ABOUT THE SPEAKERS
Steve Ramirez - Neuroscientist
When Steve Ramirez published his latest study in Science, it caused a media frenzy. Why? Because the paper was on implanting false memories in the brains of mice.

Why you should listen

Steve is a graduate student at MIT’s Brain and Cognitive Sciences department pursuing a Ph.D. in neuroscience. His work focuses on finding where single memories are located throughout the brain, genetically tricking the brain cells that house these memories to respond to brief pulses of light, and then using these same flickers of light to reactivate, erase and implant memories. The goals of his research are twofold: to figure out how the brain gives rise to the seemingly ephemeral process of memory, and to predict what happens when specific brain pieces breakdown to impair cognition. His work has been published in Science and covered by New Scientist, Discover, Scientific American, and Gizmodo.

Ramirez aims to be a professor who runs a lab that plucks questions from the tree of science fiction to ground them in experimental reality. He believes that a team-oriented approach to science makes research and teaching far more exciting. When he’s not tinkering with memories in the lab, Ramirez also enjoys running and cheering on every sports team in the city of Boston.

More profile about the speaker
Steve Ramirez | Speaker | TED.com
Xu Liu - Neuroscientist
In his groundbreaking work, Xu Liu investigated how to activate and deactivate specific memories in mice.

Why you should listen

During his PhD, Xu Liu studied the mechanisms of learning and memory, using fruit flies as a model system. By changing the expression of certain genes in the fly brain, he generated smart flies that can learn many times faster than their peers. Using live imaging, he also detected learning-induced changes in the brain cells and observed memory formation inside the brain with light.

After graduation, he moved to MIT and joined Dr. Susumu Tonegawa's lab as a postdoctoral associate. He continued his pursuit of memory with light there. Instead of just watching memory formation, he developed a system in mice where one can not only identify and label cells in the brain for a particular memory, but also turn these cells on and off with light to activate this memory at will. This work was published in Science and has been covered by the media worldwide. Liu passed away in February 2015.

More profile about the speaker
Xu Liu | Speaker | TED.com
TEDxBoston

Steve Ramirez and Xu Liu: A mouse. A laser beam. A manipulated memory.

史蒂夫 ‧ 拉米雷斯、劉旭: 一隻老鼠,一束激光,一個可以操控嘅記憶

Filmed:
1,127,889 views

記憶係咪可以編輯嘅呢? 呢個係科幻問題,亦係史蒂夫同劉旭兩位麻省理工科學家所提出嘅。 實際上,佢哋可以將激光照入一個活老鼠嘅大腦,去啟動同操控老鼠嘅記憶。 喺呢個娛樂色彩豐富嘅演講裏面,佢哋分享佢哋係點樣做到,同埋更重要,點解要做咁嘅事。
- Neuroscientist
When Steve Ramirez published his latest study in Science, it caused a media frenzy. Why? Because the paper was on implanting false memories in the brains of mice. Full bio - Neuroscientist
In his groundbreaking work, Xu Liu investigated how to activate and deactivate specific memories in mice. Full bio

Double-click the English transcript below to play the video.

