The Dog Who Was Afraid of Puddles
Autism, Epilepsy, and Rage
Fear is no more fun for dogs than it is for people.
—PATRICIA McCONNELL, PhD
Some animals are born with genetic tendencies to develop behavioral problems, and some animals have behaviors instilled into them by bad owners. The curse of an insensitive or preoccupied owner is terrible for any dog, but when an entire breed has genetic issues, even the best owner in the world can’t help. That’s where our work at Tufts comes in: we research the inherited behaviors of animals.
In the late 1980s, I found myself helping to run a dog-training class at the North Grafton Campus of Tufts University. Heading up the class was Brian Kilcommons, a dog trainer who was influenced by the legendary British expert Barbara Woodhouse and learned the core principles of his trade from master trainer the late Captain Arthur Haggerty. Out on a ball field on campus one day, he taught a group of dog owners how to properly control their pets on leash. At Brian’s request, I took over a bull terrier, named Blizzard, from its owner in order to demonstrate how to grasp the leash, how to walk without the dog pulling, how to do left and right turns.
Blizzard was a one-year-old white male. I noticed that, whenever we halted and I spoke with the owner, Blizzard would begin to lope lazily in circles, chasing his tail. I didn’t think much of it until the owner took me to one side at the end of the class. It turned out that he was a local bull terrier breeder, and he had a problem at his kennel. Several of his dogs chased their tails, just like Blizzard.
His story sounded familiar. By coincidence I had recently read a case report in the Journal of the American Veterinary Medical Association on tail chasing. The subject was also a white bull terrier, also a one-year-old male. The report might as well have been about Blizzard.
As the owner and I discussed the report, it suddenly hit me that the condition was most likely genetic, given that it had appeared in a dog almost identical to Blizzard. If only I could get my hands on a few more of these “bullies,” it would be a fantastic opportunity to get to the bottom of what was going on in the breed.
Back then, the explanation for tail chasing was that it was a stereotypy, a pointless, mindless behavior. Compulsive disorders hadn’t been suggested as a cause of these behaviors in dogs yet. Nonetheless, the tail chasing of bull terriers was different from that of other breeds. In bullies, it was associated with other bizarre behaviors, including strange phobias such as balking at rain puddles. It was also sometimes paired with a tendency toward explosive aggression. Because of these oddities, I was more inclined to think of tail chasing as a neurological, seizure-based condition, which few other scientists believed possible.
Two other cases that I came across in addition to Blizzard’s strengthened my opinion. One particularly severe tail chaser halted his schizoid behavior for only two reasons: to sleep when totally exhausted and to grab occasional mouthfuls of food. He spun so intensely and for so long that he wore the pads off his back feet and had to have his paws bandaged to prevent further damage. This dog was another white bully.
A large, Boston-based veterinary hospital referred the dog to me after a week of costly and exhaustive neurological testing. He arrived at my home in North Grafton on a Sunday afternoon.
I immediately administered an injection of Valium in an attempt to allow the dog some momentary peace. An antianxiety treatment for people, Valium is also a powerful anticonvulsant, and I wanted to explore the possibility that seizures were causing the bully’s distress. The drug is often used to treat status epilepticus in dogs, a very dangerous condition in which the brain experiences a constant state of seizure.
Within a few seconds of the injection, the bull terrier became totally calm, walking around my kitchen just like a normal dog. The sudden change in his behavior was close to miraculous. Unfortunately, Valium lasts only minutes in dogs and, twenty minutes later, the beleaguered guy began to lope around again in wide circles. Soon thereafter, he resumed his tail chasing at its previous frenetic level. The sad conclusion to this story is that the owners were so financially and emotionally drained that they could not pursue any of the treatment options I suggested, and the tormented dog was put down.
But this white bull terrier’s initial positive response to an anticonvulsant medication suggested that we could find a treatment for tail-chasing dogs. My colleagues and I eventually demonstrated that seizures are involved in the “bull terrier syndrome,” by performing EEG and CT scans of seven tail-chasing bull terriers and five unaffected “control” dogs. All seven tail-chasing bull terriers showed an epileptic brain-wave pattern. All but one of these dogs also had hydrocephalus, a structural abnormality often called “water on the brain.” Five of the seven tail-chasing dogs were successfully treated with that magical anticonvulsant, phenobarbital. Yet some veterinarians ignored our findings and continued to describe all tail chasing either as a stereotypy or compulsive disorder.
