Zoobiquity

  But as to why they do it, the short answer is that we don’t really know. Psychiatrists have linked cutting to adolescence, control issues, emotional imperceptiveness, and an inability to talk about feelings. Self-injury has also been associated with childhood sexual abuse and such other mental conditions as borderline personality disorder, anorexia nervosa, bulimia nervosa, and obsessive-compulsive disorder (OCD). Patients who self-harm report being stressed and anxious, overwhelmed by expectations and choices—or completely isolated and numb.

  Childhood traumas and abusive parents have traditionally been blamed for self-mutilating behavior. But this formulation, it turns out, is incomplete. The stereotypical cutter featured in movies and on TV may be a sexually abused, poorly parented borderline girl. But it turns out that rates of self-injury may be roughly similar for men and women. The difference is more in how they do it: men tend to hit or burn themselves, while women usually cut. Some begin the behavior as young adults when they’re no longer under the influence of their parents. And many report no history of childhood abuse.‡

  So the mystery remains. What flicks the switch—changing brooding, hormonal adolescents, and full-grown adults with jobs and responsibilities into self-injurers?

  I decided to see what insights a zoobiquitous approach could add. When we find animal behaviors that parallel disturbed human actions, it’s an opportunity to look beyond our “hectic modern lives” and “big human brains” for the origins of the symptom. Yet when I first began asking whether animals self-injure, the question seemed almost absurd. What would it even mean for an animal to mutilate itself?

  The classic image of animal self-harm is a wolf gnawing off a paw to free himself from a hunter’s snare. But this purposeful self-injury to escape entrapment (which crops up from time to time in extreme human accounts as well) was not what I was looking for. I sought an animal correlate to the compulsive, trancelike self-injury seen in humans. Needless to say, I could safely assume I would find no evidence of razor blade cuts or cigarette burns among our wild cousins.

  And I didn’t. But my research quickly turned up an equally fearsome arsenal, usually deployed against enemies. Teeth. Claws. Beaks. Talons. The big question was, do animals ever turn these on themselves? The answer, to my astonishment, was yes, and frequently. Feather-picking disorder in birds was just one of many such examples well known to veterinarians.

  A friend of mine once took her cat to the vet assuming it had a skin affliction that was causing all the hair to fall off its legs, revealing red, oozing sores. After some tests to rule out parasites and systemic diseases, her vet said her pet was a “closet licker.” It’s a common diagnosis for house cats, sometimes called psychogenic alopecia. Out of sight and in secret, the cat was injuring itself with no clear physical trigger, just like a human cutter alone in her room.

  Owners of golden retrievers, Labrador retrievers, German shepherds, Great Danes, and Doberman pinschers will probably recognize a condition that often affects those breeds—in which they obsessively lick and gnaw at their own bodies. The open sores they create can cover the entire surface of a limb or the base of the tail. The diagnosis of acral lick dermatitis (sometimes called lick granuloma or canine neurodermatitis) is not linked to an external agent like a fungus, fleas, or infection; the animal is doing it for no apparent physical reason. If you’ve ever watched a dog chew itself like that, it sometimes seems to be in a kind of trancelike or hypnotic state—eyes glazed, head bobbing, lick … lick … lick … lick …

  Anyone who’s worked in the reptile section of a pet store has seen turtles biting their legs and snakes chewing their tails. And a peek into the stable shows another suffering animal. “Flank biters” are horses that violently nip at their own bodies, drawing blood and reopening wounds. The owners of these horses, like parents who discover their teenager is cutting, are often confused and heartbroken by the behavior, which can include bursts of violent spinning, kicking, lunging, and bucking.

  Behaviors such as flank biting, tail sucking, and feather plucking may be more common than we think, at least in certain breeds. Up to 70 percent of Dobermans, for example, will develop time-consuming and often distressing repetitive actions, including but not limited to self-injury. Nicholas Dodman, a veterinarian at Tufts University, treats and researches compulsive behaviors in horses and dogs. Dodman and his colleagues at the University of Massachusetts and MIT have identified a genetic region on canine chromosome 7 that is associated with an increased risk of a dog’s developing what they call canine compulsive disorder (CCD).