00:12
Steve史蒂夫 Ramirez拉米雷斯: My first year of grad畢業 school學校,
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史:諗返我研究生第一年
00:13
I found發現 myself自己 in my bedroom睡房
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當時我攤喺床,食好多班傑利雪糕
00:15
eating lots of Ben & Jerry's杰瑞嘅
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睇無聊電視
00:18
watching some trashy冇用 TV電視
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00:19
and maybe, maybe listening to Taylor泰勒 Swift迅速.
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或者聽 Taylor Swift 嘅歌
00:23
I had just gone through透過 a breakup分手.
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嗰時我啱啱分咗手
00:24
(Laughter笑聲)
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(笑聲)
00:26
So for the longest time, all I would do
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所以,第一次長時間
00:28
is recall記得 the memory記憶 of this person over and over again,
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我喺度不斷回憶關於呢個人
00:32
wishing希望 that I could get rid擺脫 of that gut-wrenching痛苦的折磨,
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我希望能夠擺脫呢種自我苦惱
內臟似俾掏空一樣嘅感覺
00:34
visceral內臟 "blah等陣" feeling感覺.
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00:37
Now, as it turns輪流 out, I'm a neuroscientist神經,
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宜家,我係神經生物學家
00:39
so I knew that the memory記憶 of that person
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因此我知道對舊情人嘅記憶
同記憶中唔舒服嘅感覺
00:42
and the awful可怕, emotional情感 undertones意味 that color顏色 in that memory記憶,
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00:45
are largely主要 mediated介導 by separate單獨 brain大腦 systems系統.
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大部分係由兩個唔同嘅腦部系統所介導
00:47
And so I thought, what if we could go into the brain大腦
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所以,我喺度諗
如果我哋可以進入大腦
00:50
and edit編輯 out that nauseating令人作嘔 feeling感覺
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剪走嗰種令人作嘔嘅感覺
00:52
but while keeping保持 the memory記憶 of that person intact完整?
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但仍然保持對舊情人嘅完整記憶
咁會點?
00:55
Then I realized實現, maybe that's a little bit lofty崇高 for now.
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然後我認識到,呢個諗法
目前嚟講仲係做唔到
00:57
So what if we could start初時 off by going into the brain大腦
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咁我哋係咪可以
由進入大腦、尋找單一記憶著手?
01:00
and just finding發現 a single memory記憶 to begin初時 with?
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01:03
Could we jump-start跳转開始 that memory記憶 back to life,
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我哋可唔可以將記憶帶返嚟現實生活
01:05
maybe even play with the contents內容 of that memory記憶?
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甚至操作記憶?
01:09
All that said, there is one person in the entire整個 world世界 right now
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但到呢一刻
我真心希望一個人冇睇到呢場演講
01:11
that I really hope希望 is not watching this talk.
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01:13
(Laughter笑聲)
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(笑聲)
01:17
So there is a catch抓住. There is a catch抓住.
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所以大家要留意返
01:20
These ideas想法 probably可能 remind you of "Total Recall記得,"
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呢啲諗法或者令你哋諗起
電影《全面回憶》
01:23
"Eternal永恒 Sunshine陽光 of the Spotless一塵不染 Mind介意,"
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《暖暖內含光》
01:25
or of "Inception初始."
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或者《盜夢空間》
01:27
But the movie電影 stars星星 that we work with
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但同我哋實驗室合作嘅明星
位位都係星光熠熠
01:28
are the celebrities名人 of the lab實驗室.
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劉:佢哋就係實驗室老鼠
01:30
Xu Liu: Test測試 mice小鼠.
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(笑聲)
01:32
(Laughter笑聲)
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01:33
As neuroscientists神經, we work in the lab實驗室 with mice小鼠
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身為神經生物學家
我哋喺實驗室用老鼠
睇下記憶點樣運作
01:36
trying試圖 to understand理解 how memory記憶 works工程.
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01:40
And today今日, we hope希望 to convince說服 you that now
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今日,我哋希望令你相信
01:42
we are actually講真 able to activate激活 a memory記憶 in the brain大腦
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宜家我哋能夠以光速啟動大腦嘅記憶
01:45
at the speed速度 of light.
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為咗令你哋相信
01:48
To do this, there's only two simple簡單 steps步驟 to follow遵循.
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你哋只需要簡單做兩樣嘢
01:51
First, you find and label標籤 a memory記憶 in the brain大腦,
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首先,你要搵同埋標記
大腦裏邊嘅一個記憶
01:54
and then you activate激活 it with a switch.
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然後用開關激活個記憶
01:58
As simple簡單 as that.
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就係咁簡單
01:59
(Laughter笑聲)
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(笑聲)
02:01
SR: Are you convinced相信?
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史︰你哋信未?
02:03
So, turns輪流 out finding發現 a memory記憶 in the brain大腦 isn't all that easy容易.
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實際上喺大腦裏面搵一個記憶
並唔係咁容易
劉︰冇錯
02:07
XLXl: Indeed講真. This is way more difficult困難 than, let's say,
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呢樣比喺禾稈裏面搵一支針仲難
02:09
finding發現 a needle in a haystack乾草堆,
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02:12
because at least最小, you know, the needle is still something
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因為至少支針你哋仲可以實在咁掂到
02:14
you can physically身體 put your fingers手指 on.
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02:17
But memory記憶 is not.
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但記憶唔係
02:19
And also, there's way more cells細胞 in your brain大腦
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而且,大腦裏面嘅細胞數量
多過禾稈裡面嘅雜草數目
02:22
than the number數量 of straws稭稈 in a typical典型 haystack乾草堆.
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02:27
So yeah, this task任務 does seem好似 to be daunting艱巨.
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的確,個項目睇起嚟幾令人心灰意冷
02:30
But luckily好彩呀, we got help from the brain大腦 itself本身.
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但係幸運嘅係
我哋由大腦自身獲得幫助
02:34
It turned打開 out that all we need to do is basically基本上
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所以我哋要做嘅就只係
畀大腦形成一個記憶
02:36
to let the brain大腦 form形式 a memory記憶,
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02:38
and then the brain大腦 will tell us which cells細胞 are involved涉及
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然後大腦會話畀我哋聽
邊啲細胞參與形成記憶
02:42
in that particular特定 memory記憶.
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02:44
SR: So what was going on in my brain大腦
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史︰咁當我諗返前度嘅時候
02:46
while I was recalling回顧 the memory記憶 of an ex?
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大腦會有咩變化?
02:48
If you were to just completely完全 ignore忽略 human人類 ethics倫理 for a second第二
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如果你唔講人道主義,將我嘅大腦切片
02:51
and slice up my brain大腦 right now,
