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  • 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 bedicey.

  • Like, weve 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 justwell, 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 chimpanzeesbrains 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 meaningwhite matterin latin,

  • andtomemeaning knife -- and he published these findings in 1937.

  • Monizwork 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!

Science can be .... complicated.

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最悪のノーベル賞受賞 (The Worst Nobel Prize Ever Awarded)

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    Kana kawai に公開 2021 年 01 月 14 日
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