字幕列表 影片播放 列印英文字幕 Science can be .... complicated. And I don’t mean all the math that’s involved. Or the jargon. Or the fact that you can do an experiment a dozen times and not get the same results twice. I’m just saying it can be … dicey. Like, we’ve told you before about Fritz Haber, the chemist who developed the technology that made fertilizer possible, and helped feed millions of people. Except he didn’t use his discovery for that. He used it to invent chemical weapons. In a similar way, most of the innovations that make all of modern space flight possible were developed to make ballistic missiles for Nazis. Now, when you think about it, the science in these cases was totally benign -- neither good nor bad. But sometimes, the things people learn from scientific endeavor can lead them to conclusions, and applications, that turn out to be just … well, just wrong. There are few better examples of this than the work of Portuguese physician Antonio Egas Moniz. Moniz pioneered a surgical procedure that, to his peers, was remarkably effective at treating many kinds of mental illness. It came to be adopted by neuroscientists, surgeons, and psychiatrists around the world, and especially in the US. But it soon proved to be, at its best, irreversibly destructive, and at its worst, inhumane. And yet Moniz was awarded the Nobel Prize in Medicine for it. It’s quite possibly the most regrettable Nobel Prize ever awarded. Because Moniz was given the Prize for developing the lobotomy. [Intro] The story begins with John Fulton, a Yale neuroscientist, in 1935. Fulton had spent the past five years cutting out sections of chimpanzees’ brains and studying how that affected their behavior. He was mostly working with the cerebral cortex, the outer layer of the cerebrum, which is the largest part of the brain. It’s also divided into four lobes. And each lobe is responsible for a different set of cognitive functions. The temporal lobe, for example, is located on the bottom of the brain and is associated with memory, sound and language. And the frontal lobe, at the front of the brain, is the home of our personality. It’s responsible for our higher reasoning, our emotions, motor skills, and attention span, among many other things. In 1935, scientists like Fulton were just beginning to understand how each of these lobes behaved. But most of their knowledge on the frontal lobe came from just a few studies, or records of brain injuries, like the case of a man named Phineas Gage. Gage was working on a railroad in 1848 when an accidental explosion lodged a railroad spike into his head. The spike stabbed right through his frontal lobe. Amazingly, Gage survived, and his memory was still in tact, but his personality was… different. He became kind of mean and aggressive, because the part of his frontal lobe that was damaged -- his orbitofrontal cortex -- was the part that’s responsible for emotions. And Fulton found that his results were similar, when he removed the orbitofrontal cortex from chimpanzees. He performed this procedure on two chimps named Becky and Lucy. And they quickly began exhibiting inappropriate behavior - defecating on the floor, throwing temper tantrums, generally just acting out of control. However... when Fulton removed their entire frontal lobe, they became more docile, relaxed, calm. Fulton presented his findings at the second annual international neurological conference in London in 1935. And in attendance was Antonio Egas Moniz. Now, in some ways, Moniz was a true renaissance man. He was a medical professor who served as the Ambassador to Spain during World War One. He was a successful legislator who wrote a series of popular books on human sexuality. And he was a flamboyant socialite who threw lavish parties and designed his wife’s evening gowns. He was driven, passionate, confident, and intelligent. In fact, by the time he had met Fulton in London, Moniz had already almost won the Nobel Prize, for developing one of the most important innovations in neurosurgery at the time. Back in 1925, he had wanted to figure out a noninvasive way to diagnose tumors in the brain. So he devised a concept called cerebral angiography, in which a solution of sodium iodide was injected into the carotid artery, in a patient’s neck. The solution would then flow into the brain. Since sodium iodine can’t be penetrated by most kinds of electromagnetic radiation, it rendered blood vessels opaque when viewed in an x-ray. And this allowed doctors to find problems in the brain’s blood vessels, caused by tumors and other obstructions. Moniz’s technique was a huge breakthrough in brain imaging, and it laid the foundation for methods we still use today to diagnose conditions like aneurysms. Moniz was nominated twice for the Nobel Prize, but was thwarted, some historians say, by a jealous Nobel chairman. But when Moniz saw Fulton’s presentation on his chimp research, he became newly inspired. Because, in addition to his work on brain-imaging, Moniz had spent years working with severely depressed, anxious and schizophrenic patients. And he had developed a theory -- not based on any empirical data -- that mental illness was caused by malfunctioning synapses, or connections between brain cells, in the frontal cortex. He believed it was these bad connections firing over and over again that led to obsessive thought patterns that tormented many of his patients. However, Moniz had no way of identifying which individual synapses were supposedly malfunctioning. So he proposed a procedure, based on Fulton’s work, to destroy the nerve fibers -- also known as the white matter -- that connects the frontal lobe to the thalamus, the structure deep in the brain that receives and relays sensory signals. By severing that connection, Moniz believed he could cut off the frontal lobe, and its broken synapses, from the rest of the