Mental Disorders in Animals
(Photo by Julie Corsi.)
Above is an image of a captive parrot that suffers from excessive feather-plucking, or pterotillomania. People who work with captive parrots or own parrots as pets have probably at least heard of this disorder, or even observed it firsthand. The parrot may have an excellent diet and be in good physical condition, yet it will continue to pluck and pluck at its own feathers, shaving itself bald in places.
If the cause is not a disorder of the body, then, can we say that this is a symptom of a disorder of the mind?
That brings up another question, though: how can we possibly know what is happening in an animal’s head? How can we separate an animal’s behavior into that of bodily needs and that of mental needs? People like to point out all the time that you can’t sit a dog on a couch and ask him what his childhood was like; we don’t even know if a dog’s memory of his childhood exists in any form that a human would recognize. While I think most people would agree that animals have minds, they function- by necessity and evolution- in ways ours do not.
I think this has to be the focal point of the following discussion: animal minds and human minds are different. Am I saying animal minds are inferior? Certainly not. But I’d like to point out that a lot of the research on mental disorders in animals focuses on finding parallels with human mental disorders. Yet the underlying reasons for disordered behavior in animals may be because they have mental needs that humans do not. For example, a popular theory behind why parrots develop pterotillomania is because they are not given ample opportunities to perform normative food-foraging behaviors.
So what forms of mental disorders are present in animals, and what are biologists, psychologists, veterinarians, and pet owners doing to better understand them?
Below the cut I’ll be discussing several things that people may find distressing/triggering: animal suffering, mental illness (including references or descriptions of the most commonly diagnosed human mental disorders), and animal research. It’s an upsetting topic, which is why I’m writing about it much more formally than I normally do, but I think it’s both interesting and important.