Обезьяны из Силвер-Спринг: Дело о жестоком обращении и нейропластичность.

Macaques used in neuroplasticity research; subjects of an animal cruelty court case

The Silver Spring monkeys were 17 wild born macaque monkeys from the Philippines who were kept in the Institute for Behavioral Research in Silver Spring, Maryland. The monkeys had been used as research subjects by Edward Taub, a behavioral neuroscientist, who had cut afferent ganglia that supplied sensation to the brain from their arms, then used arm slings to restrain either the good or deafferented arm to train them to use the limbs they could not feel. In May 1981, Alex Pacheco of the animal rights group People for the Ethical Treatment of Animals (PETA) began working undercover in the lab, and alerted police to what PETA viewed as unacceptable living conditions for the monkeys. In what was the first police raid in the U. S. against an animal researcher, police entered the Institute and removed the monkeys, charging Taub with 17 counts of animal cruelty and failing to provide adequate veterinary care. He was convicted on six counts; five were overturned during a second trial, and the final conviction was overturned on appeal in 1983, when the court ruled that Maryland's animal cruelty legislation did not apply to federally funded laboratories. the transformation of PETA from a group of friends into a national movement, the creation of the first North American Animal Liberation Front cell, and the first animal research case to reach the United States Supreme Court. In July 1991, PETA's application to the Supreme Court for custody was rejected. Days later, the last two monkeys were killed after veterinarians determined they were suffering and should be euthanized. During the subsequent dissection of the monkeys, it was discovered that significant cortical remapping had occurred, suggesting that being forced to use limbs with no sensory input had triggered changes in their brains' organization. This evidence of the brain's plasticity helped overturn the widely held view that the adult brain cannot reorganize itself in response to its environment.

Edward Taub (born 1931) is a behavioral neuroscientist currently based at the University of Alabama at Birmingham. He became interested in behaviorism while studying philosophy at Columbia University and went on to study under Fred Keller and Wiliam N. Schoenfeld, the experimental psychologists. He took a job as a research assistant in a neurology lab to gain more understanding of the nervous system and became involved in deafferentation experiments with monkeys. An afferent nerve is a sensory nerve that conveys impulses from the skin and other sensory organs to the spine and the brain. Deafferentation is a surgical procedure in which the spinal cord is opened up and the sensory nerves cut so that these impulses do not reach the brain. A monkey whose limbs have been deafferented will not feel them, or even be able to sense where they are in space. At his trial in 1981, Taub told the court that deafferented monkeys are notoriously difficult to look after, because they regard their deafferented limbs as foreign objects, mutilating them and trying to chew them off. Taub continued working with deafferented monkeys at New York University, where he obtained his Ph. D. in 1970. Engaged in what he saw at first as pure research, he conducted several kinds of deafferentation experiments. He deafferented monkeys' entire bodies, so that they could feel no part of themselves. He deafferented them at birth. He removed monkey fetuses from the uterus, deafferented them, then returned them to be born with no sense of their own bodies.

Alex Pacheco (born 1958) was a graduate student at George Washington University when he volunteered in May 1981 to work as a research assistant in Taub's lab. The Washington Post writes that he was raised in Mexico, the son of a doctor, and wanted to become a priest. He took a tour of a slaughterhouse in the 1970s and said it changed his life; he read Peter Singer's Animal Liberation (1975), stopped eating meat, and became an animal rights activist. He worked on the anti whaling ship, the Sea Shepherd Conservation Society, joined the Hunt Saboteurs Association in England, and when he returned to the United States to study political science at George Washington, he teamed up with Ingrid Newkirk, a local poundmaster, to form People for the Ethical Treatment of Animals in March 1980. The point of taking the research position in Taub's lab was to gain firsthand experience of what happens in animal research laboratories, so he looked through a list of government funded labs and chose the one nearest his home in Takoma Park. Pacheco writes that 12 of the 17 monkeys had had one or both arms deafferented, while according to the Laboratory Primate Newsletter 10 had undergone deafferentation, the seven others acting as the control group. The researchers had named the monkeys Chester, Paul, Billy, Hard Times, Domitian, Nero, Titus, Big Boy, Augustus, Allen, Montaigne, Sisyphus, Charlie, Brooks, Hayden, Adidas, and Sarah. Sarah, the lone female, was a control subject, which meant she had been left intact. She had been purchased from a dealer, Litton Laboratories, when she was one day old, and had lived since then, for eight years, in the institute. Paul was the eldest. He had had one arm deafferented. He had chewed off all the fingers on that hand and pulled the skin and flesh off the palm, exposing the bone. Billy had undergone surgery to deafferent both arms and used his feet to pick up food pellets. Taub's research assistant, John Kunz, a graduate student, said it was simply that the caretakers took advantage of Taub's absence to have a holiday of their own. Norman Doidge wrote in 2007 that, according to Taub, the monkeys in the photographs had been placed in positions that were not part of the laboratory procedure, a claim Pacheco denied. As for the dirt, Taub said "monkey rooms are dirty places," and that it was normal in laboratories for fecal matter to lie on the floor and food to drop through the cage bottoms into waste trays. He said employees had used brooms and mops on the floor and had emptied the waste trays nearly every day. He said the monkeys had been given fresh fruit twice a week, and that he disagreed with the veterinarians who testified for the prosecution that the female monkey, Sarah, was underweight. William Raub and Joe Held, officials at NIH, wrote in the Neuroscience Newsletter in April 1983 that deafferented monkeys kept at NIH since May 1981, and subjected to the same surgical procedures, had not developed lesions comparable to those in five of the deafferented monkeys from Taub's lab. "Based on these observations," they wrote, "it would appear that fractures, dislocations, lacerations, punctures, contusions, and abrasions with accompanying infection, acute and chronic inflammation, and necrosis are not the inevitable consequences of deafferentation." In 1991 neuroscientist David Hubel, referring to both the Silver Spring monkeys case and a PETA film about the University of Pennsylvania's head injury clinic in 1984, said the science was sound, that the people involved were not cruel, and that at the time there was a "laxness of standards" in animal care that, he wrote, would hardly be conceivable today.

