Wiping Out Bad Memories

A hot topic in neuroscience is memory. Not only increasing it, but erasing it...of the sort that Jim Carrey fools with in the movie, Eternal Sunshine of the Spotless Mind.

Last week researchers from the University of Toronto published a paper in Science that shows successful obliteration of a fearful memory in mice. This study is significant in that they focused on a specific set of nerve cells that were associated with a very specific memory.

Researchers trained mice to fear a tone, by matching that tone with an electric shock to their feet. So when the tone rang, the mice froze in fear.

Then they flipped a genetically engineered-switch that wiped out a set of neurons, called the CREB-making neurons. CREB is a protein that spikes in the lateral amygdala, when we experience a scary event.

Now, when the tone rang, the mice kept on with their mouse-like activities. No other memories, nor their ability to form new memories, were affected. The effect was specific, potent and long-lasting.

We need to note we are not anywhere close to erasing memory in humans. And really, we need to think hard about which memories to squash, if we ever could. After all, memory is how we learn.

Like that time last winter when I thought it was a fun idea to test walking on thin ice. Think I want to remember that one.

消除糟糕的記憶

記憶是神經(jīng)科學(xué)的一個(gè)很熱門的話題，就像電影《美麗心靈的永恒陽光》（Eternal Sunshine of the Spotless Mind）里的Jim Carrey一樣，人們嘗試消除記憶，而不僅僅是增強(qiáng)我們的記憶力。

上周來自多倫多大學(xué)（University of Toronto）的研究人員們在《科學(xué)》（Science）雜志上發(fā)表的一篇文章顯示，他們成功地把老鼠的一種可怕的記憶消除掉了。該項(xiàng)研究的重大意義在于為研究人員們集中研究了與某種特定記憶相關(guān)的特定的一組神經(jīng)細(xì)胞。
 
研究人員們通過對老鼠加以訓(xùn)練，使它們對某一聲音感到恐懼。使用的方法是，研究人員在老鼠聽到這種聲音的時(shí)候，就對老鼠的腳施加電擊。所以，一旦這種聲音響起來，這些老鼠就會(huì)嚇得不能動(dòng)彈。

然后，研究人員們通過基因改變技術(shù)消除了一組名為“生成CREB”的神經(jīng)細(xì)胞。CREB是一種蛋白質(zhì)，當(dāng)我們經(jīng)歷令人害怕的事情的時(shí)候，外側(cè)杏仁核中CREB的含量會(huì)升高。

現(xiàn)在，當(dāng)這種聲音響起的時(shí)候，這些老鼠仍然繼續(xù)自己的活動(dòng)。這些老鼠的其它記憶以及它們形成新記憶的能力都沒有受到影響。這種改變的效果具有特定性、長期性而且強(qiáng)大。

我們需要注意的是，我們還遠(yuǎn)遠(yuǎn)不能消除人的記憶。實(shí)際上，如果我們能消除記憶，我們需要認(rèn)真想想哪些記憶需要消除。畢竟我們是通過記憶來學(xué)習(xí)的。

比如，去年冬天的時(shí)候我認(rèn)為在薄冰上行走以檢測冰的厚度是個(gè)有趣的想法�，F(xiàn)在我覺得我還是想珍藏這個(gè)記憶。

Vocabulary:

Neuroscience: 神經(jīng)科學(xué)
Obliteration: 記憶的根除
Neuron: 神經(jīng)細(xì)胞
Spike: 升高
Lateral: 邊緣的
Amygdala: 杏仁核
Potent: 強(qiáng)大的
Scary: 害怕的
Squash: 壓碎；擠壓

知識(shí)點(diǎn)滴：

spike作為名詞是“長釘”的意思。但是它作為動(dòng)詞的時(shí)候的一個(gè)常用意思是“迅速升高、提高”。比如利息的陡然升高， “Interest rates spiked up last week”（上周利息陡然升高）。