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02:52
you would see that there was an amazing驚人 number數量
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你會發現當我諗返前度時
02:54
of brain大腦 regions一區 that were active積極 while recalling回顧 that memory記憶.
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有非常多嘅大腦區域會被刺激
02:57
Now one brain大腦 region一區 that would be robustly強勁 active積極
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而其中一個強烈活躍嘅區域係海馬體
03:00
in particular特定 is called the hippocampus海馬,
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03:02
which for decades幾十年 has been implicated牽連 in processing處理
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一個幾十年嚟被認為
會處理近期同親切記憶嘅區域
03:05
the kinds of memories記憶 that we hold舉行 near附近 and dear親愛的,
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03:07
which also makes使 it an ideal理想 target目標 to go into
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所以佢都係一個理想地方
畀人可以進入、尋找同啟動記憶
03:10
and to try and find and maybe reactivate激活 a memory記憶.
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03:13
XLXl: When you zoom縮放 in into the hippocampus海馬,
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劉︰當你令用顯微鏡觀察海馬體
03:15
of course課程 you will see lots of cells細胞,
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唔單止會見到好多細胞
03:17
but we are able to find which cells細胞 are involved涉及
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我哋仲能夠搵到
嗰啲參與某個記憶嘅細胞
03:20
in a particular特定 memory記憶,
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03:22
because whenever每當 a cell細胞 is active積極,
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因為當細胞活動時
03:24
like when it's forming形成 a memory記憶,
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例如當細胞建立某種記憶時
03:26
it will also leave離開 a footprint足跡 that will later之後 allow允許 us to know
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細胞會留低痕跡
我哋就可以透過痕跡
知道最近邊啲細胞啟動過
03:30
these cells細胞 are recently最近 active積極.
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03:32
SR: So the same相同 way that building建築 lights at night
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史︰呢樣就好似夜晚寫字樓著咗燈
03:34
let you know that somebody's probably可能 working工作 there at any given moment時刻,
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你會知道有人做緊嘢
03:37
in a very real真正 sense, there are biological生物 sensors傳感器
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同樣細胞都有咁嘅燈
不過叫生物感應器
03:41
within a cell細胞 that are turned打開 on
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當細胞做緊嘢嘅時候,生物感應器會著
03:43
only when that cell細胞 was just working工作.
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03:45
They're sort排序 of biological生物 windows that light up
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生物感應器就好似盞燈一樣
畀我哋知道細胞活動
03:47
to let us know that that cell細胞 was just active積極.
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03:49
XLXl: So we clipped part部分 of this sensor傳感器,
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劉︰所以我哋將生物感應器
連接到開關,控制呢啲細胞
03:51
and attached附加 that to a switch to control控制 the cells細胞,
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03:55
and we packed包裝 this switch into an engineered工程 virus病毒
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我哋將呢個開關擺喺
一個改造過嘅病毒裏面
03:59
and injected注入 that into the brain大腦 of the mice小鼠.
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將病毒注入老鼠大腦
04:01
So whenever每當 a memory記憶 is being formed形成,
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於是當一個記憶形成嗰陣
04:04
any active積極 cells細胞 for that memory記憶
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任何參與在內嘅細胞
都會裝上呢個開關
04:06
will also have this switch installed安裝.
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04:09
SR: So here is what the hippocampus海馬 looks睇黎 like
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史︰例如,呢個就係海馬體
建立咗一個恐懼記憶之後嘅樣
04:10
after forming形成 a fear恐懼 memory記憶, for example例子.
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04:13
The sea of blue藍色 that you see here
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呢張相藍色部分就係密集嘅腦細胞
04:15
are densely濃密 packed包裝 brain大腦 cells細胞,
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04:17
but the green綠色 brain大腦 cells細胞,
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而呢啲綠色嘅腦細胞
就係參與形成恐懼記憶
04:19
the green綠色 brain大腦 cells細胞 are the ones that are holding舉行 on
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04:21
to a specific特定 fear恐懼 memory記憶.
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04:23
So you are looking at the crystallization結晶
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你哋宜家睇到嘅
係恐懼快速形成嘅過程
04:25
of the fleeting短暫的 formation形成 of fear恐懼.
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04:27
You're actually講真 looking at the cross-section橫斷面 of a memory記憶 right now.
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正確啲嚟講係記憶嘅橫切面
04:31
XLXl: Now, for the switch we have been talking講嘢 about,
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劉︰我哋一直討論緊嘅開關需要快
04:33
ideally理想, the switch has to act行為 really fast快速.
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04:36
It shouldn't唔该 take minutes分鐘 or hours小時 to work.
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佢唔可以花幾分鐘或者幾個鐘去做到
04:39
It should act行為 at the speed速度 of the brain大腦, in milliseconds毫秒.
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佢應該以大腦嘅速度去做
即係以幾微秒為限
04:43
SR: So what do you think, Xu?
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史︰劉,咁你點睇?
04:44
Could we use, let's say, pharmacological葯理 drugs藥物
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我哋可唔可以用,例如藥物
啟動或者熄咗大腦細胞?
04:47
to activate激活 or inactivate滅活 brain大腦 cells細胞?
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04:49
XLXl: Nah唔係. Drugs藥物 are pretty messy混亂. They spread傳播 everywhere周圍.
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劉︰唔得。因為藥物會擴散,好麻煩
04:53
And also it takes them forever永遠 to act行為 on cells細胞.
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而且藥物作用係永遠嘅
04:56
So it will not allow允許 us to control控制 a memory記憶 in real真正 time.
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所以我哋唔能夠用藥物即時控制記憶
05:00
So Steve史蒂夫, how about let's zap the brain大腦 with electricity電力?
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咁史蒂夫,用電控制大腦你覺得點?
05:04
SR: So electricity電力 is pretty fast快速,
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史︰電非常之快
05:06
but we probably可能 wouldn't唔會 be able to target目標 it
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但係我哋未必可以將電帶到
負責某個記憶嘅細胞當中
05:08
to just the specific特定 cells細胞 that hold舉行 onto a memory記憶,
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05:10
and we'd我哋會 probably可能 fry the brain大腦.
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我哋甚至乎會灼傷大腦
05:12
XLXl: Oh. That's true真係. So it looks睇黎 like, hmm,
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劉︰哦。 的確係
所以我哋應該搵更好嘅方法
以光速進入大腦細胞
05:15
indeed講真 we need to find a better way
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05:18
to impact影響 the brain大腦 at the speed速度 of light.
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05:21
SR: So it just so happens發生 that light travels旅行 at the speed速度 of light.
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史︰正因為光本身就有光速
05:26
So maybe we could activate激活 or inactive無效 memories記憶
