Q-Eng

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一部、専門用語があるが、全体としてはアニメの助けもあり判りやすい。
「痛みの感知の仕組み」 の良い勉強になる。 不快な画面はない。　　　　　　　

易　　05分・・160wpm　　2014/11/20 新出

字幕：上の動画は開始後 で字幕On/Off､ で言語選択。文字ｻｲｽﾞはｵﾌﾟｼｮﾝから｡
　　　　動画を見るとき、パソコンで画面全体を拡大するときれい。

★下記英文はマウスオーバー辞書が使えます｡　　　　　　　 　　　　

Let's say that it would take you ten minutes to solve this puzzle. How long would it take if you received constant electric shocks to your hands? Longer, right? Because the pain would distract you from the task. Well, maybe not; it depends on how you handle pain.

Some people are distracted by pain. It takes them longer to complete a task, and they do it less well. Other people use tasks to distract themselves from pain, and those people actually do the task faster and better when they're in pain than when they're not.

Some people can just send their mind wandering to distract themselves from pain. How can different people be subjected to the exact same painful stimulus and yet experience the pain so differently? And why does this matter?

First of all, what is pain? Pain is an unpleasant sensory and emotional experience, associated with actual or potential tissue（組織）damage. Pain is something we experience, so it's best measured by what you say it is. Pain has an intensity; you can describe it on a scale from zero, no pain, to ten, the most pain imaginable.

But pain also has a character, like sharp, dull, burning, or aching. 　What exactly creates these perceptions of pain? 　Well, when you get hurt, special tissue damage-sensing nerve cells, called nociceptors（侵害受容器）, fire and send signals to the spinal cord（脊髄） and then up to the brain. Processing work gets done by cells called neurons and glial（ﾆｭｰﾛﾝとｸﾞﾘｱ）. This is your grey matter（灰白質）.
　（neuron：ﾆｭｰﾛﾝ､神経細胞　　glial：ｸﾞﾘｱ､膠コウ細胞＝ﾆｭ-ﾛﾝ以外の総称　 　膠 にかわ）
　（grey matter：灰白質=神経細胞の集まり、大脳･小脳の皮質部、脊髄のH型中央部)　
　　
And brain superhighways carry information as electrical impulses from one area to another. This is your white matter（白質）. The superhighway that carries pain information from the spinal cord to the brain is our sensing pathway that ends in the cortex（大脳皮質）, a part of the brain that decides what to do with the pain signal.
　（white matter：白質=神経線維の集まり、大脳・小脳の深部、脊髄の表層部）

Another system of interconnected brain cells called the salience network（顕著性ﾈｯﾄﾜｰｸ） decides what to pay attention to. Since pain can have serious consequences, the pain signal immediately activates the salience network. Now, you're paying attention.

The brain also responds to the pain and has to cope with these pain signals. So, motor pathways are activated to take your hand off a hot stove, for example. But modulation networks are also activated that deliver endorphins（ｴﾝﾄﾞﾙﾌｨﾝ） and enkephalins（ｴﾝｹﾌｧﾘﾝ）, chemicals released when you're in pain or during extreme exercise, creating the runner's high. These chemical systems help regulate and reduce pain.

All these networks and pathways work together to create your pain experience, to prevent further tissue damage, and help you to cope with pain. This system is similar for everyone, but the sensitivity and efficacy（効率性）of these brain circuits determines how much you feel and cope with pain. This is why some people have greater pain than others and why some develop chronic（慢性の）pain that does not respond to treatment, while others respond well.

Variability in pain sensitivities is not so different than all kinds of variability in responses to other stimuli. Like how some people love roller coasters, but other people suffer from terrible motion sickness. Why does it matter that there is variability in our pain brain circuits?

Well, there are many treatments for pain, targeting different systems. For mild pain, non-prescription medications can act on cells where the pain signals start. Other stronger pain medicines and anesthetics（麻酔薬） work by reducing the activity in pain-sensing circuits or boosting our coping system, or endoprhins. Some people can cope with pain using methods that involve distraction, relaxation, meditation, yoga, or strategies that can be taught, like cognitive behavioral therapy.

For some people who suffer from severe chronic pain, that is pain that doesn't go away months after their injury should've healed, none of the regular treatments work. Traditionally, medical science has been about testing treatments on large groups to determine what would help a majority of patients. But this has usually left out some who didn't benefit from the treatment or experienced side effects.

Now, new treatments that directly stimulate or block certain pain-sensing attention or modulation networks are being developed, along with ways to tailor them to individual patients, using tools like magnetic resonance imaging（MRI 磁気共鳴画像）to map brain pathways. Figuring out how your brain responds to pain is the key to finding the best treatment for you. That's true personalized medicine.