Michael Dickinson: How a fly flies

311,959 views ・ 2013-02-22

TED


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00:00
Translator: Joseph Geni Reviewer: Morton Bast
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翻译人员: Hom Liu 校对人员: Li Li
00:15
I grew up watching Star Trek. I love Star Trek.
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我是看《星际迷航》长大的,我非常喜欢
00:19
Star Trek made me want to see alien creatures,
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《星际迷航》使得我很想看看外星生物
00:23
creatures from a far-distant world.
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来自很远很远的世界的生物
00:26
But basically, I figured out that I could find
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但基本上,我发现我可以
00:28
those alien creatures right on Earth.
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在地球上找到这些外星生物
00:31
And what I do is I study insects.
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我所做的就是去研究昆虫
00:34
I'm obsessed with insects, particularly insect flight.
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我对昆虫着迷,特别是昆虫的飞行
00:37
I think the evolution of insect flight is perhaps
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我认为昆虫飞行的进化,也行是
00:40
one of the most important events in the history of life.
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生命历史上一个最重要的事件
00:43
Without insects, there'd be no flowering plants.
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如果没有会飞行的昆虫,那就没有有花的植物
00:45
Without flowering plants, there would be no
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没有有花的植物,那也就没有
00:47
clever, fruit-eating primates giving TED Talks.
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聪明的,喜欢吃水果的猿长类动物在这里做TED讲座
00:50
(Laughter)
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(笑声)
00:53
Now,
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现在
00:55
David and Hidehiko and Ketaki
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David,Hidehiko和Hetaki
00:58
gave a very compelling story about
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说了一个非常吸引眼球的一个故事
01:01
the similarities between fruit flies and humans,
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关于果蝇和人类的相似性
01:04
and there are many similarities,
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相似的地方非常多
01:06
and so you might think that if humans are similar to fruit flies,
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你们觉得如果人类和果蝇很相似
01:09
the favorite behavior of a fruit fly might be this, for example --
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那么果蝇最喜欢的动作可能会是这样
01:12
(Laughter)
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(笑声)
01:15
but in my talk, I don't want to emphasize on the similarities
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但我现在不想强调这个相似性
01:18
between humans and fruit flies, but rather the differences,
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而是关注相异的地方
01:21
and focus on the behaviors that I think fruit flies excel at doing.
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关注果蝇擅长的事情
01:26
And so I want to show you a high-speed video sequence
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所以,我想让你们看一个高速录像
01:29
of a fly shot at 7,000 frames per second in infrared lighting,
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通过每秒7000帧红外拍摄的苍蝇
01:33
and to the right, off-screen, is an electronic looming predator
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在屏幕的外的右边,有一只会发电的捕食者
01:37
that is going to go at the fly.
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正在靠近这个苍蝇
01:39
The fly is going to sense this predator.
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这个苍蝇会察觉到这个捕食者
01:40
It is going to extend its legs out.
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然后会拔腿而跑
01:43
It's going to sashay away
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看似不经已地逃走
01:44
to live to fly another day.
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再活上一天
01:47
Now I have carefully cropped this sequence
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我小心地裁剪了这个片子
01:49
to be exactly the duration of a human eye blink,
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使得它跟人的眨眼时间一致
01:53
so in the time that it would take you to blink your eye,
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使得当你眨眼的时候
01:55
the fly has seen this looming predator,
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这个苍蝇已经看到了捕食者
01:59
estimated its position, initiated a motor pattern to fly it away,
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估计好了它的位置,启动了飞行模式
02:05
beating its wings at 220 times a second as it does so.
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以每秒220下的速度拍打着翅膀
02:09
I think this is a fascinating behavior
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我觉得这是个让人瞠目结舌的行为
02:11
that shows how fast the fly's brain can process information.
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这体现了苍蝇大脑处理信息的速度
02:15
Now, flight -- what does it take to fly?
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现在,我们来看航行。飞行需要什么?
02:18
Well, in order to fly, just as in a human aircraft,
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如果要飞起来,像人造航空器一样
02:21
you need wings that can generate sufficient aerodynamic forces,
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你需要能够产生足够的空气动力的翅膀
02:24
you need an engine sufficient to generate the power required for flight,
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你需要一个能够产生足够马力的引擎来支持航行
02:27
and you need a controller,
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而且你需要一个控制器
02:29
and in the first human aircraft, the controller was basically
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在人类第一个飞行器里,控制器是基本上是
02:32
the brain of Orville and Wilbur sitting in the cockpit.
