By mapping out where cannabinoid receptors exist in the brain, and in what density,
通过了解大脑中存在的大麻素受体的位置及疏密情况，
it should help shed light on the role of the cannabinoid system, which scientists are only just beginning to understand.
能帮助科学家揭开大麻素系统之谜。对于大麻素系统的认识，科学家们才刚刚起步。
What would you say the function is of these endo-cannabinoid chemicals?
你认为这些内源性大麻素有什么作用？
Well, they act like a dimmer switch for other neurotransmitters.
它们是其他神经传递素的调节器。
So other neutotransmitters like dopamine, where they're released in large quantities, you need to have a way to turn down that signal, sort of turn down the amount of neurotransmitter released.
如多巴胺之类的神经传递素释放过多时，你需要减少那种信号的传递，也就是降低信息传递素的释放量。
Why do these other chemical messengers need regulating?
为什么要调节这些化学信使呢？
That's a good question.
这个问题问得好。
If you have too much of a signal, it can actually be toxic to some brain cells.
如果你接收一种信号过多，一些脑细胞就会因此受损。
Imagine the case in epilepsy.
癫痫症就是这样的。
A lot of message is getting across, it's not being regulated.
大量的信息不停通过，而它们均未经调节，
It's all garbled, it's being sent all at once, in full force.
完全扭曲，并且一齐释放，毫无约束。
In cases such as epilepsy, too much of a neurotransmitter is released,
癫痫症，就是由于过多的神经传递素被释放，
flooding through the brain and activating too many nerve cells.
它们淹没了整个大脑，刺激了大量的神经细胞导致的。
But when the cannabinoid receptors are activated, they cause the nerve cells to reduce the amount of neurotransmitter they release.
当大麻素受体被激活，它们促使神经细胞的神经传递素释放量减少。
In this way, the cannabinoid system keeps the brain stable, with levels of neurotransmitters at a happy medium.
这样，大麻素系统让神经传递素停留在折中的水平，以此维持大脑的稳定。
After five hours, the scan is complete.
5个小时之后，扫描完成了。
So Garth, you've got the results in?
加斯，你得到结果了吗？
Yes, we finished our five-hour scan and let me show you what we have.
是的，5小时的扫描完成了，让我给你展示下结果。
So this is an image from our subject from today.
这就是今天扫描得到的图像。
The receptors are highlighted in what colour?
这些大麻素受体是用什么颜色标注的呢？
In bright red.
鲜红色。
Well, any colour you see, there are receptors, and red is the really dense areas, and you can see there's a lot of red and yellow.
其实你看到有颜色的地方都是受体，红色代表的是密度高的地方，你看到红色和黄色的部分有很多。
Green and blue are the really not dense areas, where there are not many receptors.
绿色和蓝色指示密度较低的地方。
Incredible.
真不可思议。
So they really are everywhere?
也就是说，大麻素受体遍布了整个大脑。
Yes, yes.
是的。