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或者我哋可以用光
嚟到激活同熄咗記憶
05:30
by just using使用 light --
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05:31
XLXl: That's pretty fast快速.
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劉︰光速非常快
05:33
SR: -- and because normally通常 brain大腦 cells細胞
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而且由於正常嘅大腦細胞對光冇反應
05:35
don't respond響應 to pulses脈衝 of light,
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05:36
so those that would respond響應 to pulses脈衝 of light
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因此嗰啲對光有反應嘅細胞
05:38
are those that contain包含 a light-sensitive光敏 switch.
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就係含有光敏感開關嘅細胞
05:41
Now to do that, first we need to trick把戲 brain大腦 cells細胞
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為咗令呢啲細胞對激光有反應
05:43
to respond響應 to laser激光 beams.
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我哋首先要呃腦細胞
05:44
XLXl: Yep. You heard聽到 it right.
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劉:你哋冇聽錯
05:45
We are trying試圖 to shoot開槍 lasers激光器 into the brain大腦.
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我哋嘗試將激光射入大腦
05:47
(Laughter笑聲)
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(笑聲)
05:49
SR: And the technique技術 that lets us do that is optogenetics光遺傳學.
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我哋靠嘅技術就係光遺傳學
05:52
Optogenetics光遺傳學 gave us this light switch that we can use
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光遺傳學畀咗光敏感開關我哋
令我哋能夠啟動或者熄咗腦細胞
05:56
to turn brain大腦 cells細胞 on or off,
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05:57
and the name名字 of that switch is channelrhodopsinchannelrhodopsin,
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而呢個光敏感開關個名
叫做光敏感通道
06:00
seen看到 here as these green綠色 dotsD attached附加 to this brain大腦 cell細胞.
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就係嗰啲黏著腦細胞嘅綠色小點
06:02
You can think of channelrhodopsinchannelrhodopsin as a sort排序 of light-sensitive光敏 switch
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你哋可以將光敏感通道
當做一種對光敏感
06:05
that can be artificially人工 installed安裝 in brain大腦 cells細胞
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可以俾人安裝入腦細胞嘅開關
06:08
so that now we can use that switch
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所以,宜家我哋可以簡單襟個開關
06:10
to activate激活 or inactivate滅活 the brain大腦 cell細胞 simply淨係 by clicking點擊 it,
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啟動或熄咗腦細胞
06:13
and in this case情況下 we click點擊 it on with pulses脈衝 of light.
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喺呢個情況,我哋用光脈衝開開關
06:15
XLXl: So we attach附加 this light-sensitive光敏 switch of channelrhodopsinchannelrhodopsin
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劉︰我哋將呢種
光敏感通道嘅光敏感開關
06:19
to the sensor傳感器 we've我哋都 been talking講嘢 about
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擺喺生物感應器上,並注入大腦
06:21
and inject注入 this into the brain大腦.
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06:24
So whenever每當 a memory記憶 is being formed形成,
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當一個記憶形成嘅時候
06:27
any active積極 cell細胞 for that particular特定 memory記憶
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有份形成嗰個記憶嘅細胞
都會有呢個光敏感開關
06:29
will also have this light-sensitive光敏 switch installed安裝 in it
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06:33
so that we can control控制 these cells細胞
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咁樣我哋就可以
通過照射激光控制呢啲細胞
06:35
by the flipping翻轉 of a laser激光 just like this one you see.
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06:39
SR: So let's put all of this to the test測試 now.
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史︰宜家就係測試所有嘢嘅時間
06:42
What we can do is we can take our mice小鼠
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我哋能夠做嘅就係
將老鼠放入一個咁嘅盒
06:44
and then we can put them in a box that looks睇黎 exactly完全 like this box here,
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06:47
and then we can give them a very mild溫和 foot隻腳 shock休克
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然後輕微點擊老鼠足部
令老鼠對呢個盒產生一個恐懼記憶
06:50
so that they form形式 a fear恐懼 memory記憶 of this box.
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06:52
They learn學習 that something bad happened發生 here.
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令佢哋知道盒入面有唔好嘅嘢發生
06:54
Now with our system系統, the cells細胞 that are active積極
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喺老鼠嘅海馬體裏面
06:56
in the hippocampus海馬 in the making決策 of this memory記憶,
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形成呢一個記憶嘅活躍細胞
都會有光敏感通道
06:59
only those cells細胞 will now contain包含 channelrhodopsinchannelrhodopsin.
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07:02
XLXl: When you are as small as a mouse鼠標,
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劉︰當你有一隻老鼠咁細
07:05
it feels感覺 as if the whole整個 world世界 is trying試圖 to get you.
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你會覺得成個世界都喺度想捉你
07:08
So your best最好 response響應 of defense防禦
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所以,你最好嘅防衛
係收埋自己、唔被發現
07:10
is trying試圖 to be undetected發現.
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07:13
Whenever每當 a mouse鼠標 is in fear恐懼,
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當老鼠處於恐懼狀態
07:15
it will show顯示 this very typical典型 behavior行為
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就會表現出呢一種典型行為
07:16
by staying at one corner角落 of the box,
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即係呆喺盒嘅角落唔郁
07:18
trying試圖 to not move移動 any part部分 of its body身體,
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07:21
and this posture姿勢 is called freezing凍結.
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呢一種狀態我哋稱之為「靜止」
07:24
So if a mouse鼠標 remembers記得 that something bad happened發生 in this box,
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如果老鼠記得個盒有唔好嘅事發生
07:29
and when we put them back into the same相同 box,
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而我哋將佢哋放返同一個盒時
佢哋本能反應就係靜止唔郁
07:31
it will basically基本上 show顯示 freezing凍結
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07:33
because it doesn't want to be detected檢測
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咁係因為佢哋唔想俾盒裡面
任何潛在嘅威脅物發現
07:35
by any potential threats威脅 in this box.
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07:38
SR: So you can think of freezing凍結 as,
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史︰因此,你哋可以將「靜止」
07:40
you're walking down the street minding介意 your own自己 business業務,
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諗成你喺街行,腦裡面諗著自己嘅嘢
07:42
and then out of nowhere無處 you almost爭 D run運行 into
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然後幾乎要撞到你嘅前女友或者前男友
07:43
an ex-girlfriend前女友 or ex-boyfriend前男友,
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07:46
and now those terrifying可怕 two seconds
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喺呢兩秒裏面
07:48
where you start初時 thinking思維, "What do I do? Do I say hi你好?
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你會諗︰我做咩好?打招呼?
同佢握手? 抑或轉身走?
07:50
Do I shake動搖 their佢哋 hand? Do I turn around and run運行 away?
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07:51
Do I sit here and pretend假裝 like I don't exist存在?"
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我係咪應該坐喺度扮唔存在?