To better understand the breed, I collected more information about bull terriers. I also became friends with an outstanding bull terrier breeder and bully enthusiast, Marilyn Drews, who kept me well supplied with cases and information. In the course of our discussions, Marilyn sent me The Bull Terrier by E. S. Montgomery, a classic book published almost seventy years ago, as well as a children’s book called Boodil, My Dog.
The Bull Terrier is very hard to find, so it was a great treat to receive a copy. The book describes how bullies are derived from the bulldog, the English white terrier, and Dalmatians, as well as a few other breeds. Bull terriers are grouped as “white” or “colored,” which includes fawn, brindle and white, or black-and-white coat colors. Bullies have one of the highest prey drives of any breed. One champion bull terrier was said to have killed hundreds of rats in a single hour at a “sporting” pit in London. Citing examples of the behavior even way back in the late 1800s, the book sounded an early ominous note, observing that some bull terriers chased their tails.
Surprisingly and in its own way, the children’s book proved equally informative. The character of Boodil, a classic bull terrier, often acted the clown. She was obstinate and quirky, just like a real bull terrier. Boodil also spooked at puddles. She was afraid of the vacuum cleaner. And she froze underneath overhanging plants and bushes, a behavior known in the bull terrier world as “trancing.”
I became determined to understand—and to help cure—the tail chasing of bullies. Together with Dr. Alice Moon-Fanelli, PhD, a behavioral geneticist, we collected detailed behavioral information about affected dogs and healthy control subjects. We also took blood samples from as many dogs as possible for later DNA examination.
All together, Alice and I painstakingly analyzed the behavioral traits of a total of 333 dogs, slightly fewer than half of whom were tail chasers. We found that males were more likely to be affected than females, and that tail-chasing dogs also frequently displayed explosive aggression and trancing.
And then it hit me: The bullies could have a canine version of autism! This idea certainly jibed with all the significant signs and associations that we were otherwise struggling to explain. Sometimes in science, all the data in the world can’t prepare you for a eureka moment. You can’t plan to have one. Instead, lifelong training and experience suddenly will kick in, and the answer reveals itself. My eureka moment was exactly that—a moment—but it had taken a lifetime’s study of animals in order to get there.
Now we just had to prove it.
And before we could prove it, I needed to learn more about autism in humans.
Autistic children tend to have robotic movement disorders. Some rock back and forth. Others run in circles or flap their hands or spin in circles. Autism is more prevalent in boys, and it is associated with explosive aggression, trancelike staring behavior, repetitive movements, obsession with objects, and self-injurious behavior. Also, about a quarter of autistic people apparently suffer from full or partial seizures, which can take the form of unexplained staring spells, confusion, unexplained irritability, and aggressiveness.
Tail-chasing bull terriers also display these behaviors. Alice reminded me that many bull terrier owners described their dogs as “socially withdrawn.” Some had even asked her if their dogs could be autistic. A study of a large number of tail chasers confirmed that their owners regarded them as asocial and that they showed significant preoccupation with objects. It seemed like our case was halfway to being proved.
Dr. Ed Ginns had extracted and cataloged bull terrier DNA from our dogs even though neither he nor we had the facilities to analyze the samples. Fortunately, we were able to interest Dr. Elaine Ostrander, a branch chief at the National Institutes of Health and a world-renowned canine geneticist, in running our samples on a state-of-the-art Illumina “chip,” which maps gene sites on DNA and allows us to see where anomalies occur. It took months, but the results were worth waiting for: Affected bull terriers had a genetic anomaly on the X chromosome. That made sense, since with an X-linked problem, males can be more frequently affected than females. One well-known X-linked condition affecting people, for instance, Fragile X syndrome, is a genetic condition that causes intellectual disabilities. Fragile X is the most well-documented single-gene cause of autism.