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坐在座舱里的Orville和Wilbur的大脑
02:36
Now, how does this compare to a fly?
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这个跟苍蝇比较起来怎样呢?
02:39
Well, I spent a lot of my early career trying to figure out
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在我职业生涯的早期,我花了很多时间尝试弄明白
02:42
how insect wings generate enough force to keep the flies in the air.
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苍蝇的翅膀是怎样提供足够的力量使得它可以悬浮在空中
02:46
And you might have heard how engineers proved
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你也行听工程师们证明过
02:48
that bumblebees couldn't fly.
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大黄蜂不会飞
02:50
Well, the problem was in thinking that the insect wings
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问题是(他们)是用飞行器翅膀的工作原理来解释昆虫翅膀的
02:53
function in the way that aircraft wings work. But they don't.
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而实际上不是这样的
02:56
And we tackle this problem by building giant,
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为解决这个问题,我们可以制造巨大的
02:59
dynamically scaled model robot insects
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能够动态伸缩的机器昆虫模型
03:02
that would flap in giant pools of mineral oil
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它会使用大量矿物油来驱动它拍打翅膀
03:06
where we could study the aerodynamic forces.
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我们就可以从中学习空气动力学
03:08
And it turns out that the insects flap their wings
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结果是,我们发现昆虫拍打翅膀的方式
03:10
in a very clever way, at a very high angle of attack
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很巧妙。
03:13
that creates a structure at the leading edge of the wing,
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创建一个结构的机翼前沿
03:16
a little tornado-like structure called a leading edge vortex,
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称为前缘涡,有点类似龙卷风的结构
03:19
and it's that vortex that actually enables the wings
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这个漩涡实际上让翅膀
03:22
to make enough force for the animal to stay in the air.
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可以产生足够的力量让它们悬浮在空中
03:25
But the thing that's actually most -- so, what's fascinating
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但最让人着迷的
03:28
is not so much that the wing has some interesting morphology.
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不是翅膀那有趣的形态学
03:31
What's clever is the way the fly flaps it,
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最聪明的是苍蝇拍打翅膀的方式
03:34
which of course ultimately is controlled by the nervous system,
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它最终还是受控与神经系统
03:38
and this is what enables flies to perform
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这使得苍蝇可以完成
03:40
these remarkable aerial maneuvers.
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这些让人叹绝的空中杂技
03:43
Now, what about the engine?
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那么,这个引擎怎样呢?
03:45
The engine of the fly is absolutely fascinating.
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苍蝇的引擎绝对让人着迷
03:48
They have two types of flight muscle:
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它们有两种用于航行的肌肉
03:50
so-called power muscle, which is stretch-activated,
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所谓的力量型肌肉,这是舒张时激活的
03:53
which means that it activates itself and does not need to be controlled
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这意味着它自己激活自己,并不需要被控制于
03:56
on a contraction-by-contraction basis by the nervous system.
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一个基于收缩的中枢神经系统
04:00
It's specialized to generate the enormous power required for flight,
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它有专门来生成所需的飞行的巨大的力量
04:04
and it fills the middle portion of the fly,
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它填充着中间的部分
04:06
so when a fly hits your windshield,
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所以,当一只苍蝇撞到你的挡风玻璃,
04:08
it's basically the power muscle that you're looking at.
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你看到的基本上它的力量型肌肉
04:10
But attached to the base of the wing
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但附加到机翼的基部
04:12
is a set of little, tiny control muscles
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是一套的小型的控制肌肉
04:15
that are not very powerful at all, but they're very fast,
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这不是非常强大,但他们速度非常快,
04:18
and they're able to reconfigure the hinge of the wing
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他们就能够重新配置的机翼转轴
04:22
on a stroke-by-stroke basis,
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不断拍打的着
04:23
and this is what enables the fly to change its wing
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这使苍蝇能够改变它的翅膀
04:26
and generate the changes in aerodynamic forces
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并在产生在气动力学上的变化
04:29
which change its flight trajectory.
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这改变其飞行轨迹
04:32
And of course, the role of the nervous system is to control all this.
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当然,中枢神经系统的作用是控制所有这一切
04:36
So let's look at the controller.