  Whether OCD in humans and CCD in dogs are the same disorder is hard to say. In human beings we make a diagnosis of OCD when obsessional thoughts drive compulsive behaviors. In contrast, with animals, all veterinarians have in order to make a diagnosis are the behaviors. Without a common language, they have no way of determining whether obsessions underlie the animal’s perseverative practices.

  When owners bring in pets who circle furniture for hours, do backflips to the point of physical exhaustion, or rub their skin to the point of breakage and bleeding, veterinarians sometimes describe these behaviors as “stereotypies.” At the extreme end of the spectrum are head banging, picking, poking, and gouging. In some cases, especially in birds, compulsive vocalization is considered a stereotypy with possible connections to Tourette’s syndrome in humans. For veterinarians, any behavior on this spectrum, even the milder end, merits concern and intervention.

  Many of the compulsive behaviors seen in horses, reptiles, birds, dogs, and humans share core clinical features, including the potential to cause suffering and profoundly disrupt a patient’s life. But many also share an intriguing connection to cleaning activities. You’ve probably heard about the repetitive hand washing practiced by many OCD sufferers. Similarly, a stressed cat may go overboard with a feline’s cleaning tool of choice, its raspy tongue. Veterinarians have come up with a colloquial term that cuts right to the heart of what’s going on here. They call it, simply, “overgrooming.”

  Overgrooming? When I first heard the term, I flashed on countless nature documentaries showing apes combing and nit-picking each other. It surprised me that this benign cleaning and social ritual could escalate into something potentially lethal. I quickly learned that animal grooming covers both a broader range of species and a weirder array of behaviors than I’d ever imagined.

  Grooming, to put it plainly, is as basic an activity for many creatures as eating, sleeping, and breathing. Evolution probably favored nature’s neat freaks because they were the ones with fewer parasites and infections.

  Primates display a wide repertoire of combing and nit-picking techniques. Some chimps pick parasites off each other, place them on a forearm, and kill them with a smack of the hand before eating them. Others use leaves to pinch the bugs out of their partner’s fur. Japanese macaques have elaborate finger-and-thumb louse-egg–loosening techniques passed down from one generation to the next (through the maternal line).

  But while delousing may be its ultimate purpose, there’s a more immediate reason animals groom. Simply stated, grooming feels good, and it plays a vital role in the social structure of many animal groups.

  Some groups of chimps scratch each other’s backs and clasp hands without the intention of bug removal. Crested black macaques, especially females, embrace each other and rub their sides together. And while most mutual grooming in primates takes place among family members, non-kin also get their fingers in each other’s fur—for good reason. When lower-ranking bonnet macaques and capuchins “give” grooming, they gain in return protection, backup in fights, and a chance to hold someone else’s baby. Some baboons groom to get close enough to a partner to sniff out whether he or she is aroused and in the mood for mating.

  The huge importance of social grooming isn’t limited to primates or even land mammals. In the fish world, it sometimes keeps the peace. A tropical reef dweller called the cleaner wrasse operates what are, in effect, underwater spas, where it eats paras
ites and scar tissue off other fish. These include much larger predators that would normally (and literally) eat the wrasses for breakfast. But in the calming atmosphere of the cleaning station, the wrasses approach the bigger fish without fear, darting around their teeth and even into their gills.

  This relationship isn’t just a heartwarming example of animal cooperation. Scientists have found that grooming’s calming effect is felt not only by the fish receiving the cleaning but also by fish waiting their turn. Both the anticipation and the experience of grooming seem to make the predator fish less likely to chase any fish in the area. The scientists who did the study compared this aquatic “safe zone” to a human barbershop in a rough neighborhood where violence is understood to be off-limits.