Interestingly, people with Fragile X syndrome have large protruding ears, a long face, and a high-arched palate, as do bull terriers. Behavioral characteristics of Fragile X include movement disorders similar to those of bull terriers as well as atypical social development, particularly shyness and limited eye contact. Bullies seemed to have all the behavioral characteristics of Fragile X syndrome.
We really thought we were on to something, but further genetic testing proved our optimism to be premature. Reanalysis of the same data and whole genome genetic sequencing of two dogs—one severely affected and one not—failed to confirm our conclusions.
Such setbacks and dead ends crop up often in scientific research, especially in genetic testing. We just had to swallow hard and carry on, hoping eventually to discover the genetic cause of this obviously inherited condition. We went back to the drawing board and are currently reclassifying our dogs in degrees of severity and making sure that none of the control dogs had any hint of affliction, which may have interfered with the study.
In the meantime, a different way of studying the syndrome opened up to us. A medical expert at Tufts, Dr. Theoharides, who has been studying aspects of human autism for many years, was interested in what we’d discovered about bull terrier syndrome. Theo, as he is known, had demonstrated that autistic children have elevated serum levels of a peptide called neurotensin in their bloodstream. This was exactly the kind of biomarker we needed in order to make the connection between the human condition and the autism-like syndrome we’d found in the dogs.
We collected samples from affected and control bull terriers to measure neurotensin levels and sent them to Theo for analysis. A few weeks later he delivered the results: The average level in the affected bull terriers was significantly higher than the level in unaffected dogs. This could only mean one thing. Our tail-chasing dogs were almost certainly autistic.
News that Theo and our team at the veterinary school were studying a canine model of autism reached the Tufts University president, Dr. Anthony Monaco. In his research career, Dr. Monaco made his name working on the genetics of speech disorders and autism. Monaco and his team at Oxford University in England found that, in two families that they studied, glitches in a gene called cadherin-8 (CDH8) caused susceptibility to autism and learning disabilities.
We had found a different cadherin gene involved in our Dobermans with compulsive flank and blanket sucking, and a suggestion of involvement of yet another cadherin gene in the bull terriers, so we were particularly interested in his findings. After we finish detailed studies of these genes, we believe we can improve diagnosis of the canine condition and help develop new treatments for dogs and humans.
Dr. Theoharides and other experts have suggested that flavonoids may be helpful in controlling aberrant behavior of children with autism. These yellow crystalline plant phytonutrients are responsible for the rich color of fruits and vegetables. Flavonoids can act as “biological response modifiers.” Luteolin in particular, a flavonoid found in leaves, rinds, barks, clover blossoms, and ragweed pollen, has been demonstrated to have antioxidant, antiallergic, and anti-inflammatory properties. We plan to create a bull terrier study to evaluate the efficacy of luteolin for treating affected dogs.
A bull terrier aficionada in Britain, Terry Heath, removes additives, artificial colorings, and preservatives that are mixed into many foods that we and our dogs consume. When these artificial substances are excluded from a tail-chasing bull terrier’s diet, the condition improves markedly. Top psychiatrists agree that it can be helpful to remove these artificial substances from the diets of people with certain psychiatric disorders, including attention deficit hyperactivity disorder (ADHD) and possibly autism. So while autism may have genetic roots, environmental factors seem to play a role in the activation of autistic-like behaviors.
At the moment, however, the only available treatments we have are not cures but palliative drugs in the Prozac family, as well as NMDA-receptor blockers and anticonvulsants. The range of medications represents a motley crew of nonspecific, behavior-modifying therapies. They might help alleviate some behaviors but don’t treat the root cause, because we don’t know yet what that is.
If we were able to establish more clearly what is going on with tail-chasing bull terriers such as Blizzard, we could treat them more precisely and successfully. And any new therapies we develop might work in autistic children, too. Either way you cut it, it would be a clear win.
Seizures are often associated with autism. There are different kinds of seizures. They don’t necessarily have to be of the full grand-mal type, which involve the entire brain, and during which dogs might convulse, vocalize and salivate. Partial seizures, as mentioned previously, affect only a certain region of the brain. Depending on the brain region affected, partial seizures in humans, dogs, and cats can have varied expressions. The results of partial seizure activity are always distressing for the patient. In pets, they can disturb the owners, too. When the partial seizure triggers aggression, owners can find themselves in danger of being attacked.