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现在,让我们看看该控制器
04:37
Now flies excel in the sorts of sensors
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现在苍蝇擅长各种传感器
04:40
that they carry to this problem.
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他们引出这一问题
04:42
They have antennae that sense odors and detect wind detection.
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它们身上有天线,能够感觉气味和检测风向
04:46
They have a sophisticated eye which is
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他们的复眼
04:48
the fastest visual system on the planet.
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是这个星球上最快的视觉系统
04:50
They have another set of eyes on the top of their head.
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它们头上有另一套眼睛。
04:52
We have no idea what they do.
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我们也不知道它们用来做什么
04:54
They have sensors on their wing.
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它们在翼上也有传感器
04:57
Their wing is covered with sensors, including sensors
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其机翼上都是传感器,包括一些
05:01
that sense deformation of the wing.
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感觉机翼形变的传感器
05:03
They can even taste with their wings.
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它们甚至可以用它们的翅膀分辨味道
05:05
One of the most sophisticated sensors a fly has
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苍蝇最复杂的传感器之一
05:08
is a structure called the halteres.
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是一种结构被称为笼头。
05:10
The halteres are actually gyroscopes.
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笼头其实是陀螺仪。
05:11
These devices beat back and forth about 200 hertz during flight,
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在飞行中,这些设备以约 200 赫兹振动着
05:16
and the animal can use them to sense its body rotation
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可以使用它们来感受其身体的旋转
05:19
and initiate very, very fast corrective maneuvers.
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并启动非常非常快速的纠正动作。
05:23
But all of this sensory information has to be processed
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但所有这些感官信息需要由一个大脑来处理
05:25
by a brain, and yes, indeed, flies have a brain,
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事实上,苍蝇有一个大脑
05:29
a brain of about 100,000 neurons.
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脑内神经元约 100,000个
05:32
Now several people at this conference
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现在在这个会议的一些人
05:34
have already suggested that fruit flies could serve neuroscience
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已经提议果蝇可帮助神经科学
05:39
because they're a simple model of brain function.
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因为它们是大脑功能的简单模型
05:42
And the basic punchline of my talk is,
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我基本的观点就是
05:44
I'd like to turn that over on its head.
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我想关注在它的头上
05:47
I don't think they're a simple model of anything.
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我并不认为它们是一个什么简单的模型
05:49
And I think that flies are a great model.
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我认为苍蝇是一个伟大的模型
05:52
They're a great model for flies.
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它们是苍蝇的伟大的模型
05:54
(Laughter)
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(笑声)
05:57
And let's explore this notion of simplicity.
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并让我们研究一下这种简单性
06:00
So I think, unfortunately, a lot of neuroscientists,
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所以我认为,不幸的是,大量的神经学家
06:02
we're all somewhat narcissistic.
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我们都有些自恋
06:04
When we think of brain, we of course imagine our own brain.
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当我们想到大脑时,我们当然想到的是我们自己的大脑
06:08
But remember that this kind of brain,
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但请记住到这种大脑
06:09
which is much, much smaller
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这是小的很多的
06:11
— instead of 100 billion neurons, it has 100,000 neurons —
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没有 1000 个亿神经元,它有 100,000 个神经元 — —
06:14
but this is the most common form of brain on the planet
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但这是大脑在这个星球上最常见的形式
06:17
and has been for 400 million years.
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它存在了4 亿年
06:20
And is it fair to say that it's simple?
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这可以说它很简单吗?
06:22
Well, it's simple in the sense that it has fewer neurons,
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在某种意义上说这是比较简单的,因为它有较少的神经元
06:24
but is that a fair metric?
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但是这是一个公平的指标吗?
06:26
And I would propose it's not a fair metric.
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我不觉得它是一个公平的指标
06:28
So let's sort of think about this. I think we have to compare --
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现在,让我们随便想想。我认为我们必须进行比较
06:31
(Laughter) —
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(笑声)
06:33
we have to compare the size of the brain
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我们要比较下大脑的大小
06:38
with what the brain can do.
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比较下大脑可以做什么
06:40
So I propose we have a Trump number,
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所以我建议我们用一个Trump号
06:43
and the Trump number is the ratio of this man's
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Trump号是这个人的比例
06:46
behavioral repertoire to the number of neurons in his brain.
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由他的行为除以他大脑中神经元的数目得出
06:49
We'll calculate the Trump number for the fruit fly.