According to Peter Carlson, every aspect of the case was disputed by experts on both sides during the first trial in October 1981. The prosecution said that Taub's lab was filthy and unhealthy, and federal inspection reports and witnesses supported the charge. Taub said the lab was no dirtier than any other, and he also produced federal inspection reports and witnesses to support his position. Veterinarians speaking for the prosecution said Taub's failure to bandage the monkeys' wounds was a threat to their health; veterinarians for the defense, including two who had worked with monkeys whose limbs had been deafferented, said bandaging them would cause the animals to attack the limbs. Carlson writes that the prosecution produced 70 photographs of dirty conditions and injured monkeys, while researchers who had worked in the lab testified for the defense that they had never seen the lab looking like that. The judge—District Court Judge Stanley Klavan—found Taub guilty of six counts of cruelty to animals for failing to provide adequate veterinary care in respect of six of the monkeys and acquitted him of the other 11 charges against him. He fined Taub $3,000. The laboratory assistant, John Kunz, was acquitted of all 17 charges. They were later removed to the Tulane Regional Primate Research Center in Covington, Louisiana, still under the care and control of the NIH. Two primate sanctuaries, Moorpark College in California and Primarily Primates in Texas, offered them a permanent home, but the NIH refused to release them. The monkeys were moved by the NIH to the Delta Primate Center in June 1986, where animal rights activists, who had been able to visit and groom the animals at the previous center, were told they could no longer see them. In 1987, the custodians of 14 of the remaining monkeys recommended that eight of them be euthanized, because they were judged to be beyond hope of resocialization. A lawsuit filed by PETA and others sought to block euthanasia and transfer the animals to a facility under their control. The New England Anti Vivisection Society and PETA ran ads in The New York Times on December 26, 1989, The Washington Post on December 27, and in The Washington Times on January 3, 1990, asking President Bush to save the monkeys, and concerned citizens to petition the White House. PETA also hired Tom Vice, a consultant veterinarian associated with the non profit Primarily Primates to assess Billy, one of the monkeys set to be euthanized by Tulane. Billy had two disabled arms, extensive pressure wounds, diaper rashes, bone infections, and kidney damage from antibiotic use. Vice's recommendations to proceed with the euthanasia was rejected by Pacheco and PETA's lawyers. One of the Tulane veterinarians caring for the monkeys, Marion Ratterree recalled, "We were standing here when he made the call. He was shocked. We were shocked." After the court denied custody to PETA, two of the monkeys, Titus and Allen, were kept for the National Institutes of Health at a Tulane University primate center, where they were later euthanized. On January 10, 1990, Tulane successfully argued to euthanize Billy in the U. S. District Court of Appeals, doing so 4 days later. The rejection of Vice's assessment was subsequently reiterated by Gerone on radio appearances and in letters, saying "We had them [PETA] by the short hairs and twisting when Billy was sick and their own vet recommended he be put down and they said no so much for PETA's concern for the welfare of animals." During these experiments, scientists discovered an unpredicted change in thalamus structure apparently caused by progressive nerve degeneration through the dorsal root ganglia (which were severed) and the dorsal columns all the way to the thalamus (a second order synaptic target).

Based in part on his work with the Silver Spring monkeys, Taub went on to develop novel physical therapy techniques to help stroke victims, and those with other forms of brain injury, regain the use of affected limbs. The American Stroke Association regards Taub's therapy, known as constraint induced movement therapy (CI), as "at the forefront of a revolution" in the treatment of stroke survivors. With CI therapy, the patient is forced to use the affected limb, to whatever minimal extent he can, by having the unaffected one restrained. The affected limb is then used intensively for three to six hours each day for at least two weeks. As a result of engaging in repetitive movements with the affected limb, the brain grows new neural pathways that control the limb's use, as a result of which stroke victims who were seriously disabled for many years have reportedly regained the use of limbs that were almost completely paralysed.