Partial seizures can take the form of staring off into space (trancing), attacks of rage that seemingly come out of nowhere, or other bizarre expressions.
Like bull terriers, German shepherds are seizure-prone. And as we saw with Lief in chapter 5, German shepherds are prone to tail chasing. It is not uncommon to have a German shepherd suddenly develop grand mal seizures at around one to two years of age. But if a seizure were confined to a certain part of the brain, its manifestation could be tail chasing. Because the shepherd’s tail chasing is often classed as a compulsive behavior, it’s treated using anti-compulsive medication such as Prozac. But tail-chasing German shepherds do not respond well to this line of therapy. Typically, the improvement is rated at 20 percent or less. What does seem to work in many of these cases is adding an anticonvulsant into the mix. Because partial seizures manifest themselves in so many different ways, and can originate in so many different parts of the brain (hence the term “partial”), recognizing and treating them is challenging. I’ve encountered dogs who variously get intense rage, experience nighttime aggression, show practically paralyzing fear, chase their tails, stare at the sky, smack their lips, snap at imaginary flies, and gulp in air. I found support for my treatment of partial seizures from a study of dogs with a bizarre EEG pattern that was improved by anticonvulsants. One of the dogs displayed fly-snapping behavior.
Tail chasing and fly snapping are probably triggered deep within the brain, in a region called the hypothalamus. In humans, the hypothalamus serves multiple functions, including the regulation of sexual behavior, appetite, and emotions. In dogs, this brain region facilitates the same functions, including the appetitive phase of predatory behavior. This is why partial seizure activity in the brain region likely causes predatory-type responses, such as tail chasing and fly snapping, in dogs. These happen more commonly in dogs with high prey drive, such as terriers and herding breeds. The reason may be simply that brains of those breeds are wired in a way that makes them susceptible to seizure activity of a predatory type.
Laboratory experiments with cats have demonstrated the involvement of the hypothalamus in predatory behavior. Researchers put rats into cages with cats who remained passive and did not spontaneously attack the rats. But when the scientists activated electrodes that had been implanted in the cats’ hypothalamus, the previously mild-mannered cats suddenly turned predatory and attacked the rats.
The hypothalamus is only one of several parts of the brain where seizures can occur. A few years ago I got to know a white female bull terrier called Stella, who entered my office one morning as if she were walking on eggshells. Her tentative slow-motion gait resembled the dance step called moonwalking.
Stella’s overall behavior revealed that she lived in abject fear. Her extreme fright over almost everything meant that she didn’t have much of a life. She had become a recluse, would not play with the other dogs in the home and could not even leave the house. During the consultation, I accidentally dropped a manila file. Stella jumped almost out of her skin.
I had never seen such extreme fear and reactions in a dog. There was no apparent reason for it. Stella’s history was unremarkable. She had been well socialized and had never been abused. Other environmental factors were discounted, one after another. Poor Stella. I felt so bad for this craven, frightened dog.
The usual explanations for fear didn’t fit her condition. After running through and discarding possible diagnoses, I fixed once again on complex partial seizures. But this time I considered that perhaps Stella’s seizures originated not in the hypothalamus, like the enraged or tail-chasing dogs, but rather in the amygdala, or the “fear center” of the brain. An ongoing aberrant electrical discharge in this region might present as extreme fear. I ran an EEG. Sure enough, the results showed abnormal epileptic-like activity. I immediately started Stella on a treatment with phenobarbital.
The outcome was nothing short of spectacular. Within days Stella was a different dog, running with the other dogs in the back garden, playing a game of “king of the hill” on a mound of dirt. She generally behaved like a normal canine. Her fear was gone. Stella got her life back or, to put it in terms of a recent movie title, got her groove back. She later became somewhat tolerant of the medication, which is common, and some of her fearful behavior returned. But she remained about 70 percent improved.
As I treated more dogs with symptoms of partial seizures, I found more, unexpected triggers for them. For instance, sunlight can set them off. Benny, a seven-year-old spayed female German shepherd cross, was afraid of sunlight as well as flashing lights. Benny’s owner showed me a heartbreaking home movie of Benny on the back porch, glancing anxiously at the sun, shivering with fear, and salivating profusely.