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我们会计算出实蝇的Trump号
06:52
Now, how many people here think the Trump number
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现在,在这里有多少人觉得Trump号
06:55
is higher for the fruit fly?
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比实蝇的要高?
06:57
(Applause)
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(掌声)
07:00
It's a very smart, smart audience.
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观众们都很聪明
07:03
Yes, the inequality goes in this direction, or I would posit it.
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不平等是朝着这个方向走的,或者让我推断下
07:06
Now I realize that it is a little bit absurd
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现在认识到它是有点荒谬
07:09
to compare the behavioral repertoire of a human to a fly.
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要比较人和苍蝇的行为
07:12
But let's take another animal just as an example. Here's a mouse.
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但让我们来看另一种动物,只是作为一个例子。这是一只老鼠
07:16
A mouse has about 1,000 times as many neurons as a fly.
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老鼠比苍蝇有约 1,000 倍多的神经元
07:21
I used to study mice. When I studied mice,
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我以前研究老鼠。当我研究老鼠的时候
07:23
I used to talk really slowly.
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我说话真的很慢
07:26
And then something happened when I started to work on flies.
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然后当我开始研究苍蝇的时候发生了一些状况
07:28
(Laughter)
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(笑声)
07:31
And I think if you compare the natural history of flies and mice,
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我觉得如果你比较苍蝇和老鼠的自然史
07:34
it's really comparable. They have to forage for food.
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它是可比的。它们得去觅食
07:37
They have to engage in courtship.
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它们不得不求爱
07:40
They have sex. They hide from predators.
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它们要发生性关系。它们要躲避捕食者
07:43
They do a lot of the similar things.
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它们做了很多类似的事情
07:45
But I would argue that flies do more.
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但我想说苍蝇做更多
07:47
So for example, I'm going to show you a sequence,
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例如,我要向您展示一个影片
07:50
and I have to say, some of my funding comes from the military,
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我不得不说,我的一些资金来自军方
07:55
so I'm showing this classified sequence
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因此,我将展示这个机密影片
07:57
and you cannot discuss it outside of this room. Okay?
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你不能在外面讨论这个。好吗?
08:01
So I want you to look at the payload
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我想让你你看这个载荷
08:03
at the tail of the fruit fly.
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在果蝇的尾巴上
08:06
Watch it very closely,
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仔细看好了
08:08
and you'll see why my six-year-old son
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你将看到为什么我的六岁儿子
08:12
now wants to be a neuroscientist.
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现在想要一个神经学家
08:17
Wait for it.
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等待下
08:18
Pshhew.
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噗噗
08:20
So at least you'll admit that if fruit flies are not as clever as mice,
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所以至少你得承认,如果果蝇灭有老鼠聪明
08:23
they're at least as clever as pigeons. (Laughter)
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它们至少和鸽子一样聪明。(笑声)
08:28
Now, I want to get across that it's not just a matter of numbers
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现在,我想要传达的并不只是数字
08:32
but also the challenge for a fly to compute
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而且是苍蝇面临的计算上的挑战
08:34
everything its brain has to compute with such tiny neurons.
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一切都得靠它的大脑,而却只有很少的的神经元
08:37
So this is a beautiful image of a visual interneuron from a mouse
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这就是老鼠的中间神经元的美丽图片
08:40
that came from Jeff Lichtman's lab,
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那是来自Jeff Lichtman的实验室
08:43
and you can see the wonderful images of brains
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你可以看到大脑的精彩画面
08:46
that he showed in his talk.
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他在他的研究种展示过
08:49
But up in the corner, in the right corner, you'll see,
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但在右上角,你看
08:52
at the same scale, a visual interneuron from a fly.
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在相同的比例下,从苍蝇的中间神经元的图像
08:56
And I'll expand this up.
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我就会放大这个图像
08:58
And it's a beautifully complex neuron.
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它是一个精美复杂的神经元
09:00
It's just very, very tiny, and there's lots of biophysical challenges
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它非常非常的小,尝试用这些极为微小的神经元来计算
09:03
with trying to compute information with tiny, tiny neurons.
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充满了大量的生物物理挑战
09:07
How small can neurons get? Well, look at this interesting insect.
