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 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, fire and send signals to the spinal cord and then up to the brain. Processing work gets done by cells called neurons and glia. This is your Grey matter. And brain superhighways carry information as electrical impulses from one area to another. This is your white matter. The superhighway that carries pain information from the spinal cord to the brain is our sensing pathway that ends in the cortex, a part of the brain that decides what to do with the pain signal. Another system of interconnected brain cells called the salience network 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 and enkephalins, 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 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 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 work by reducing the activity in pain-sensing circuits or boosting our coping system, or endorphins. 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 have 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 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.
假如你要用 十分钟完成这个拼图。 你会用多久完成它? 如果你的手被电击了呢? 会用更长的时间是不是? 因为痛苦让你从工作中分神。 其实,也许不是; 这取决于你如何控制疼痛。 疼痛使有些人分心, 让他们花更长的时间去完成工作, 并让他们做的没有那么好。 另外有一些人通过工作忘记疼痛, 并且他们在疼痛的时候, 比没有疼痛的时候, 工作得更快更好。 一些人可以转换思维 去转移疼痛。 为什么不同的人 在受到相同的疼痛刺激时 却感受的疼痛程度不同? 并且为什么这是有意义的呢? 首先,什么是疼痛? 疼痛是一个不愉悦的感知和情感经历, 联系到实际的或潜在的肌肉损伤。 疼痛是我们经历的东西, 所以它最接近于你所感受到的。 疼痛有强度; 你可以把它用程度表示出来 从零级没有疼痛,到十级最疼, 不过疼痛是有特点的, 比如尖锐的,缓慢的,灼烧的或心痛的。 到底是什么产生了疼痛的感觉呢? 其实,当你受伤时, 特定的肌肉疼痛感知神经细胞, 也叫伤害感受器,触动并发送信号 到脊髓再传送到大脑。 这个过程是由 神经元与神经胶质完成的。 这就是你的灰质。 并且脑路携带信息 就像电子脉冲一样 从一个区域到另一个, 这就是白质。 这个携带疼痛信息 从神经元到大脑的脑路 是我们的感觉通道 到皮质层结束, 脑部的一部分决定如何处理 疼痛信号。 另外一个相互关联的脑细胞系统 叫做巡航网络 它决定了需要注意什么。 因为疼痛可能会有严重的后果, 疼痛信号立刻激发 巡航网络。 现在,你就会注意疼痛了。 大脑也会回应疼痛 并处理这些疼痛信号。 因此,运动元神经被激发 比如说,让你把手从火炉上移开。 不过调整网络也被唤醒 去传递安多芬和脑啡肽, 在你疼痛的时候释放化学物质 或在剧烈运动时, 使运动员保持高水平。 这些化学系统帮助调节并减轻疼痛。 所有这些网络和通路互相作用 使你产生疼痛的体验, 减轻肌肉的伤害, 并帮助你处理疼痛。 每个人的系统都类似, 不过大脑循环的敏感度和效率 决定了你对疼痛的感受和如何处理疼痛。 这就是为什么有些人觉得比别人疼 为什么一些人有长期病痛 却并没有因治疗好转, 然而其他人却好了。 疼痛感受的差异性 没有比各种 对刺激的不同反应更多。 就像一些人酷爱过山车, 其他人就觉得那种剧烈移动很难受。 为什么我们疼痛的脑路差异 那么重要呢? 首先,对于不同的系统, 有许多对疼痛的治疗手段。 对于轻微的痛苦,非处方药 可以作用于导致疼痛的细胞。 其他强烈的疼痛药和麻醉剂 可作用于减轻疼痛感知回路活动 或者增强处理系统,或脑内啡。 一些人可以 用一些方法对付疼痛 比如转移注意力,休息,冥想,瑜伽, 或一些可以学到的策略, 如认知行为治疗。 对于一些遭受严重慢性疼痛的人, 那种疼痛在痊愈几个月后 都不会减轻, 常规的治疗也都不起作用。 一般来说,药物研究是 测试大量人群的结果 来判断它是否帮助了大部分的患者。 不过确实有些人 并没有从治疗中受益 或有副作用。 现在,新的治疗手段直接刺激或阻断 特定的疼痛意识或调整网络 已经被研究出来, 它针对于特定的病人, 使用像磁共振成像的工具 来绘制脑路。 研究大脑如何处理疼痛 是找到最好治疗办法的关键。 这才是真的私人治疗。