Animal Models of Human Psychiatric Disorders

For twenty years I have realized that the behavior problems I see in pet animals, especially dogs, are for the most part facsimiles of conditions psychologists and psychiatrists see in people. Human psychiatric conditions are diagnosed with reference to a manual known as the DSM (Diagnostic and Statistical Manual of Mental Disorders).

 

Many of the conditions referred to in there are also seen in a veterinary behaviorist’s caseload. Dogs are presented with mood disorders, anxiety-related conditions, phobias, sleep disorders, impulse control disorders and compulsive disorders. There are some differences, of course. Dogs don’t get substance- related disorders and, as far as we know, do not get bulimia, body dysmorphic disorder, schizophrenia, Tourette’s syndrome or depression. That said, similarities abound and some remind us of our human foibles.

 

The belief that study of (non-human) animals may teach us something about ourselves is called the animal models concept. My interest in compulsive disorders and belief in them as “animal models” of human OCD attracted the attention of the magazine SCIENCE. Last Friday a reporter from this prestigious magazine attended cases with me and grilled me for the entire day about my biological approach to understanding behavior problems in both animals and people.

 

Some psychiatrists, I told the reporter, seem to have an anthropocentric view of the world, apparently looking down at the rest of the animal kingdom from an evolutionary mountaintop. Veterinarians, like myself, however, are quite used to extrapolating from species to species. I belive this extrapolation is quite valid because we share a lot of the same DNA with animals (95% in the case of dogs) and have many genes in common (around 50%). Our brains are structured similarly and have the same centers and neurotransmitters. The difference is only a matter of proportions.

 

I’m not sure how the article in SCIENCE will turn out but it will no doubt be point- counterpoint presentation. I hope the reporter pay due homage to the remarkable similarities that exist across the species and will see the bottle as half-full rather than half-empty. The similarities, to my mind, outweigh the differences. After all, we’re all mammals in this life together.

 

Dr. Nicholas H. Dodman

 

Dr. Dodman will be presenting a two-day seminar at Narnia Pet Behavior & Training in Plainfield, Illinois on Saturday, the 24th and 25th of April, 2010. For anyone interested, please check out “Events” on his website, ThePetDocs.com

Comments

This seems rather rudimentary to me.  I'm a paramedic by trade and most of what I do to treat human emergencies was either discovered or refined as a result of animal studies.  The only difference between many veterinary medications and those intended for humans is the price and my vet has sent me off to the (human) pharmacy more than once for something that one of my dogs needed.  Since any animal with a central nervous system (including reptiles) can be trained using the same methods it should seem obvious that our brains work the same way. 

Of course, I haven't seen the "counterpoints" and perhaps doing so will create the same dissonance as that of "anthropocentric psychiatrists".  The article should make for some interesting and perhaps entertaining reading.

Swanny

A good dog is so much a nobler beast than an indifferent man that one sometimes gladly exchanges the society of one for that of the other.” William Francis Butler

There are experimental animal models of depression (learned helplessness model) that show similar neuroendocrine changes as seen in humans who are depressed.  OCD is clearly an issue in animals.  In 1992 an early paper compared canine acral lick dermatitis with human OCD.  This was very interesting to me as we had a Siberian Husky who had developed a rather large lick granuloma.  I gave him fluoxetine 20mg daily for awhile and he stopped the licking.  He was able to have surgery to remove the 1+ cm granuloma and healed without problem.  An interesting observation was that he used to turn around in circles several times (3-4-5 at least) before lying down.  After being on fluoxetine for several weeks, he would turn about 1/2 circle and lie down!  This was clearly another compulsive behavior.

After 3-4 months, I lowered the dosage to 20 mg every other day (works fine due to the long half-life of fluoxetine), and slowly tapered over a year.  He came off of the meds and the symptoms never recurred (although he might take a tad longer to lie down, but not like had had previously done).  That was different from most humans as OCD symptoms will tend to return without meds.

Humans also benefit substantially using cognitive-behavioral techniques, which obviously differentiate themselves from canines.  Optimal treatment combines both in humans.  Humans ARE substantially different from canines, although the similarities are obviously there.  We have a moral conscience, which clearly animals do not.  Even though animals can be trained to learn 'right and wrong' from a behavioral viewpoint, there is no evidence that they have any grasp of OBJECTIVE right/wrong, only conditioned responses layered on instinct.  Humans may certainly override moral conscience, but other than a few severely damaged humans, most all of us intuitively understand that there are objective morals. 

These last comments do not at all diminish the common ground, and usefulness of extrapolating some data between species...and both benefit!

This is an area I have been itching to study for ages! Next time I get the chance to submit an area of special interest it will be on the similarities between human and dog mental illness. Self harm?? stressed dogs may chew their own legs to relieve stress..stressed teenagers may harm themselves for similar reasons. The brain chemistry here is similar. Depression, panic attacks or separation anxiety.. the list goes on. What differs, I feel, between humans and dogs, of course, is the thought processes and rationalizing the situation. The brain chemistry and the behaviour must be linked. Needs a good, detailed study.

If you think about it, dogs display traits of autism as well.  I have a son with autism and from the time I began working with dogs, I realized that the similarities are there.  Dogs need to be socialized their entire life, so do chidren with autism, dogs tend to do repetitive behaviors, so do children with autism, dogs learn visually, so do children with autism, dogs respond to posititive training methods, so do children with autism, dogs need to generalize their skills, so do children with autism, dogs need repitition in training methods to learn the behavior, so do children with autism, when asked to do something they do not understand, dogs perform "displacement" activities to escape the activitiy, so do children with autism.  This list just goes on and on.  Once I realized the similarities in how my son learns and how my dog learns, dog training became so much easier and my dog and I both became happier!  Oh, and now you can use "clicker training" to work with kids too!  www.tagteach.com

I just can't help but point out how much I appreciate the work that Dr. Dodman has done over the years including his lovely books.  It's about time that an entity such as SCIENCE interview him.  I really hope that they can do him justice!

Dr. Audrey Long, DC

Very interesting!  I am a light-force chiropractor and intuitive energy healer.  I recently began working with animals as I've observed that animals mirror back to us our own dis-ease and disorders.  When a client shows up with an issue with their animal, I check in to see what the mind-body patterns are in the owners.  Usually when the energy shifts in the human, the animal no longer expresses dis-ease.