07:53
Those kinds of fleeting短暫的 thoughts思想 that physically身體 incapacitate緻殘 you,
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呢啲突然喺腦海出現嘅諗法
令你無法控制自己嘅身體
07:56
that temporarily暫時 give you that deer-in-headlights鹿係車燈 look.
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令你暫時流露出孤獨無助嘅表情
07:59
XLXl: However然而, if you put the mouse鼠標 in a completely完全 different不同
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劉︰但係,如果你將老鼠
放喺一個完全唔一樣嘅新籠裡面
08:02
new新增功能 box, like the next one,
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好似跟著落嚟呢個咁
08:05
it will not be afraid害怕 of this box
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老鼠就唔會驚呢個籠
08:08
because there's no reason原因 that it will be afraid害怕 of this new新增功能 environment環境.
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因為老鼠冇理由去驚呢個新環境
08:12
But what if we put the mouse鼠標 in this new新增功能 box
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但如果我哋將老鼠放喺新籠裡面
同時用我哋用激光啟動恐懼記憶嘅話
08:15
but at the same相同 time, we activate激活 the fear恐懼 memory記憶
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08:19
using使用 lasers激光器 just like we did before?
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會發生啲咩?
08:22
Are we going to bring back the fear恐懼 memory記憶
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我哋係咪可以喺一個
完全唔一樣嘅環境裏面
喚醒返老鼠對第一個籠嘅恐懼記憶?
08:25
for the first box into this completely完全 new新增功能 environment環境?
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08:29
SR: All right, and here's呢度有 the million-dollar百萬美元 experiment實驗.
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史︰呢個係價值百萬美元嘅實驗
08:31
Now to bring back to life the memory記憶 of that day,
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宜家我哋講返當日嘅記憶
08:34
I remember記得 that the Red Sox袜队 had just won贏得,
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我記得嗰日波士頓紅襪隊贏咗比賽
08:36
it was a green綠色 spring春天 day,
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嗰日又係一個生機勃勃嘅春天日子
08:38
perfect完美 for going up and down the river
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極適合喺河邊散步
同埋去 North End 買一啲甜酥卷
08:40
and then maybe going to the North End結束
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08:43
to get some cannolis蛋卷, #justsayingjustsaying.
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08:45
Now Xu and I, on the other hand,
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另一方面,我同劉
08:48
were in a completely完全 windowless black room間房
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喺一個冇窗、全黑嘅房裡面
08:51
not making決策 any ocular movement運動 that even remotely遠程 resembles好似 an eye眼睛 blink眨眼
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眼球郁都唔動
因為隻眼郁嘅話離遠睇似係眨眼
08:54
because our eyes眼睛 were fixed固定 onto a computer計數機 screen屏幕.
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所以我哋眼都冇眨咁望著電腦螢幕
08:57
We were looking at this mouse鼠標 here trying試圖 to activate激活 a memory記憶
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我哋喺度望緊隻老鼠
嘗試第一次用我哋嘅技術
去啟動一個記憶
08:59
for the first time using使用 our technique技術.
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09:01
XLXl: And this is what we saw.
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劉︰呢個就係我哋睇到嘅
09:04
When we first put the mouse鼠標 into this box,
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當我哋第一次將老鼠放入呢個籠
09:06
it's exploring探索, sniffing around, walking around,
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老鼠會探索,聞嘢,周圍走,做自己嘢
09:09
minding介意 its own自己 business業務,
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09:11
because actually講真 by nature自然,
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因為老鼠天生係好好奇嘅動物
09:13
mice小鼠 are pretty curious好奇 animals動物.
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09:15
They want to know, what's going on in this new新增功能 box?
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佢哋想知道,呢個新嘅籠有乜嘢
09:17
It's interesting有趣.
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老鼠好得意
09:19
But the moment時刻 we turned打開 on the laser激光, like you see now,
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但當我哋啟動激光嘅一刻
就好似你宜家睇到咁
09:22
all of a sudden突然 the mouse鼠標 entered進入 this freezing凍結 mode模式.
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老鼠即刻進入靜止狀態
09:25
It stayed here and tried試過 not to move移動 any part部分 of its body身體.
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老鼠呆咗,唔郁
09:30
Clearly清楚 it's freezing凍結.
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好明顯,老鼠定咗型
09:31
So indeed講真, it looks睇黎 like we are able to bring back
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睇起上嚟,我哋做到
09:34
the fear恐懼 memory記憶 for the first box
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將第一個籠嘅恐懼記憶帶到去新環境
09:36
in this completely完全 new新增功能 environment環境.
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09:39
While watching this, Steve史蒂夫 and I
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當我哋睇到結果,史蒂夫同我都震驚咗
09:41
are as shocked震驚 as the mouse鼠標 itself本身.
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就好似隻老鼠一樣
09:44
(Laughter笑聲)
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(笑聲)
09:45
So after the experiment實驗, the two of us just left the room間房
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實驗完咗之後,我哋離開間房
09:48
without saying anything.
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冇講過嘢
09:50
After a kind一種 of long, awkward尷尬 period時期 of time,
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經過好長又尷尬嘅一段時間
史蒂夫終於打破沉默
09:53
Steve史蒂夫 broke打破 the silence沉默.
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09:55
SR: "Did that just work?"
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史︰我當時話「我哋嘅技術係得嘅? 」
09:58
XLXl: "Yes," I said. "Indeed講真 it worked工作!"
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劉:我話「係,真係得咗! 」
10:01
We're really excited興奮 about this.
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我哋對結果都非常激動
10:03
And then we published發表 our findings發現
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然後我哋將個發現刊登喺自然期刊度
10:05
in the journal雜誌 Nature自然.
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10:07
Ever since因為 the publication出版 of our work,
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自從發表咗我哋嘅研究之後
10:10
we've我哋都 been receiving接收 numerous眾多 comments評論
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我哋喺網上收到好多留言
10:12
from all over the Internet互聯網.
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10:14
Maybe we can take a look at some of those.
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我哋可以睇其中一啲
10:18
["OMGGGGGOMGGGGG FINALLY最後... so much more to come, virtual虛擬 reality現實, neural神經 manipulation操縱, visual視覺 dream夢想 emulation仿真... neural神經 coding編碼, 'writing的寫作 and re-writing重新編寫 of memories'記憶 ', mental心理 illnesses疾病. Ahhh the future未來 is awesome"]
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[ 天啊。最後…有咁多嘢!虛幻科技、神經控制、視覺夢想嘅再現、
神經編碼、「寫同重寫記憶 」、精神疾病。將來係咁好嘅。]
10:20
SR: So the first thing that you'll你咪會 notice通知 is that people
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史︰首先你會注意到啲人
對呢項研究有好強烈嘅意見
10:22
have really strong opinions意見 about this kind一種 of work.
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10:25
Now I happen發生 to completely完全 agree同意 with the optimism樂觀
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宜家,我開始非常認同
第一個人嘅樂觀睇法
10:28
of this first quote報價,
