挖掘我们的大脑：为什么有些人更聪明？

图片来源：百度图片

AT EINSTEIN's autopsy in1955, his brain was something of a disappointment: it turned out to be a tadsmaller than the average Joe's. Indeed, later studies have suggested a minimallink between brain size and intelligence. It seems brain quality rather thanquantity is key.

在1955年对爱因斯坦的尸检中，他的大脑似乎有点令人失望：原来它比一般人的大脑还要小。确实，后来的研究也表明，大脑大小与智力之间的联系极小。似乎大脑品质比数量更为关键。

One important factorseems to be how well our neurons can talk to each other. Martijn van denHeuvel, a neuroscientist at Utrecht University MedicalCenter in theNetherlands, found that smarterbrains seem to have more efficient networks between neurons - in other words,it takes fewer steps to relay a message between different regions of the brain.That could explain about a third ofthe variation in a population's IQ, he says.

其中一个重要的因素似乎在于，我们的神经元互相之间传递信息的能力有多强。荷兰乌德勒支大学医学中心神经系统科学家Martijnvan den Heuvel发现，更聪明的大脑好像神经元之间有效的网状组织更多——也就是说，在大脑不同区域之间传播一个信息需要的步骤更少。他说，这也许可以对人类智商存在大约三分之一的差异作出解释。

Another key factor isthe insulating fatty sheath encasing neuron fibres, which affects the speed ofelectrical signals. Paul Thompson at the Universityof California, Los Angeles, has found a correlation betweenIQ and the quality of the sheaths (The Journal of Neuroscience, vol 29,p 2212).

另一个关键的因素即围绕神经纤维的隔离脂肪鞘，它能影响电信号的速度。洛杉矶加利福尼亚大学的PaulThompson已发现智商与脂肪鞘品质之间的对应关系（见《神经科学杂志》第29册，2212页）。

We still don't knowexactly how much genes contribute to intelligence, with various studies comingup with estimates ranging from 40 to 80 per cent. This wide range of estimatesmight have arisen because genes contribute more to IQ as we get older,according to a study published last year. By comparing the intelligence of11,000 pairs of twins, Robert Plomin of King's College London found that at age9, genes explain 40 per cent of the variation, but by 17 they account forroughly two-thirds (Molecular Psychiatry, DOI:10.1038/mp.2009.55).

尽管有多方面的研究提出，基因对智力所起作用占有40%到80%不等的估计值比值，我们仍然不知道确切的数字是多少。根据去年公布的一项研究，这一宽泛围的估计值比值可能会有所上升，因为随着我们年龄的增长，基因会对智力的作用会越来越大。通过对11000对双胞胎智力的比较，伦敦国王学院的RobertPlomin发现，9岁的时候，40%的智力差异源于基因，但到了17岁，比例大约上升到了2/3（见DOI:10.1038/mp.2009.55网站精神病学）。

How could that be?Perhaps the genes affect how our brain rewires itself as we mature.Alternatively, they may dictate whether someone is likely to seek outstimulating experiences to help their brain grow and develop. "If we arepredisposed to have a talent, we may actively seek out an environment to suitit," says Thompson.

那将会怎样？或许，随着我们渐渐长大，基因会影响我们的大脑如何进行自身重新连接。或者，它们可能会决定一个人是否愿意寻找刺激性的体验来帮助他们的大脑成长和发育。Thompson说，“如果我们想要拥有才干，那我们可能就要积极地去寻找一个环境来配合它的发展。”

注：原文来自外文网站，译文系笔者原创翻译。