The study was published in the journal Scientific Reports and conducted by researchers from the University of Rennes in France.
According to the researchers, dogs can distinguish a telltale scent connected with epileptic seizures. This suggests that dogs can be trained to warn owners before they experience a seizure.
The results also help explain anecdotal reports wherein owners believe their dogs have sensed that they were about to have a seizure.
The researchers are hopeful about the results because knowing when a seizure is about to occur can give individuals with epilepsy greater control and independence. With a warning from their dogs, people can take precautions to prevent injuries, take medication to manage their condition, or seek help.
Amelie Catala, the study's first author, explained that even though there are reports of pet owners who claim that their dogs have alerted them before a seizure, there wasn't any strong evidence in the scientific literature. She added that in these cases, it was unclear if the dogs relied on visual cues or subtle changes in behavior or smell, and whether the cues were the same for all individuals with epilepsy.
In the study, the researchers wanted to determine if five specially trained dogs could distinguish breath and body odor samples taken from patients with epilepsy during a seizure from samples taken during normal conditions and after an exercise session.
The dogs were selected by Medical Mutts from shelters to be trained by professional trainers as service dogs. Dogs were chosen based on criteria such as temperament traits compatible with service dog training and physical aptitudes.
Before the testing sessions, the dogs were trained to identify seizure samples. The trained dogs were then tested using samples taken from five participants with different forms of epilepsy.
The dogs’ ability to detect positives ranged from 67 percent to 100 percent and their ability to correctly identify negatives ranged from 95 percent to 100 percent.
The test results hinted that regardless of the type of seizure or the background body odor of a patient, seizures are linked to specific odors. (Related: Scientists STUNNED: Dogs are able to detect cancer more accurately than many laboratories.)
A representative for the charity Epilepsy Action shared that some individuals already depend on their dogs to predict seizures. She added that since it is yet to be determined if dogs predict seizures using their sense of smell or some other sense, the research is interesting. The findings could be used to determine how dogs can help individuals who have uncontrolled epilepsy.
Rita Howson, the chief executive of Support Dogs, a charity that trains dogs to help individuals diagnosed with autism, epilepsy, and other conditions, said that dogs are “very good observers of humans.”
Howson shared that the behavior of dogs suggest that they know what's about to happen once owners pick up their leash. The behavior of dogs can also change once they pick up on subtler cues, like a smell or behavioral change in owners that occurs before a seizure takes place.
The researchers plan to conduct further studies to determine if this telltale odor preceded the seizure and if dogs can be trained to effectively alert owners before their seizures occur.