Emotional remove, repetitive (sometimes self-injurious) behaviors, unexplained and often aggressive outbursts, trance-like staring. These are some of the hallmarks of autism, a disorder currently identified in one in 59 children, according to estimates by the Centers for Disease Control and Prevention.
Concerns about autism in the general public have grown not only because of the increase in diagnoses but also because of a widely publicized study published in 1998 in the British medical journal The Lancet. It linked the childhood MMR vaccine for measles, mumps, and rubella to a loss of social and cognitive skills and developmental regression in young children. That is, it looked like the vaccine intended to protect children was making them autistic.
The study was retracted by the journal seven years ago. It had been based on a very small sample of a dozen children, none of whom were chosen randomly. And a portion of the study’s funding came from the lawyers of parents of some of the children in the study who intended to sue the vaccine manufacturers. The results were far from arm’s length.
Still, the facts often lag behind the chatter, so much so that the Head of the Tufts Animal Behavior Clinic, Stephanie Borns-Weil, DVM, has heard concerns from clients about an autism-vaccine link in their dogs, as well as concerns connecting canine vaccines to various other neurological or behavioral problems. Could there be something there?
No. “There is no evidence at all that vaccines in any species cause autism,” the doctor says. The original data on children, she adds, were not scientifically valid and have never been replicated. The lead author of the so-called research has since lost his medical license.
Still, can a dog be autistic? Clients do sometimes bring their dogs to Dr. Borns-Weil specifically to discuss behaviors that make them wonder about autism — aloofness, repetitive behaviors, and outbursts, to name a few. And in the field of comparative medicine, new findings suggest that we and our canine friends share some of the same genetic propensities for illnesses similar to autism.
Some tantalizing facts on the ground (and in the body)
Tufts Cummings School of Veterinary Medicine Professor Emeritus Nicholas Dodman, BVMS, who headed our Animal Behavior Clinic prior to retirement, has a chapter in his compelling book, Pets on the Couch, that looks specifically at whether dogs can have autism. In it, he details his research and observations concerning bull terriers, who are prone to the repetitive behavior of tail chasing. A number of breeds chase their own tails, often to the point of pure exhaustion, and even madness. Their compulsivity gets the better of them.
But it’s different in bull terriers, Dr. Dodman says, because it’s associated with other bizarre behaviors, including strange phobias (of rain puddles, for instance) and a tendency toward explosive aggression. Some bull terriers also engage in what Dr. Dodman calls “trancing” — freezing and kind of staring at nothing. When he and his then-Tufts colleague, Alice Moon-Fanelli, PhD, painstakingly analyzed the behavioral traits of 333 dogs, they found that the tail chasers among them (slightly fewer than half of the study cohort) were more likely to be male and more likely to engage in the other unusual behaviors. Many bull terrier owners also describe their dogs as socially withdrawn.
Autistic people, too, are more likely to be male than female and can have unusual movements — rocking back and forth, for instance, or flapping their hands (stimming) or spinning in circles. They can have trance-like staring behavior also, along with explosive aggression.
It’s not just the similarity in behavior that intrigues Dr. Dodman. Bull terriers have physical characteristics, including an arched palate and pronounced ears, that are similar to people with a condition known as Fragile X Syndrome. And Fragile X Syndrome tends to be paired with certain autistic-like traits.
There’s more. When Dr. Dodman collected blood samples from bull terriers, he found that those who had autism had significantly higher levels in the blood of an amino acid called neurotensin than dogs unaffected by the condition. The same difference can be found in children with and without autism.
“This could only mean one thing,” Dr. Dodman writes in his book. “Our tail-chasing dogs were almost certainly autistic.”
So is it a done deal?
“Many of the behavioral issues of dogs share similarities with symptoms of human autism,” Dr. Borns-Weil says. “Dogs with canine compulsive disorder [equivalent to human obsessive compulsive disorder] have repetitive movements that may appear to resemble autism. And there are dogs who do not seem to communicate with other dogs appropriately, appearing to have social pragmatic issues that are also a signature trait found in people who have autism. Some dogs may also have difficulty controlling their impulses and have sudden outbreaks of aggression.”
Yet for all that, she says, “While canine autism is an intriguing idea, I am cautious about making a diagnosis of autism in my patients at this point. I am not saying that autism spectrum disorders in dogs don’t exist. And perhaps when autism is better understood in people, it can be appropriately characterized in dogs. But right now, the autism-like behaviors that I encounter in my patients can be better described by other diagnoses,” often relating to anxiety.
By which she means that in her experience, certain behaviors that seem like autism in dogs, such as poor communication skills with other dogs, can generally be traced back to stressors in the environment that cause behaviors that seem autistic, or even traced back to a dog’s inherent personality. For instance, she says, there are events that might occur during a dog’s critical socialization window — weeks three through 12 — that might prevent him from learning how to “read” other dogs or people. Perhaps something traumatic caused him to withdraw as a coping mechanism. “As a result, he may be unusually avoidant of social interaction or even become aggressive when forced to interact,” she explains. In some cases, poor training may lead to what appear to be anti-social, autistic-like behaviors.
It’s also possible that repetitive behaviors will become part of a dog’s way of managing after he has been prevented from engaging in normal movements. Being cooped up in a crate for a prolonged period may cause a dog to pace or spin repetitively, for example. While such behaviors are similar to what is referred to as stimming in children with autism — actions employed to let off excess excitement — they come about for different reasons in dogs and do not in and of themselves point to canine autism. Rather, when a dog is brought to Dr. Borns-Weil because of repetitive behavior that occurs even in the absence of stress or the absence of abnormal living conditions, a diagnosis of canine compulsive disorder is more likely to be made.
In terms of inherited traits. Dr. Borns-Weil points out that some dog breeds simply are more sociable than others. That’s why families with small children might be more inclined to consider an interactive, easy-going dog like a golden retriever rather than say, an aloof chow or Weimaraner.
Dr. Borns-Weil points out, too, that autism spectrum disorders in people, which “are still not well understood,” are characterized by a limited ability with language. You can’t even apply that very common standard when talking about a dog. Language is not part of their communication repertoire.
At the end of the day
While Dr. Borns-Weil is more conservative about diagnosing autism in dogs than Dr. Dodman, they agree that traits in dogs that resemble autism and also compromise a pet’s quality of life need to be managed, and they are essentially in agreement about the arsenal of treatments available. For instance, a dog with repetitive behavior, whether you call it autism or canine compulsive disorder, needs a regimen of behavior modification in conjunction with an anti-anxiety drug such as an SSRI (Serotonin Reuptake Inhibitor) like Prozac. A shy or reserved dog might need extra TLC, or he might simply need to be accepted for the personality he has.
Comparative medicine looking at similarities between dogs and people is only ramping up and will surely yield more answers in the future about whether autism truly exists in the canine species. For now, the best option, if your feel your pet is not acting the way you would anticipate, is to love him for who he is and to do whatever you can with lots of attention and possibly drugs, to try to bring him out of any compulsive or other behaviors that might be making him miserable.