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10:29
because on a scale規模 of zero to Morgan摩根 Freeman's弗里曼的 voice聲音,
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因為相對於Morgan Freeman 嘅評論
10:31
it happens發生 to be one of the most evocative喚起 accolades榮譽
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呢個係我有生以嚟聽到最好嘅讚美說話
10:34
that I've heard聽到 come our way.
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10:35
(Laughter笑聲)
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(笑聲)
10:37
But as you'll你咪會 see, it's not the only opinion意見 that's out there.
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但係就好似你哋睇到嘅一樣
呢個並唔係唯一嘅意見
10:39
["This scares害怕 the hell地獄 out of me... What if they could do that easily容易 in humans人類 in a couple夫婦 of years?! OH MY GOD WE'RE DOOMED注定"]
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[ 太不可思議啦…如果佢哋可以喺幾年內
將呢種技術應用到人身上會點? 天啊!我哋命中註定係咁。]
10:41
XLXl: Indeed講真, if we take a look at the second第二 one,
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劉︰如果我哋睇睇第二個留言
10:43
I think we can all agree同意 that it's, meh,
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我諗我哋全部人都覺得
嗰個人講嘅嘢冇咁正面
10:45
probably可能 not as positive積極.
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10:47
But this also reminds us that,
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但呢樣都提醒我哋
10:49
although雖然 we are still working工作 with mice小鼠,
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雖然我哋宜家仍然以老鼠做實驗對象
10:52
it's probably可能 a good idea想法 to start初時 thinking思維 and discussing討論
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但我哋確實應該開始思考同討論
10:55
about the possible可能 ethical倫理 ramifications後果
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記憶控制帶嚟嘅道德爭議
10:58
of memory記憶 control控制.
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11:00
SR: Now, in the spirit精神 of the third第三 quote報價,
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史︰透過第三個留言
11:02
we want to tell you about a recent最近 project項目 that we've我哋都 been
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我想話畀你哋聽一個
我哋最近喺實驗室開展嘅項目
11:04
working工作 on in lab實驗室 that we've我哋都 called Project項目 Inception初始.
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叫「盜夢空間」
11:07
["They should make a movie電影 about this. Where they plant植物 ideas想法 into peoples人民 minds頭腦, so they can control控制 them for their佢哋 own自己 personal gain獲得. We'll我哋就 call it: Inception初始."]
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[「佢哋應該整一部關於呢樣嘢嘅電影。當佢哋將記憶植入人嘅意識裏面,
佢哋就能夠控制人,從而達到個人利益。佢哋就能夠控制人,從而達到個人利益。
11:10
So we reasoned理由 that now that we can reactivate激活 a memory記憶,
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所以我哋開始諗
雖然我哋可以重啟一個記憶
11:14
what if we do so but then begin初時 to tinker修補 with that memory記憶?
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但如果我哋唔小心
改造咗個記憶,咁點呢?
11:17
Could we possibly可能 even turn it into a false memory記憶?
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我哋會唔會將個記憶
變成一個錯誤嘅記憶?
11:20
XLXl: So all memory記憶 is sophisticated複雜 and dynamic動態,
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劉︰所有記憶都係複雜而且有動態變化
11:24
but if just for simplicity簡單, let's imagine想象 memory記憶
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但我哋可以簡單將記憶當成係一齣電影
11:27
as a movie電影 clip剪輯.
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11:28
So far what we've我哋都 told you is basically基本上 we can control控制
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正如我哋一路所講嘅
我哋可以控制電影嘅播放掣
11:31
this "play" button of the clip剪輯
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11:33
so that we can play this video視頻 clip剪輯 any time, anywhere地方.
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所以我哋可以隨時隨地播呢部電影
11:37
But is there a possibility可能性 that we can actually講真 get
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但有冇可能我哋可以
進入大腦編輯呢部電影
11:40
inside the brain大腦 and edit編輯 this movie電影 clip剪輯
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11:43
so that we can make it different不同 from the original源語言?
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令佢同原本有唔同?
11:46
Yes we can.
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係,我哋可以做到
11:48
Turned打開 out that all we need to do is basically基本上
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我哋需要做嘅只係
用我哋之前用過嘅激光
11:50
reactivate激活 a memory記憶 using使用 lasers激光器 just like we did before,
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重新啟動一個記憶
11:54
but at the same相同 time, if we present目前 new新增功能 information信息
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但係如果我哋同時將新嘅資訊
擺落去舊嘅記憶當中
11:58
and allow允許 this new新增功能 information信息 to incorporate into this old memory記憶,
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12:02
this will change the memory記憶.
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舊嘅記憶會改變
12:04
It's sort排序 of like making決策 a remix混音 tape磁帶.
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就好似整混合錄音咁
12:08
SR: So how do we do this?
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史︰咁我哋點樣做呢?
12:11
Rather than finding發現 a fear恐懼 memory記憶 in the brain大腦,
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與其喺大腦搵到恐懼記憶
12:13
we can start初時 by taking採取 our animals動物,
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我哋可以喺動物裏面搵
12:14
and let's say we put them in a blue藍色 box like this blue藍色 box here
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即係我哋將動物放入
一個咁樣嘅藍色籠裡面
12:17
and we find the brain大腦 cells細胞 that represent代表 that blue藍色 box
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我哋喺動物個腦裏面
搵返代表藍色籠嘅腦細胞
12:20
and we trick把戲 them to respond響應 to pulses脈衝 of light
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然後我哋令呢啲腦細胞對光有反應
12:22
exactly完全 like we had said before.
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同我哋之前做嘅一模一樣
12:24
Now the next day, we can take our animals動物 and place地方 them
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第二日,我哋可以將動物放入
一個佢哋從來冇遇過嘅紅色籠
12:26
in a red box that they've佢地已經 never experienced經歷 before.
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12:29
We can shoot開槍 light into the brain大腦 to reactivate激活
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我哋可以向佢哋大腦照射激光
重啟佢哋對藍色籠嘅記憶
12:31
the memory記憶 of the blue藍色 box.
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12:33
So what would happen發生 here if, while the animal動物
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咁當動物諗返藍色籠嘅嘢時
12:35
is recalling回顧 the memory記憶 of the blue藍色 box,
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我哋對佢哋輕微電擊幾次,會點呢?
12:36
we gave it a couple夫婦 of mild溫和 foot隻腳 shocks衝擊?
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12:39
So here we're trying試圖 to artificially人工 make an association協會
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我哋就嘗試人為咁
令藍色籠嘅記憶同電擊關連起嚟
12:42
between之間 the memory記憶 of the blue藍色 box
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12:44
and the foot隻腳 shocks衝擊 themselves自己.
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我哋想將兩樣嘢連埋一齊
12:45
We're just trying試圖 to connect連接 the two.
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12:47
So to test測試 if we had done so,
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為咗證實我哋成功
12:49
we can take our animals動物 once一旦 again
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我哋再將老鼠放入藍色籠
12:50
and place地方 them back in the blue藍色 box.