Benny’s history was complex. She had been hit by a car and afterward developed bouts of chewing objects, salivating, and hiccuping. The local vet diagnosed the chewing and hiccuping as trauma-induced seizures, and treated Benny with phenobarbital. The chewing and hiccuping decreased in frequency but did not entirely stop. I reckoned that Benny’s fear of sunlight might be attributable to partial seizure activity, too.
But how could we treat her? A change in dose of the anticonvulsant, or the addition of other drugs, might make her life more bearable, so we tweaked the phenobarbital dose and added another anticonvulsant, potassium bromide, to her regimen. And, for what the owner termed “bad Benny days,” when the sun was particularly bright, he could also give her a Valium-type drug, so that Benny had a little something extra to ease her troubled mind.
She responded well to the treatments. Eventually, Benny could tolerate light in all its forms much better than she had since being hit by the car.
Bernie, a beautiful Bernese mountain dog, was brought to me because he had begun to stargaze, fly-snap, and lick and smack his lips at the age of two. Like Stella, he was also incredibly fearful, forever bolting terrified from room to room, glancing continually over his shoulder.
All these behaviors have been reported in people suffering from partial seizures. An EEG showed an epileptic-like pattern in Bernie’s brain waves. This time, though, instead of the old standby, phenobarbital, we went with an herb, huperzine, which has anticonvulsant properties. It practically eliminated the problem.
I had been searching for an alternative treatment because of the disturbing side effects of phenobarbital, which include extreme thirst, excessive urination, increased appetite, weight gain, and, worst of all, liver damage. I’d heard about huperzine, an extract of Chinese club moss (Huperzia serrata), through a friend and colleague, Dr. Steve Schachter, professor of neurology at Harvard’s Beth Israel Hospital. An expert on epilepsy, Steve had learned that huperzine was being used in cases of Huntington’s disease, a genetic disorder that is frequently associated with seizures. After he had found that an extract of the herb was effective at preventing seizures in mice, he suggested we see if it could help dogs. We don’t often employ herbal extracts at Tufts, but with Steve’s glowing report of its efficacy and safety in dogs, we were confident we would have a productive and safe trial.
In fact, Bernie was one of the first of a series of dogs we treated successfully with huperzine, and he enjoyed freedom from his seizures for about six months. But, sadly, that wasn’t the end of his trials. Bernie began showing signs of arthritic pain, even though he was still a young dog. This is a fairly common problem in large breeds such as Bernese mountain dogs. His local veterinarian prescribed a painkiller, tramadol. Unfortunately, tramadol can bring on seizures, and Bernie’s stargazing, fly snapping, and strange lip behavior immediately returned. To get him back under control we reverted to phenobarbital, which helped markedly reduce all the behaviors he’d had from the seizures.
Of course, we hope that our series of successes in reducing seizures with huperzine will inspire a pharmaceutical company to develop it into an approved remedy for human cases of epilepsy. It’s always gratifying to be able to give peace to an animal who has been suffering from unpleasant, disabling seizures. We’ve really given the dogs their lives back, and enabled them to interact with the people who love them.
After I’d treated dozens of dogs who exhibited partial seizures, a couple brought their four-year-old, intact female spaniel to see me. They announced at the beginning of the appointment that the spaniel was a “glugger.” That was a term that I had never heard used before, which made sense because the owners themselves had coined it. The dog would gulp and swallow over and over. She would also air-lick, happily ingest dust bunnies and other debris, and sometimes lick or chew the linoleum floor covering.
Out in the yard, the dog would scarf down grass and dirt, sometimes throwing it straight back up. Then, as if a light switch had been thrown, her behavior would return to normal. These bouts of aberrant behavior had begun when she was one and a half years old. They occurred regularly thereafter.
