英语听力文摘 English Digest 426、健忘症（在线收听）

Amnesia
健忘症

When we remember something, the neurons in our brains communicate with each other in a particular way. The chemical and sometimes even structural changes that occur create a pathway called a memory trace.

Signals traveling along these traces are what allow us to remember things. When the chemical changes first occur, they create short term memory, or things we remember for only a brief time.

But short- term memory can become long term memory if the memory trace is activated enough so that it creates a long-term pathway in the brain. This process is called consolidation.

When something interrupts the memory-storage process–like a hard knock to the head–newly formed memories aren’t stored for the long run and you can’t remember things that just happened. This is called anterogradeamnesia.

Retrograde amnesia which is when you can’t recall things from your long term memory either. Luckily, in many cases of amnesia memory eventually returns, although the incident that caused amnesia is often never recalled.

我们在记忆一些事情的时候，大脑里的神经元会以一种特殊的方式进行交流。这种化学物质的结构时而发生变化产生一种叫“记忆痕迹”的路径。

信号通过这些路径传输，这样我们就可以记住事情了。化学物质最初发生变化时，就制造出短期记忆或是一些我们只能记很短时间的事情。

如果记忆痕迹足够活跃在大脑里制造出一条长期路径的话，短期记忆可以变成长期。这个过程叫加强。

当记忆储存的过程被打断——就像头被狠狠的敲击。新形成的记忆就不会持续很久，所以就不能记住刚刚发生的事情。这叫作顺行性遗忘症。

逆行性遗忘症是不记得以前发生的事。幸运的是，在许多健忘症的案例中，大多数最终都会恢复记忆。虽然引起失忆的原因也通常不记得。