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神经元能有多小?那么,来看看这个有趣的昆虫
09:10
It looks sort of like a fly. It has wings, it has eyes,
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它看起来像一只苍蝇。它有翅膀,眼睛
09:13
it has antennae, its legs, complicated life history,
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它有天线,双腿,复杂的生活史,
09:15
it's a parasite, it has to fly around and find caterpillars
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它是一种寄生虫,它得在周围飞,找毛毛虫
09:18
to parasatize,
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然后在上面寄生,
09:20
but not only is its brain the size of a salt grain,
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不仅仅它的大脑只有盐粒大小
09:24
which is comparable for a fruit fly,
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跟果蝇相当
09:26
it is the size of a salt grain.
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它只有一盐粒的大小
09:29
So here's some other organisms at the similar scale.
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这里有类似规模的生物组织
09:32
This animal is the size of a paramecium and an amoeba,
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这个动物跟草履虫和变形虫中大小相当
09:37
and it has a brain of 7,000 neurons that's so small --
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它有一个有7,000 个神经元的大脑,是太小了
09:40
you know these things called cell bodies you've been hearing about,
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你应该知道这些叫做细胞体的东西
09:43
where the nucleus of the neuron is?
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神经元的核心在哪里?
09:45
This animal gets rid of them because they take up too much space.
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这种动物去掉了它们,因为它们占用太多空间
09:48
So this is a session on frontiers in neuroscience.
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这是一个神经科学的前沿的会议
09:51
I would posit that one frontier in neuroscience is to figure out how the brain of that thing works.
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我会认为这一神经科学前沿的研究是要找出大脑是如何工作的
09:56
But let's think about this. How can you make a small number of neurons do a lot?
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但让我们想一想。怎样可以使少量的神经元能做很多事情?
10:02
And I think, from an engineering perspective,
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我认为,从工程的角度看
10:04
you think of multiplexing.
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你会想到多路复用
10:06
You can take a hardware and have that hardware
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您可以用硬件,并用该硬件
10:08
do different things at different times,
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在不同的时间做不同的事情
10:10
or have different parts of the hardware doing different things.
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或者用不同部分的硬件做不同的事情
10:13
And these are the two concepts I'd like to explore.
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我想要探讨这两个概念
10:16
And they're not concepts that I've come up with,
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这些都不是我自己想出来的概念
10:18
but concepts that have been proposed by others in the past.
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但在过去由其他人提出的概念
10:23
And one idea comes from lessons from chewing crabs.
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一个来自于咀嚼螃蟹的想法
10:26
And I don't mean chewing the crabs.
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我不是指咀嚼螃蟹
10:27
I grew up in Baltimore, and I chew crabs very, very well.
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我在巴尔的摩长大,我非常会咀嚼螃蟹
10:31
But I'm talking about the crabs actually doing the chewing.
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但我说的是蟹咀的咀嚼行为
10:34
Crab chewing is actually really fascinating.
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蟹咀的咀嚼行为其实真的令人着迷
10:36
Crabs have this complicated structure under their carapace
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螃蟹在甲壳下有复杂的结构
10:39
called the gastric mill
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称为胃磨机
10:41
that grinds their food in a variety of different ways.
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以各种不同方式在磨它们的食物
10:43
And here's an endoscopic movie of this structure.
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这里是用内镜拍的电影
10:48
The amazing thing about this is that it's controlled
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令人惊异的是它受控于
10:51
by a really tiny set of neurons, about two dozen neurons
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由约有 20 多个神经元很小的神经元集
10:54
that can produce a vast variety of different motor patterns,
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可产生多种不同的运动模式
10:59
and the reason it can do this is that this little tiny ganglion
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它可以这样做的原因是,这个小小的神经节
11:04
in the crab is actually inundated by many, many neuromodulators.
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实际上螃蟹密布着许多的神经调质
11:08
You heard about neuromodulators earlier.
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你早前听说过神经调质
11:10
There are more neuromodulators
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有更多的神经调质
11:12
that alter, that innervate this structure than actually neurons in the structure,
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实际上比神经元在这个结构上分布得更多
11:18
and they're able to generate a complicated set of patterns.
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它们能够生成一组复杂的模式
11:22
And this is the work by Eve Marder and her many colleagues
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这是Eve Marder和她的许多同事的工作成果
11:25
who've been studying this fascinating system
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他们一直在研究这个有趣的系统
11:28
that show how a smaller cluster of neurons
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这展示了神经元小群集怎样
11:30
can do many, many, many things
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可以做很多、 很多、 很多的事情
11:32
because of neuromodulation that can take place on a moment-by-moment basis.