When I asked the couple how long the attacks lasted, one said “minutes” and the other “hours.” It turns out they were both right. When the dog was in this behavioral warp, individual glugging bouts lasted only a couple of minutes. But each attack was linked together with others in clusters, so a collection of bouts could last several hours. As in people with partial seizures, the aftermath can leave an animal exhausted, unreactive, or even fearful and aggressive. This so-called postictal period is one of the hallmarks of partial seizures, and it is used to help confirm the diagnosis. But the spaniel never displayed any confusion or sleepiness after these events. For the little spaniel, the seizures at the root of her problem might well be in the lateral hypothalamus, which controls feeding impulses and eating behavior as well as predatory behavior. The owners preferred that we not run an EEG on their dog to find out for sure if the brain waves showed a pattern of seizures, but they were happy to try her on phenobarbital to see if that helped her. And in fact, the dog’s glugging episodes faded over a few weeks of starting the phenobarbital and never recurred. A full two years later the dog was still on phenobarbital and was still glug free. And the phenobarbital had not sedated her, as it can some dogs, so that was not the reason for her improvement.
Another pair of owners whose dog also swallowed oddly told me that their dog was a “snoofer.” When I showed them the video of the glugger, they said, “Yes, that’s it!” I treated that dog with phenobarbital, too, with the same great results. Interestingly, the snoofer, though not usually aggressive, became so immediately following a snoofing episode. This aggression after the seizure-caused “snoofing” could have been the result of miniature electrical aftershocks radiating out from one part of the brain. Signals emanating from the lateral hypothalamus, which controls eating behavior, could have been affecting a different part, the medial hypothalamus, which is involved in propagating rage.
Many dogs who suffer from grand mal seizures show aggression after the seizures subside. After I published the case of the glugger and the snoofer in the Journal of the American Veterinary Medical Association, I was immediately inundated with scores of owners around the country who reported that their dogs, too, glugged or snoofed.
Some people with partial seizures at times swallow rapidly at the beginning of an attack, and may also smack or lick their lips and work their jaws as if chewing. They feel queasy and become light-headed. They do not necessarily become unconscious, as people who suffer grand mal seizures often do, but they may experience a blurred concept of reality, during which they may exhibit violent episodes of uncontrollable rage and destructive behavior, after minimal or no apparent provocation. This condition, known as episodic dyscontrol, occurs in dogs, too. Yet as in the glugging spaniel, some people may come out of mini-seizure attacks with no apparent confusion, sleepiness, or ugly mood.
Cats can be affected by partial seizures, too. They can go through the “rage” that dogs show and the “episodic dyscontrol” that people show. These cats can also have occasional, unpredictable bouts of severe aggression toward people, usually their owners.
One cat flew off the handle one night when his owner came into the house from the deck. The attack was extremely violent, and the poor owner had to escape and spend the night elsewhere until her beloved pet calmed down. On another occasion, the same cat wouldn’t let the owner into the kitchen, even to let her feed him or refill the water bowl. The attacks were random and very violent. This behavior sounded to me like the result of partial seizures and so we treated him with an anticonvulsant. After spending a few days in our hospital, the cat became supercalm—and he was never again aggressive.
I have seen several similar cases since. My most recent angry cat was named Lillian. One day, out of the blue, she attacked her owner, Michael, while he was sitting on the couch. Lillian had always been mellow and affectionate, but her meltdown was so severe and long-lasting that Michael was afraid that he might have to put her down.
To avoid that sad end, I volunteered to keep Lillian in my wife’s practice area, downstairs at our home, until a course of phenobarbital kicked in. To be honest, Lillian was quite a handful at the time. We had to treat her with great caution so that we were not bitten, and for a few days we would interact with her only when necessary. But once again, the treatment worked like a dream and Lillian was able to return to Michael as her old affectionate self. She continues to do well to this day on the anticonvulsant.
Another feline manifestation of partial seizures is known as feline hyperesthesia syndrome (FHS). FHS is a strange episodic condition in which a cat’s pupils dilate, its skin ripples as if it’s trying to shake off flies, and it grooms itself frenetically along the spine. Cats with FHS may also show scary levels of aggression when in this state. Some dash away from unseen enemies. Others bite their tails until they’re bloody. They also seem to hallucinate, staring off into space and then ducking as if being dive-bombed.
