour abnormalities, particularly the medications potassium bromide and zonisamide, along with the use of multiple drugs simultaneously.
In a second study, dogs with epilepsy were found to show more signs of cognitive dysfunction (‘canine dementia’) than control dogs². Dogs with epilepsy more commonly failed to recognise familiar people, had difficulty finding food dropped on the floor, and paced or wandered without purpose.

These signs were seen in dogs under four years of age, and thus are unlikely to represent classic canine dementia seen in geriatric dogs. Those dogs with a history of cluster seizures or a high seizure frequency were most likely to show these signs, which may reflect progressive brain damage from recurrent seizures.

In the third study³, using a task developed to measure signs of cognitive dysfunction in a clinical setting, epileptic dogs were found to show reduced performance in a spatial memory task than matched controls. While most control dogs were able to immediately find a food reward in a room after a short period of ‘forgetting time’, dogs with epilepsy spent longer searching for the reward.

Commenting on the ramifications of the studies, Dr Rowena Packer, BBSRC Research Fellow at the RVC, said: “Our findings have practical implications for canine welfare, as well as helping to strengthen the comparison model between dogs and humans. Although some dogs with epilepsy may appear to be ‘naughty’ to their owners, we would urge all owners to avoid using harsh, aversive training methods with their dogs, instead we would recommend using reward-based methods such as food rewards or verbal praise.”

Professor Holger Volk, Head of Department Clinical Science and Services, added: “We increasingly recognise that epilepsy in dogs is far more than a simple seizure disorder. We have learned that apart from seizures and anti-epileptic drug side effects, there are multiple behavioural and cognitive changes in epileptic dogs which could also impact their quality of life. There is an urgent need to expand our understanding of the complex interplay of these factors, so that we can develop better precision medicine approaches. A more holistic and at the same time individually tailored management of epileptic canine patients is needed.”

Cited papers

1) Packer RMA; McGreevy PD; Pergande A; Volk HA (2018) Negative effects of epilepsy and anti-epileptic drugs on the trainability of dogs with naturally occurring idiopathic epilepsy. Applied Animal Behaviour Science 200: 106-113.

2) Packer RMA; McGreevy PD; Salvin HA; Valenzuela M; Chaplin C; Volk HA (2018) Cognitive dysfunction in naturally occurring canine idiopathic epilepsy. PLoS ONE 13(2): e0192182.

3) Winter J; Packer RMA; Volk HA (2018) A preliminary assessment of cognitive impairments in canine idiopathic epilepsy. Veterinary Record 10.1136/vr.104603.