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12:52
Again, we had just reactivated激活 the memory記憶 of the blue藍色 box
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我哋今次只係重啟老鼠對藍色籠嘅記憶
12:55
while the animal動物 got a couple夫婦 of mild溫和 foot隻腳 shocks衝擊,
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但老鼠卻感覺到足部有微弱電擊
12:57
and now the animal動物 suddenly突然 freezes凍結.
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然後佢哋突然靜止唔郁
12:59
It's as though雖然 it's recalling回顧 being mildly輕度 shocked震驚 in this environment環境
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所以就算實際上冇電擊都好
老鼠始終記返起被電擊
13:02
even though雖然 that never actually講真 happened發生.
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因此,老鼠形成咗一個錯誤嘅記憶
13:05
So it formed形成 a false memory記憶,
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13:07
because it's falsely虛假 fearing an environment環境
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因為技術上嚟講
佢哋驚錯咗一個冇電擊嘅環境
13:09
where, technically技術 speaking,
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13:10
nothing bad actually講真 happened發生 to it.
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13:13
XLXl: So, so far we are only talking講嘢 about
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劉︰目前為止,我哋只係討論咗
呢種用光控制嘅開掣
13:15
this light-controlled光控 "on" switch.
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13:18
In fact事實, we also have a light-controlled光控 "off" switch,
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其實我哋都有光控制嘅閂掣
13:21
and it's very easy容易 to imagine想象 that
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而且我哋可以好容易想像到
13:23
by installing安裝 this light-controlled光控 "off" switch,
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通過安裝呢種光控制嘅閂掣
13:25
we can also turn off a memory記憶, any time, anywhere地方.
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我哋可以隨時隨地閂咗一個記憶
13:31
So everything we've我哋都 been talking講嘢 about today今日
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我哋今日所講嘅嘢
13:33
is based基於 on this philosophically哲學 charged指控 principle原則 of neuroscience神經
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都係基於神經科學一條哲學性嘅原理
13:38
that the mind介意, with its seemingly看似 mysterious神秘 properties性能,
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就係,思想睇起嚟好神秘
13:42
is actually講真 made作出 of physical物理 stuff啲嘢 that we can tinker修補 with.
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但佢實際上係由物質組成
兼可以俾我哋利用嘅嘢
13:46
SR: And for me personally,
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史︰我見到一個世界
13:47
I see a world世界 where we can reactivate激活
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我哋可以重新啟動任何我哋鍾意嘅記憶
13:49
any kind一種 of memory記憶 that we'd我哋會 like.
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13:51
I also see a world世界 where we can erase擦除 unwanted多餘 memories記憶.
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我仲見到一個世界
我哋可以抹走我哋唔想要嘅記憶
13:54
Now, I even see a world世界 where editing編輯 memories記憶
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宜家,我甚至見到
記憶編輯已經成為現實中嘅一部分
13:56
is something of a reality現實,
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13:58
because we're living生活 in a time where it's possible可能
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因為我哋生活嘅時代
13:59
to pluck questions個問題 from the tree of science科學 fiction小說
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已經有可能將科幻小說裡邊嘅問題
14:02
and to ground地面 them in experimental實驗 reality現實.
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通過實驗將佢哋帶到嚟現實世界
14:04
XLXl: Nowadays現時, people in the lab實驗室
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劉︰宜家,我哋實驗室嘅人員
同全世界嘅人員
14:06
and people in other groups all over the world世界
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14:08
are using使用 similar類似 methods方法 to activate激活 or edit編輯 memories記憶,
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都用緊類似嘅方法啟動或者編輯記憶
14:12
whether係唔係 that's old or new新增功能, positive積極 or negative,
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無論嗰啲記憶係舊、新、正面、負面
14:16
all sorts各種 of memories記憶 so that we can understand理解
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——總之所有類型嘅記憶
等我哋能夠了解記憶係點樣運作嘅
14:19
how memory記憶 works工程.
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14:20
SR: For example例子, one group in our lab實驗室
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史︰例如,我哋實驗室嘅一個團隊
14:22
was able to find the brain大腦 cells細胞 that make up a fear恐懼 memory記憶
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發現咗形成恐懼記憶嘅腦細胞
14:25
and converted轉換 them into a pleasurable愉快 memory記憶, just like that.
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並將嗰啲腦細胞轉化成快樂記憶
就好似嗰個咁
14:28
That's exactly完全 what I mean about editing編輯 these kinds of processes過程.
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嗰個就係我想講嘅編輯過程
14:31
Now one dude夥計 in lab實驗室 was even able to reactivate激活
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宜家,實驗室人員
甚至可以喺雄性老鼠當中
14:33
memories記憶 of female女性 mice小鼠 in male男性 mice小鼠,
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啟動佢哋對雌性老鼠嘅記憶
14:35
which rumor謠言 has it is a pleasurable愉快 experience經驗.
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有流傳話人員有好愉快嘅經歷
14:38
XLXl: Indeed講真, we are living生活 in a very exciting令人興奮 moment時刻
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劉︰我哋正生活喺一個好開心嘅時刻
14:42
where science科學 doesn't have any arbitrary任意 speed速度 limits限制
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因為呢一刻科學除咗受制於
我哋嘅想像力之外,就再冇限制
14:46
but is only bound绑定 by our own自己 imagination想象.
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14:49
SR: And finally最後, what do we make of all this?
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史︰最後,我哋做到啲咩呢?
14:51
How do we push this technology技術 forward向前?
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我哋點樣繼續發展呢一個技術?
14:53
These are the questions個問題 that should not remain保持
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呢啲問題唔應該剩係留返畀
實驗室嘅人解答
14:55
just inside the lab實驗室,
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14:57
and so one goal目標 of today's今日嘅 talk was to bring everybody大家
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我哋今日演講嘅目的就係令所有人
知道現代神經科學有可能嘅事
14:59
up to speed速度 with the kind一種 of stuff啲嘢 that's possible可能
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15:02
in modern現代 neuroscience神經,
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15:03
but now, just as importantly重要,
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但宜家重要嘅係
令所有人都參與個討論
15:05
to actively積極 engage從事 everybody大家 in this conversation談話.
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15:08
So let's think together一起 as a team團隊 about what this all means意味着
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等我哋好似一個團隊咁一齊諗下
神經科學可以做到啲咩
15:10
and where we can and should go from here,
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我哋可以點樣繼續往前走
15:13
because Xu and I think we all have
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因為劉同我都認為
我哋所有人面前都有一啲重大決定要做
15:15
some really big decisions決定 ahead提前 of us.
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史、劉︰多謝
15:17
Thank you.
XLXl: Thank you.
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15:18
(Applause掌聲)
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(鼓掌)
Translated by Jason chan
Reviewed by Michael Ge 葛叔

