Can Dogs Sense When You're About to Have a Seizure?

ByABC News
January 23, 2007, 5:28 PM

Jan, 25, 2007— -- Can well-trained service dogs sense an impending seizure in their epileptic masters?

Probably not, neurologists said in this week's issue of the journal Neurology. But even if dogs can't read our brainwaves per se, they still possess an almost uncanny ability to sense danger and protect their owners.

Seizure-alert dogs can sense and notify their human companions of an oncoming seizure. The notifying behavior would be anything markedly different from the dog's usual behavior, including close eye contact, circling, pawing or barking. This alerting behavior has been reported to show up anywhere from several seconds to 45 minutes or more before the onset of the seizure.

But a recent study suggests that the dogs don't sense the actual surge in electrical brain activity that usually characterizes a seizure -- so what do these dogs really pick up on?

Some epileptic owners of seizure-alerting dogs (SADs) have normal brain wave activity during convulsive events, according to the new report. This means the dog owner has "psychogenic non-epileptic seizures" (PNES) -- which is different from true epilepsy.

The same report recalled another seizure-alert dog that supposedly didn't so much predict his owner's seizures as cause them by licking the owner's face. Strange, but possibly true.

So, the seizure-sensing dogs that these researchers looked at weren't reacting to abnormal brain waves. Perhaps they detected a sound or odor to alert them to the impending danger.

It's not too much of a stretch of the imagination to believe that dogs, with their extraordinary sensory abilities, might be able to sense various impending events more quickly and more accurately than humans who are, by comparison, relatively insensitive.

Veterinarians often hear that dogs who are afraid of thunderstorms begin to pace and whine well before owners have the faintest notion that a storm is brewing. Dogs are also reported to be able to sense impending earthquakes, their owners' imminent return and their owners' emotional state.