  Grooming’s powerful calming effect applies as much to solo as to social cleaning rituals. Cats and rabbits may spend up to a third of their waking hours fastidiously licking themselves. Sea lions and seals spend many hours a day rifling through their own fur. Birds roll in dirt, fluff, preen, and pick with their beaks. Snakes, lacking napkins or hands with which to wield them, often finish a meal by wiping their faces against the ground.

  But perhaps no animal has more, or more varied, grooming routines than our own species. Humans primp, wash, and polish … alone, in pairs, in groups … with and without tools or “product” … for free and for price tags verging on the obscene. I’m just one of millions of American women—and, increasingly, men—who find relief at the manicurist or the hair salon when confronted with the stresses of career and family. In fact, I would say that regular and good grooming calms and centers me. The companionship, the care, and, especially, the repetitive tactile stimulation relieve stress and enhance my well-being.

  Our species, as a rule, grooms a lot. And as it does for our animal cousins, grooming provides us with physical pleasures: the joy of a warm shower after a week of camping; the satisfying smoothness of a good shave; the indulgence of having attention lavished on us at a salon; and the frisson of looking in the mirror when we’re dressed to the nines. (While humans vary in the amount of time and money they choose to spend on grooming, we know that opting out completely carries major social risks.)

  It turns out that our sense of well-being is much more than skin deep. Grooming actually alters the neurochemistry of our brains. It releases opiates into our bloodstreams. It decreases our blood pressure. It slows our breathing. Grooming someone else confers some of the same benefits. Even simply petting an animal has been found to relax people.

  When I’m sitting in the plush pedicure chair, my feet bathed in warm soapy water, it’s hard to believe there is such a thing as overgrooming. Or that this calming procedure could have anything to do with Princess Diana’s slicing lines in her thighs with a razor blade, let alone with a solitary cockatoo in his cage. But grooming encompasses more than just the socially acceptable forms you pay for at the spa.

  There’s also a more private form of grooming—small behaviors that all but the most virtuous of us engage in all the time and often unconsciously. In general, they’re innocent enough, but given the choice, we definitely wouldn’t want to show them in public or watch other people do them. Look at your own fingers, the ones holding this book. Are your cuticles smooth or are there some rough edges begging to be picked or nibbled off? Are you twirling a lock of hair around your finger, twisting your eyebrows, stroking your own cheek, massaging your own scalp? Studies looking at hair pulling, scab picking, and nail biting all point to a calm, trancelike state that typically accompanies these small, automatic, self-soothing activities.§

  And we unconsciously vary the intensity of these actions. Perhaps the fingers playing with your hair sometimes have the urge to pull a strand out. There’s that slight tension as the root clings to the follicle … you gently tug harder … and a little harder … until finally, there’s that short, sharp sting and the hair releases.

  Or imagine the last time you had a little scab somewhere on your body. Maybe you had the willpower to leave it untouched, but the rest of us probably scraped around its crusty edges with a fingernail, then maybe popped the whole thing off, before it was “ready.”

  Taking it a bit further, imagine the small satisfaction you get from squeezing a pimple. Those of you who can legitimately claim never to have done this may read the remainder of this paragraph in disgust. But the rest of us know the drill. Feeling along the smooth skin … finding a bump, and then—against all advice—squeezing … and squeezing … feeling the resistance, a prick of pain, until finally it pops and releases. Sometimes there’s blood. Once in a while we may even squeeze it again (very much against the dermatologist’s orders) and push out still more blood.

  Release … followed by relief. We’ve all felt it, and even if scabs, pimples, or ingrown hairs aren’t your thing, maybe you’ve bitten your cuticles or scratched your scalp or excavated your nostril a little too hard.

  In fact, human beings rely on this release-relief loop throughout the day. Stroking our hair, picking our toenails, chewing the inside of our cheek—these are powerful self-soothers. We may rub, pull, nibble, or squeeze a little more when we’re stressed, but for most of us the behavior never escalates. Folded into our daily lives, these activities help us maintain an activated yet calm state. But for some people the need for that feeling of release … and relief is so strong that they crave extreme levels of it.