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ABOUT THE SPEAKERS
Steve Ramirez - Neuroscientist
When Steve Ramirez published his latest study in Science, it caused a media frenzy. Why? Because the paper was on implanting false memories in the brains of mice.

Why you should listen

Steve is a graduate student at MIT’s Brain and Cognitive Sciences department pursuing a Ph.D. in neuroscience. His work focuses on finding where single memories are located throughout the brain, genetically tricking the brain cells that house these memories to respond to brief pulses of light, and then using these same flickers of light to reactivate, erase and implant memories. The goals of his research are twofold: to figure out how the brain gives rise to the seemingly ephemeral process of memory, and to predict what happens when specific brain pieces breakdown to impair cognition. His work has been published in Science and covered by New Scientist, Discover, Scientific American, and Gizmodo.

Ramirez aims to be a professor who runs a lab that plucks questions from the tree of science fiction to ground them in experimental reality. He believes that a team-oriented approach to science makes research and teaching far more exciting. When he’s not tinkering with memories in the lab, Ramirez also enjoys running and cheering on every sports team in the city of Boston.

More profile about the speaker
Steve Ramirez | Speaker | TED.com
Xu Liu - Neuroscientist
In his groundbreaking work, Xu Liu investigated how to activate and deactivate specific memories in mice.

Why you should listen

During his PhD, Xu Liu studied the mechanisms of learning and memory, using fruit flies as a model system. By changing the expression of certain genes in the fly brain, he generated smart flies that can learn many times faster than their peers. Using live imaging, he also detected learning-induced changes in the brain cells and observed memory formation inside the brain with light.

After graduation, he moved to MIT and joined Dr. Susumu Tonegawa's lab as a postdoctoral associate. He continued his pursuit of memory with light there. Instead of just watching memory formation, he developed a system in mice where one can not only identify and label cells in the brain for a particular memory, but also turn these cells on and off with light to activate this memory at will. This work was published in Science and has been covered by the media worldwide. Liu passed away in February 2015.

More profile about the speaker
Xu Liu | Speaker | TED.com