时差N小时:能读懂心思的机器

The electroencephalograph, or EEG, is a machinecommonly used by doctors and researchers who wantto know what the brain is doing without having toopen up someone's head and look inside.

脑电图仪，简称EEG，是一种医生或研究人员经常使用的机器，通过它可以得知人脑如何运转，而不用开启人的大脑直接进行观察。

In fact, even if you were to look inside the head,you still couldn't see the brain "doing" anything—theenergy brains use to operate is not visible.Nevertheless, brain activity can be recorded on an EEG just by taping a few electrodes tosomeone's scalp. How is that?

实际上，即使你直接观察大脑内部，仍然看不到大脑如何工作，因为大脑利用能量使身体运转的过程是不可见的。尽管如此，大脑的活动仍可以通过EEG来记录，操作时只要将一些电极连接到人的头皮就可以了。

The answer is that the brain runs on electrical energy. Individual brain cells, called neurons,regularly discharge tiny electrical impulses between themselves: this is the way theycommunicate. All these electrical impulses add up to create what are called "brain waves."

使它如此神奇的原因在于大脑依靠电运作。单个的大脑细胞叫做神经元，神经元定期相互释放微小的电子脉冲：这就是信息传递的方式。所有的这些电子脉冲叠加在一起形成了我们所说的脑电波。

An EEG relies on the fact that this electrical energy can be transmitted along a thin metalwire. By placing electrodes on someone's scalp, you can get the electricity from their brain totravel across the wire and into the EEG, where it is charted on a graph. Then, by looking at alarge number of graphs taken when test subjects are doing different things—such as reading,resting, listening to music, or sleeping—researchers can distinguish different characteristicbrain wave patterns. Once there is a standard of healthy patterns to refer to, it then becomespossible to recognize abnormal brain waves that signal something going awry.

EEG正是基于电能通过细金属线传输的原理制成。通过把电极连接到被测者的头皮，大脑中的电能就能通过电线到达EEG，然后被制成图表。然后，测试不同对象做不同的事情，比如看书、休息、听音乐、或者睡眠时的脑电波并绘制成图表。通过观察这些大量图表，研究人员就可以区分不同脑电波模式特点。只要设置一个正常模式作为参考，那么就有可能识别异常的脑电波信号。

It isn't really reading your mind, but the EEG is a machine that can read the overallelectrical state of your brain. Since its creation in 1929, the EEG has proved an invaluable toolin understanding sleep disorders, in diagnosing patients for epilepsy and brain tumors, and in awhole host of other medical areas.

EEG这种机器并不能真的读懂你的心思，但它能全面观察你的脑电波信号状况。自从在1929年被发明以来，EEG被公认为研究睡眠紊乱、诊断癫痫和脑瘤和其它医学领域的大多数疾病的得力助手。