時差N小時:我的大腦是靜止的還是不斷變化的?

Scientists used to think that for all its complexity,the brain was pretty static.

科學家們過去常常認為，大腦因為其復雜性而呈現出靜止狀態(tài)。

Once the brainmatured, it essentially stoppedgrowing and changing.

一旦成熟，大腦基本上就會停止生長和變化。

And when neurons, or brain cells, were lostordamaged, they were gone for good.

當神經元或大腦細胞丟失或損壞時，大腦就會壞死掉。

But recent discoveries have caused neuroscientists tochange their tune.

但是最近的發(fā)現讓神經學家改變了看法。

The human brain isanything but static-in fact, it's constantly growing and changing as itadapts to new informationand circumstances.

人類的大腦絕不是靜止的，事實上，它是隨著對新信息和新環(huán)境的適應不斷生長和變化的。

For example, scientists now know that there's a mechanism in the hippocampus a brainpartinvolved with memory, among other things that gives birth to new brain cells.

舉個例子來說，現在科學家們知道大腦內存在一種叫做海馬體的記憶機制，可以產成新的大腦細胞。

Scientists don'tknow exactly why the brain makes new cells or what the cells do.

但是，科學家們不能確切地知道大腦為什么能生成新細胞，而這些細胞又能做什么。

They may have something todo with forming memories, or be used to replace dead ordamaged cells.

它們可能和形成記憶有關，或者被用于代替老去或損壞的細胞。

In any case, in a recent experiment, scientists working with mice shut down their brains' abilitytomake new cells.

不管怎樣，在最近的一次實驗中，科學家們用老鼠進行實驗，他們消除了這些老鼠們大腦生成新細胞的能力。

At first, the researchers observed that the mice had reduced functioning in cellularmechanismsin the brain important for memory formation.

起初，研究人員觀測到，老鼠大腦中對記憶生成非常重要的細胞機制的功能降低了。

But after about six weeks, they noticed that the mice's brains had begun to compensatebymaking existing neurons more active.

但是大約六周之后他們又發(fā)現，老鼠的大腦通過使現有的神經元變得更加活躍從而彌補之前的損失。

Relatively newborn neurons created before the researchersshut down the neuron birthingprocess reacted by living longer than they normally would-almostas though they knew thatreplacements would not be forthcoming and so they had to workovertime to help the brain getback on course.

相對地，在研究人員阻止神經元生成之前生成的神經元比一般生成的存活更長—就好像它們知道自己不會被很快代替，所以它們必須延時工作來幫助大腦回到正軌上。

This research is of the most basic, foundational kind. But knowing more about how thebrainresponds to changes could eventually have profound implications for how doctorsunderstandand treat Alzheimer's, dementia, and other brain illnesses.

這項研究是最為基礎的研究。但是，對大腦是如何變化的了解越多，就會對醫(yī)生了解與治療老年癡呆癥、癡呆和其它大腦疾病產生更為深遠的意義。