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因为神经调节能时刻进行
11:36
So this is basically multiplexing in time.
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所以这基本上复用的时间
11:39
Imagine a network of neurons with one neuromodulator.
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想象一个神经元与一个神经调质构成的网络
11:42
You select one set of cells to perform one sort of behavior,
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你选择一组细胞来执行一种行为
11:45
another neuromodulator, another set of cells,
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另一个神经调质,另一组细胞
11:48
a different pattern, and you can imagine
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不同的模式,你可以想象
11:49
you could extrapolate to a very, very complicated system.
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你可以推出一个非常、 非常复杂的系统
11:53
Is there any evidence that flies do this?
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是否有任何证据表明苍蝇这样做吗?
11:55
Well, for many years in my laboratory and other laboratories around the world,
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在我的实验室和其他世界各地的实验室
11:59
we've been studying fly behaviors in little flight simulators.
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我们就一直在小飞行模拟器中研究苍蝇的行为
12:01
You can tether a fly to a little stick.
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你可以把苍蝇系在一个小棒上
12:03
You can measure the aerodynamic forces it's creating.
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你可以测量它产生的空气动力
12:06
You can let the fly play a little video game
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你可以让玩苍蝇玩一个小视频游戏
12:08
by letting it fly around in a visual display.
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让它在显示器周围飞
12:12
So let me show you a little tiny sequence of this.
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我让你们看看一个小片段
12:14
Here's a fly
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这是一只苍蝇
12:16
and a large infrared view of the fly in the flight simulator,
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和一个苍蝇飞行模拟器的大型红外图像
12:19
and this is a game the flies love to play.
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这是苍蝇喜欢玩的游戏
12:21
You allow them to steer towards the little stripe,
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让它们导向到这个小条纹
12:23
and they'll just steer towards that stripe forever.
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它们会永远引向该带区
12:26
It's part of their visual guidance system.
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这是它的视觉导航系统的一部分
12:30
But very, very recently, it's been possible
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但非常,非常的最近
12:32
to modify these sorts of behavioral arenas for physiologies.
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有可能为生理学而改变这种行为研究场所
12:37
So this is the preparation that one of my former post-docs,
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这些准备,是由我之前一个博士后
12:40
Gaby Maimon, who's now at Rockefeller, developed,
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叫Gaby Maimon开放的,他现在在洛克菲勒
12:42
and it's basically a flight simulator
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这基本上是一种飞行模拟器
12:44
but under conditions where you actually can stick an electrode
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但你可以把电极插在
12:47
in the brain of the fly and record
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苍蝇的脑内
12:49
from a genetically identified neuron in the fly's brain.
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通过苍蝇大脑中用基因标示过的神经元做记录
12:53
And this is what one of these experiments looks like.
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这是这些实验的样子
12:55
It was a sequence taken from another post-doc in the lab,
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它是从一个博士后实验室中拍摄的
12:58
Bettina Schnell.
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叫Bettina Schenell
12:59
The green trace at the bottom is the membrane potential
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在底部的绿色踪迹是膜电位
13:03
of a neuron in the fly's brain,
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来自苍蝇脑内的神经元
13:05
and you'll see the fly start to fly, and the fly is actually
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你将看到苍蝇开始飞翔,它其实是
13:08
controlling the rotation of that visual pattern itself
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自己控制着这种视觉模式的旋转
13:11
by its own wing motion,
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由其自身翼的运动
13:12
and you can see this visual interneuron
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你可以看到这个视觉神经
13:14
respond to the pattern of wing motion as the fly flies.
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在苍蝇飞行中对翼的运动做出的反应
13:18
So for the first time we've actually been able to record
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我们实际上第一次能够记录
13:21
from neurons in the fly's brain while the fly
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通过苍蝇的脑内神经元
13:24
is performing sophisticated behaviors such as flight.
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而且这个苍蝇还在执行复杂的行为,如飞行。
13:28
And one of the lessons we've been learning
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我们一直在学习的经验教训之一
13:30
is that the physiology of cells that we've been studying
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就是我们一直在研究的细胞的生理学
13:32
for many years in quiescent flies
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多年来在静止的苍蝇上
13:35
is not the same as the physiology of those cells
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与这些细胞生理学并不相同的是
13:37
when the flies actually engage in active behaviors
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这是在当苍蝇处于运动状态下
13:40
like flying and walking and so forth.