Some vets have suggested that FHS may be the feline equivalent of schizophrenia and have proposed treatment with antipsychotic medication. Others dismiss it as nothing more than a manifestation of muscle pain or discomfort along the cat’s spine. Yet others think of FHS as a feline compulsive disorder. Some cats do indeed respond well to anti-obsessional drugs such as Prozac, but Prozac has some anticonvulsant properties at certain doses, so the story may be more complicated than “simply” a compulsive disorder.
I believe complex partial seizure activity is the root cause of FHS. Cats with FHS respond well to classic anticonvulsant drugs. Years ago, a Siamese cat called Spike was brought to me because he was chasing and attacking his tail. Spike was already being treated by his local vet with phenobarbital for grand mal epilepsy, specifically because he was prone to severe convulsive seizures. The tail biting was the last vestige of the strange FHS condition, so I prescribed a Prozac-like antidepressant to try to alleviate that final symptom. Fortunately it did the trick, and Spike and his tail greatly improved.
People who have frontal lobe seizures can also have extreme and involuntary self-injurious behavior, like head banging, skin gouging, and self-biting. Children with seizures may obsessively groom their hair. People in the middle of a partial seizure often have enlarged pupils and experience a feeling of dread and fear. They may run mindlessly. Some have “out-of-body experiences” and visions or hallucinations. Because the symptoms of human cases of partial seizures so closely resemble those of animals, they support my diagnoses of partial seizures in pets.
But for further validation, I turned once again to my neurologist friend, Dr. Steve Schachter, the epilepsy expert. We’d run a lot of EEGs on dogs, for which they had to be lightly anesthetized so they’d remain still enough for the test. I was a little concerned that the results of the test may have been skewed by the effects of the sedation. By contrast, human patients remain fully conscious during an EEG and are fitted with a skullcap that has electrodes implanted in it to sense the brain’s electrical signals, which are then transmitted to a recorder. Special filters are used in the analysis to remove electrical signals that merely show the movement of muscles due to consciousness, leaving the brain-wave activity plain to see.
I wanted to try to get EEGs of my dog patients while they were awake, and invited Dr. Schachter to the veterinary school to see if we could pull it off with a dog or two. Our first patient was a tail-chasing bull terrier, who had shown some scary aggression toward anyone who approached him. Dr. Schachter, it turns out, is fearless. Steve did not hesitate to kneel down on the consulting room floor and apply various needle electrodes to the dog’s scalp. The dog lunged and snapped at him, but Steve was unfazed.
Steve recorded this dog’s EEG for several minutes and the report showed a reasonable tracing of activity. The results were not quite conclusive enough for us to make a definitive diagnosis, but at least we had made a start. More importantly, Steve still had all his fingers.
People with epilepsy often show abnormal brain-wave activity between seizures, “spikes” and “sharp waves.” These small bursts of electrical activity cause the release of minuscule amounts of neurochemicals in whichever brain region they occur, which affect the patient in various ways. For example, if the mini-events occurred in a region of the brain’s emotional center, the limbic system, the subject’s moods can be affected in subtle, persistent ways, causing fear and anxiety. This spiking could account for the persistent fear I’d seen in some of my animal patients.
Dr. Schachter wrote a book, Brainstorms: Epilepsy in Our Words, which collects the experiences of many of his patients. Some patients report anger as a trigger for their seizures, which brings to mind the springer spaniels and other breeds prone to rage. In almost 10 percent of Dr. Schachter’s cases, intense fear heralds the onset of a seizure, which recalls Stella and her moonwalking. Other human subjects are like Benny, the light-sensitive German shepherd cross, and find that flickering sunlight triggers an attack of spontaneous swallowing. Some spin in tight circles, as do tail-chasing bull terriers. In both humans and dogs, sleep can be a trigger for seizures. Dogs we have treated take a while to return to normal following their partial seizures and one of Dr. Schachter’s patients reported that even twelve hours after a seizure she still had a hard time talking. Sometimes full recovery can take as long as four to five days.
Through our research over the years, we’ve been able to relieve the suffering of hundreds of pets. Today, when I’m confronted with a tail-chasing dog or cat, I feel myself to be on a lot firmer footing than I was in the days before we could give animals EEGs and logically employ anticonvulsant medications developed for people.