  Release … and relief—those are the same reasons cutters give for why they cut. The same intensity and promise of sudden relief we might get from pulling a single strand of hair or picking a pimple, dialed way, way up, leads cutters to carve lines in their skin with razor blades. If we accept that this behavior is on the same spectrum as less destructive forms of grooming, as my veterinarian colleagues would suggest, then self-mutilation is truly grooming gone wild.

  In fact, the addition of genuine pain may even bolster grooming’s positive biochemical effects. It turns out that both pain and grooming cause the body to release endorphins—those same natural opiates that give marathoners their runner’s high. Pain also causes the body to produce catecholamines, which over time damage major organs but in the short term give the body a jolt—spiking the blood sugar, dilating the pupils, and increasing the heart rate. So in a way, self-mutilators are self-medicators, kick-starting their bodies’ natural and powerful chemical reactions. Some cutters report a trancelike state combined with an overwhelming need to self-mutilate—not unlike an addict jonesing for a drug, a jogger restlessly anticipating her 5K, or a glassy-eyed German shepherd licking his paw.

  As a cardiologist, I was extremely interested to learn that, beyond altering blood chemicals, pain that is self-inflicted can sometimes affect the heart itself. Researchers in Massachusetts outfitted a group of rhesus monkeys known to be self-biters with tiny vests housing heart-rate monitors the scientists could check with a remote control. They found that when the monkeys naturally nibbled at their unfamiliar new ensembles, their hearts showed no significant spike or drop. But when the monkeys bit themselves, their heart rates were markedly elevated for thirty seconds before the behavior, then plunged dramatically the instant their teeth hit fur. A precipitous drop in heart rate—especially one that comes suddenly after it’s been elevated by thrill or fear—can create the feeling of calm. Like the self-biting rhesus monkeys, cutters (half-fearfully, half-excitedly) anticipating the moment when the blade hits their skin may be experiencing a mild tachycardia (increased heart rate), followed by a sudden, calming drop once the skin is broken and the blood flows.

  So one reason people and animals self-injure may be biochemical: they are caught in a neurotransmitter-based feedback loop in which their bodies reward them with calmness and good feelings after they do something that causes pain. And their hearts may be amplifying the feeling by slowing drastically right after racing with excitement.

  What’s interesting is how these two opposites—pleasure and pain, grooming and disfiguring—produce similar results in the body. So simil
ar that some people’s bodies seem to have mixed them up. Picking, poking, and chewing—which sometimes end up hurting us—stay in the gene pool because they’re on the same spectrum as grooming, which calms us down, keeps the peace, maintains our health, and binds our anxiety. But that still leaves us with a problem: whether it’s on a normal spectrum or not, self-injury in humans and animals is aberrant, dangerous, and needs to be controlled. Not only is it a sign of psychic distress, but it can cause serious health consequences, starting with nasty infections and ending with death.

  It’s here that veterinary medicine may offer new insights, or at least new paths, for human doctors to explore. Traditionally, psychiatrists have tried to understand self-harm through a checklist of personality disorders and evidence of past traumas. We might start by looking for a history of sexual abuse or features of borderline personality disorder. But our veterinary colleagues have a more direct approach. Lacking the ability to talk to their patients (and perhaps aided by this as well), they have identified the three most common triggers of self-injury: stress, isolation, and boredom.‖

  Call a veterinarian to treat a flank biter and she may inquire about the patient’s upbringing. (In a canine parallel, a puppyhood spent in a shelter is now recognized as a contributor to disturbed behavior in adult dogs.) Having ruled out a traumatic early “foalhood” and physical causes (say, a twisted bowel or torn ligament), she will then look for acute stress, isolation, and boredom.a

  To gauge stress, the veterinarian may investigate the animal’s social situation and environment. Is there a bully in the stable? Human or equine? Stress from feeling uncertain or insecure in its environment can lead an animal to self-injure.