A Brief History of Scientific Experiments on Cats

A few weeks ago, the animal testing lab at the University of Wisconsin-Madison quietly shut its doors following an aggressive two-year campaign against the laboratory's use of cats by the People for the Ethical Treatment of Animals. In a series of heartbreaking accusations, PETA alleged that an orange tabby named Double Trouble was the subject of multiple ear, skull, and brain surgeries, during which her head was immobilized with a stainless steel post and her ears were chemically deafened via an injection. During one surgery, PETA says, Double Trouble "woke up to what was likely a painful and horrifying experience as experimenters were cutting into her head and skull," and later the cat was trapped in a nylon bag for sound localization research. The group also accused UWM of starving the cat, and eventually killing and decapitating her after her head wound became too infected, three months following the original surgery.

But despite claims of conditions, multiple investigations conducted by the US Department of Agriculture and the National Institutes of Health concluded that the lab was not in violation of any ethical or hygienic standards, and although the USDA fined UWM $35,000 last year, all of the citations were for bureaucratic mismanagement related to reporting animal injuries and deaths, and not the injuries and deaths themselves. Although PETA seemed to take credit for the shutdown, UWM released a statement stating that the lab had actually closed due to the retirement of its 70-year-old head researcher, noting that "work in the lab was highly regarded scientifically and yielded important insights into how the brain localizes sound, knowledge important for such things as hearing and cochlear implants."

The fight between animal rights activists and the scientific community is an ongoing struggle, particularly when it comes to to felines. Although the UWM lab experimented with dogs, gerbils, and pregnant monkeys (all of whom also died), research on cats is especially controversial since we tend to think of them as more than just animals. From a scientific perspective, though, cats are especially useful in experiments—since famed behavioral psychologist Edward Thorndike's cat-based learning experiments in the late 1800s, researchers have discovered that when it comes to approximating the human brain, particularly in the areas of neurology, ophthalmology, and immunodeficiency, cat brains are the closest match we can find without resorting to people.

According to cat researcher Dr. Nicholas Dodman, "Cats have frontal, temporal, occipital, and parietal lobes of their cerebral cortex, as we do, and these brain regions are composed of gray and white matter, as they are in humans. And the various brain regions are connected in the same way as they are in humans and identical neurotransmitters are employed in conveyance of data." The same parts of our brains even light up when cats and humans go to take a piss. The point is, cat brains might as well be tiny human brains, which makes them extremely useful.

Primates also have brains that resemble ours, but as more and more countries extend basic rights toward gorillas, orangutans, chimpanzees, and bonobos, the moral gray area of experimenting on primates is severely limited. Cats, by comparison, are relatively unprotected and are very, very easy to find. According to the ASPCA, shelters in the United States take in roughly 3.4 million stray cats every year, 1.4 million of which are euthanized. Some shelters have argued they should be allowed to sell animals who are scheduled to be put down to labs, but nowadays, most lab cats are bred by USDA-approved vendors, primarily because they are more docile and disease-free. (Some shady characters have been known to kidnap pets and trap strays to resell to labs, which called bunching.)

The father of animal experimentation, 19th-century physiologist Claude Bernard, used stray cats extensively throughout his career, cutting them open to study how the pancreas aided digestion and the liver processed sugar. In reference to his vivisections, he wrote, "The physiologist… does not hear the animals' cries of pain. He is blind to the blood that flows. He sees nothing but his idea, and organisms which conceal from him the secrets he is resolved to discover."

In 1988, the American Medical Association published a letter defending experiments on animals, arguing, "Virtually every advance in medical science in the 20th century, from antibiotics and vaccines to antidepressant drugs and organ transplants, has been achieved either directly or indirectly through the use of animals in laboratory experiments." But the history of catsperimentation is rough and messy.

In the late 50s and early 60s, Yale professor José Delgado figured out a way to manipulate a cat remotely through the implantation of a quarter-sized electro-receiver, called a stimoceiver, into its brain. It worked by relaying impulses to trigger physical and emotional reactions via an FM radio transmitter. Following his research on cats, he went on to put these remote-controlled devices into monkeys and bulls, which included a notable moment where a bull was stopped cold in the middle of a charge after his implant was fired. Eventually Delgado implanted stimoceivers into human mental patients and found that, like in cats and bulls, he could get implanted humans to move involuntarily, or fly into a rage; one participant smashed her guitar in the middle of a song when stimulated.

During that same era, the government funded experiments where cats were given LSD. Once dosed, the cats freaked out, like most people who are spiked with acid. In one video taken at the time, it appears that the cat is having some sort of horrible rigid seizure; in another, the cat seems completely terrified about a couple of mice in its cage despite having literally just killed one before being dosed. Whether scientists were able to glean any information from all this isn't clear.

In 1958, roughly two years after the acid cats, a pair of notable researchers named David H. Hubel and Torsten Wiesel inserted a microelectrode into a cat's eye, strapped it down into a Clockwork Orange–type movie theater seat, and forced it to view a variety of images, which helped them decipher how the brain can develop complex visual images from simple visual stimuli, and was instrumental in the theory of hierarchical vision processing. These experiments also led to the development of a widely-used computer algorithm for image object recognition called SIFT. In 1981 the duo received a Nobel Prize for their work in visual neuropsychology, after sewing shut a newborn kitten's eye for six months and studying the effect of unilateral vision on the primary visual cortex in the brain. They discovered that even after opening the cat's eye later, its vision processing never fully recovered.

A more recent—and more controversial—neurobiologist, Colin Blakemore, conducted a similar study in the 1980s where he deprived newborn kittens of relatable visual stimuli by keeping them in total darkness. Once in a while he'd place them into a container with striped walls, prevented from seeing even their own bodies by a restrictive collar. After a few months of this, they were placed into a normal environment in order to examine how the visual cortex develops. At first the cats wouldn't flinch when something was thrust at them, nor would they place their paws on a surface they were being lowered toward, suggesting a break between motor function and visual stimulus. Yet after a short period of time, these normal reactions materialized, despite the cat having never developed that part of its brain. Blakemore also performed the Hubel and Wiesel eye-sewing experiment, which led to effective treatments for children with lazy eye as well as tools to combat childhood blindness.

Cats have also been experimented on in the name of understanding diseases. Both leukemia and HIV have analogues in cats: the feline leukemia virus and feline immunodeficiency virus. In particular, FIV is so closely and profoundly related to HIV that by studying the AIDS virus in cats, scientists at the University of Florida and University of California, San Francisco recently discovered a protein in FIV that triggered an immune response reaction in HIV-infected humans, despite the fact that neither cats nor humans can cross-infect each other with their respective diseases. This discovery could potentially bring researchers closer to an HIV vaccine for humans, and compared to earlier experiments, this groundbreaking discovery involved relatively little pain and suffering on the part of cats.

The question undergirding all of this is whether it is morally and scientifically acceptable to take advantage of the limited protection offered to cats—as opposed to humans or monkeys—in the search for useful knowledge. Would scientists be just as willing to sew an infant's eye shut if it meant fewer blind children? Where, exactly, is the defining line between the pursuit of science and an ethical obligation to avoid causing pain to a living being? A lot of different people have a lot of different answers to those questions; what seems acceptable to some may sound like an atrocity to animal activists. For now, at least, experiments at cats seem certain to continue.

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