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比较飞行中和行走中等等。
13:43
And why is the physiology different?
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为什么生理学上不同呢?
13:46
Well it turns out it's these neuromodulators,
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事实是这些神经调质
13:48
just like the neuromodulators in that little tiny ganglion in the crabs.
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就像这小螃蟹的神经节调质
13:52
So here's a picture of the octopamine system.
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这里是章鱼胺系统的图片
13:54
Octopamine is a neuromodulator
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章鱼胺上,神经调质
13:56
that seems to play an important role in flight and other behaviors.
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似乎在飞行和其他行为具有重要的作用
14:00
But this is just one of many neuromodulators
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但这只是许多调质
14:03
that's in the fly's brain.
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这是在苍蝇的大脑中
14:04
So I really think that, as we learn more,
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所以我真的认为,当我们了解的更多
14:06
it's going to turn out that the whole fly brain
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结果将是,整个苍蝇的大脑
14:09
is just like a large version of this stomatogastric ganglion,
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就像这胃肠神经节的大版本
14:12
and that's one of the reasons why it can do so much with so few neurons.
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这就是为什么它可以做这么多事情却只有这么少的神经元的原因之一
14:16
Now, another idea, another way of multiplexing
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现在,另一个想法,另一种方式的多路复用
14:19
is multiplexing in space,
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是空间多路复用
14:21
having different parts of a neuron
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用神经元的不同部分
14:23
do different things at the same time.
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在同一时间做不同的事情
14:25
So here's two sort of canonical neurons
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所以这里是典型的神经元的两个类型
14:27
from a vertebrate and an invertebrate,
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从脊椎动物和无脊椎动物,
14:29
a human pyramidal neuron from Ramon y Cajal,
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Ramon Y Cajal(拉孟伊卡哈)的一个人类锥体神经元
14:32
and another cell to the right, a non-spiking interneuron,
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和另一个右侧的细胞,非尖状的中间神经元
14:36
and this is the work of Alan Watson and Malcolm Burrows many years ago,
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这是很多年前,Alan Waston和Malcolm Burrows的工作成果
14:40
and Malcolm Burrows came up with a pretty interesting idea
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Malcolm Burrows想出了一个很有趣的想法
14:43
based on the fact that this neuron from a locust
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基于一个事实,就是蝗虫的神经元
14:46
does not fire action potentials.
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不会触发动作电位
14:48
It's a non-spiking cell.
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它是一个非尖状的细胞
14:50
So a typical cell, like the neurons in our brain,
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所以一个典型的细胞,像我们的大脑中的神经元
14:53
has a region called the dendrites that receives input,
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具有称为树突的区域来接收输入
14:55
and that input sums together
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并把输入累加在一起
14:58
and will produce action potentials
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并将产生动作电位
15:00
that run down the axon and then activate
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跑到轴突下,然后激活
15:03
all the output regions of the neuron.
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所有输出区域的神经元
15:05
But non-spiking neurons are actually quite complicated
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但是非尖状神经元其实相当复杂
15:08
because they can have input synapses and output synapses
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因为它们有神经输突触入和输出突触
15:11
all interdigitated, and there's no single action potential
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都是整合好的,没有单一的动作电位
15:15
that drives all the outputs at the same time.
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在同一时间驱动所有输出
15:18
So there's a possibility that you have computational compartments
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所以有可能有个计算单元
15:22
that allow the different parts of the neuron
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使得神经元的不同部分
15:26
to do different things at the same time.
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在同一时间做不同的事情
15:28
So these basic concepts of multitasking in time
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这些是多任务处理的基本概念
15:33
and multitasking in space,
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在时间和空间,在多任务处理
15:35
I think these are things that are true in our brains as well,
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我认为这些是在我们的大脑里面是一样的
15:38
but I think the insects are the true masters of this.
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但我认为昆虫是真正掌握要领的
15:41
So I hope you think of insects a little bit differently next time,
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因此,我希望下次你会觉得昆虫有点不同
15:44
and as I say up here, please think before you swat.
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而正如我在这里所说,请在拍死它们之前再三想想
15:47
(Applause)
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(掌声)
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