The brain is the center of all of our thoughts, dreams, emotions, and memories.
大脑是我们所有思想、梦境、情感、记忆的中心。
It's what makes us who we are. But, there is still a lot that we don't know about the brain.
大脑决定了我们是谁。但关于大脑我们还知之甚少。
Scientists have worked for years on trying to understand the human brain
多年来，科学家们一直致力于人脑的研究，
using techniques like EEG and FMRI, where we scan the brain from the outside.
通过脑电图扫描和功能性磁共振成像技术，我们可以从外部扫描大脑。
But what if we could look inside the brains of humans and watch them as they work?
但是我们可以从内部窥探人脑的运作过程吗？
Well, now we can by looking at the brains of people who are already going through surgery for clinical reasons, like curing epilepsy.
现在，我们可以通过观察已接受过临床手术--比如治疗癫痫的病人的大脑来实现。
Epilepsy is a disease in which a faulty part of the brain starts working spontaneously for no apparent reason.
癫痫的起因是大脑的一部分出现故障，没来由地自发运作起来。
It's like an earthquake but inside your head.
就好像在你大脑里发生了一场地震。
There's no way to know in advance when a seizure will occur,
病情何时会发作我们无法提前得知，
so the patients are always at risk of unexpectedly losing control.
所以对病人而言随时都有失控的危险。
There are drugs that treat epilepsy, but these don't always work.
现在有药物可以治疗癫痫，但并不是对所有病人都有效。
Some patients who don't respond well to the drugs can undergo a different treatment where the faulty part in their brain,
那些靠药物无法改善病情的病人就要接受另一种治疗方式，
the part that starts the seizures, is surgically removed.
他们大脑里引发癫痫的部分可以通过外科手术被摘除。
The challenge is knowing which part to take out.
问题在于要摘除的究竟是哪一部分。
How do you figure out which bit of the brain is faulty?
怎样才能辨别出大脑的哪部分出了问题？
In order to find the exact location of the seizure onset,
为了找出大脑中触发癫痫的具体部位，
doctors embed electrodes directly into the patient's brain around the suspected seizure center.
医生在病人脑中可能的部位直接植入电极。
The patient then stays in the hospital for a few days,
病人需要住院几天，
waiting to have a seizure with the electrodes constantly recording the activity inside his or her brain.
等待癫痫发作，期间电极会持续不断地记录下病人脑中的活动情况。
Yes, now we want the patient to have a seizure
是的，现在我们希望病人癫痫发作，
so doctors can use the embedded electrodes to measure it and learn exactly where its origin was.
这样医生就可以通过植入的电极测量到发病根源的具体位置。

After doctors are sure where the seizures come from in the brain, they can take the electrodes out.
只要医生确定了癫痫病源位于大脑的哪一部分，就可以取出电极了。
Now they know what part of the brain they can remove in order to cure the patient.
只要摘除定位到的问题部分，即可医治病人。
These brain electrodes can tell us more than just where the seizures happen.
大脑电极能做的还不单单是告诉我们癫痫的根源。
Based on where the doctors place the electrodes in the brain, we can ask questions about what the brain does.
医生可以将电极植入大脑的任何位置，这样就能观测到大脑每一部分的功能。
Sometimes we find one cell that starts bursting in activity every time the patient sees a particular picture, for example, a picture of Marilyn Monroe.
有时候我们发现，每当一位病人看到特定的图片时，比如玛丽莲·梦露的照片，大脑中的某个细胞就开始活跃起来。
See, every time the patient sees Marilyn Monroe, some specific cells fire in the brain.
也就是说每次病人看到玛丽莲·梦露，脑中的特定细胞就会变得兴奋。
You can now know when the patient is thinking of Marilyn Monroe just by listening to these cells fire.
因此只要观察到这些细胞进入兴奋状态，就能知道病人在想玛丽莲·梦露了。
When we find one or a few of these cells with each patient, we can then do all kinds of fancy things.
现在只要我们定位了每位病人的这种细胞，就可以观察到做很多神奇的事。
For example, we can connect the recording electrode to a cursor on a screen
比如，我们将电极的另一端连接到屏幕上的光标
and have the patient move the cursor left or right just by thinking of things.
病人只需进行一些思考，光标就会跟着左右移动。
This can help people who lost the ability to move their hands,
这可以帮助失去移动双手的人，
like people with spinal cord injuries or wounded soldiers,
比如那些因脊髓损伤或在战争中受伤的人，
by having them control a prosthetic arm directly with their brain.
使他们可以直接运用大脑来控制他们的假肢。
Our brain is a brilliant device which can make predictions about the future.
我们的大脑是一台不可思议的机器，它能预测未来。
For example, we can all know which word will appear at the end of this... sentence.
比如，你能猜到我将用哪个词来结束这句...。。
The brain can solve complicated problems, imagine the entire universe, and grasp concepts such as infinity or unicorns.
大脑能解决复杂的问题，想象全宇宙的形态，掌握无穷或独角兽这些概念。
The brain produces complex emotions like love or jealousy,
大脑使人产生爱或嫉妒这样复杂的情感，
it's what makes us creative and curious, and it can even contemplate about itself.
这就使得我们拥有创造力、怀有好奇心，大脑甚至还会对其自身进行反省。
And the brain is the organ we use to study the brain.
我们利用大脑这一器官来研究大脑。
I think that the brain is the most beautiful organ in our body,
我觉得大脑是我们身上最美丽的器官。
but then I ask myself, "Which organ is making me think that?"
但我马上又问自己：“是哪个器官让我这样想的？”