brain, rendering it useless. Four months after the London conference, Moniz attempted this operation on a human for the first time. He didn’t perform it himself, because his hands were deformed with gout. Instead, he directed a lab assistant to drill two holes into the skull of a 60-year-old former prostitute suffering from psychosis. The assistant then destroyed the nerve fibers leading from the frontal lobe with two injections of pure alcohol. And the operation worked, in the sense that the woman stopped displaying the symptoms of psychosis. But it depersonalized her. Her disruptive thought processes seemed to have stopped, but so did all of her emotions. Essentially, it removed what made her human. And over time, Moniz performed the operation on nineteen other patients, eventually refining the procedure with the use of a leucotome, a tool resembling an ice pick that allowed him to experiment with which nerve fibers to cut. However, only a complete severing of the nerve fibers seemed to create the effects he wanted -- which was for the patients to no longer display any symptoms of anxiety, depression or schizophrenia. He called this technique the prefrontal leucotomy -- leuco meaning “white matter” in latin, and “tome” meaning knife -- and he published these findings in 1937. Moniz’ work soon caught on in the United States, where the number of psychiatric hospitals and patients had doubled since 1903. Leucotomy’s strongest proponent in America was neurology professor Walter Freeman, who was also present at Fulton’s chimp presentation and had corresponded with Moniz as he performed his experiments. Freeman and his assistant, Dr. James Watts, performed their first leucotomy on a Kansas housewife who suffered from a mood disorder. And after the surgery, her mood swings stopped. Subsequent testing showed that her memories were intact, as well as her movements and interactions with people. However, the doctors also noticed that her personality was essentially gone. While no longer impaired by her mood disorder, she was fundamentally impaired in many other ways. She simply... existed. In the ensuing years, Watts and Freeman standardized the leucotomy procedure and renamed it the standard lobotomy. They published a popular book about it in 1942, and after World War II ended and thousands of soldiers returned to America with post-traumatic stress disorder, the number of lobotomies performed a year grew from 100 to 5,000. The procedure became a kind of catch-all solution at American psychiatric hospitals for a multitude of symptoms including disorientation, insomnia, anxiety, phobias and hallucinations. Different versions of the procedure branched out, as well. The standard version gave rise to a transorbital lobotomy, in which a thinner version of the leucotome was pushed under the eyelid and into the frontal lobe with a mallet. The surgeon would then sweep the instrument around to sever the lobe’s connection with the thalamus. Despite the rising popularity of this surgery, there was soon plenty of criticism. As early as 1937, doctors had noticed that lobotomies caused strange, unexplained eye movements in some patients. In Chicago, psychologist Mary Francis Robinson assessed 90 patients who received lobotomies and discovered that most of them could no longer concentrate, they appeared unmotivated, and lost interest in their own lives. Their creativity was destroyed. Musicians stopped playing music; writers stopped writing. All of these darker symptoms, though, were overshadowed by what many psychiatrists saw as more stable outward behavior. The lobotomy’s vogue reached a peak in 1949, when Moniz, who was at this point considered the father of the procedure, was awarded the Nobel Prize in Medicine for his work. The lobotomy remained common until 1952, when a French pharmaceutical company changed psychiatry forever by introducing chlorpromazine, a medication that blocked dopamine receptors in the brain. Dopamine is a neurotransmitter, a chemical released by nerve cells that lets them communicate with other nerve cells. And it’s vital in regulating moods and emotions. Overactive dopamine systems can cause heightened emotions and conditions like psychosis, and the drug worked by blocking dopamine receptors on brain cells, calming their activity. With this new drug now available, there was no need for costly and dangerous surgery, and soon, the use of lobotomies decreased rapidly. Today, the lobotomy is considered dangerous and archaic, a blunt tool for treating the subtle intricacies of mental illness. And the careers of Fulton, Freeman and Moniz are thought by some to comprise one of the darkest chapters in medical history. Because, since their time, attitudes about mental health, and the ways we take care of it, have changed a lot. It’s been 80 years since John Fulton first described his experiments on chimpanzees. Today, conditions like depression, anxiety, and mood and personality disorders are all treated biomedically with drugs, along with different kinds of psychotherapy, like cognitive and behavior therapies. And instead of focusing on getting rid of the symptoms of mental illness, psychiatric treatment today aims to help patients stay functional and productive. In the end, much like the minds that gave us chemical weapons and ballistic missiles, Antonio Egas Moniz did pursue some important work whose effects are still being felt and used today. It’s just that the work he’s remembered for most wasn’t his best. Thanks for joining me for this special SciShow Infusion, especially to our Subbable subscribers, who keep these episodes coming. To learn how you can support us, just go to subbable.com to learn more. And don’t forget to go to YouTube.com/scishow and subscribe!
B2 中高級 美國腔 史上最差的諾貝爾獎 (The Worst Nobel Prize Ever Awarded) 333 14 Kana kawai 發佈於 2021 年 01 月 14 日 更多分享 分享 收藏 回報 影片單字