时差N小时 什么是条件反射(下)

Once it reaches the spinal¹ cord, the impulse is routed speedily back to the muscle originally stimulated².

一旦到达脊髓，神经冲动便会迅速返回至最初受到到刺激的肌肉。

This process occurs almost instantaneously, before we’ve even had time to consciously register that the reflex has happened.

整个过程几乎是在瞬间发生的，甚至在我们意识到之前，条件反射就已经发生了。

Although a reflex is automatic, it can change over time, depending on the regularity³ of the stimulus⁴.

虽然条件反射是自发形成的，但它会随时间变化，这取决于刺激发生的频率。

If a stimulus is repeated continuously, the reflex first undergoes sensitization, meaning that it increases in response.

如果某种刺激在不断地重复，条件反射首先会对这种刺激变得敏感，预示着条件反射的反应次数会增加。

But if the stimulus is repeated beyond a certain point, the reflex begins to decrease until it disappears.

但如果这种重复性的刺激超过了某个点时，条件反射次数就会开始减少至消失。

In other words, you can tame a reflex by, for instance, hearing a sudden loud noise repeatedly until you stop jumping.

换句话说，条件反射是可以克服的，比如反复听突如其来的巨响，直到你不会被吓一跳为止。

1 spinal   

adj.针的，尖刺的，尖刺状突起的；adj.脊骨的，脊髓的

参考例句：

• After three days in Japan,the spinal column becomes extraordinarily flexible.在日本三天，就已经使脊椎骨变得富有弹性了。
• Your spinal column is made up of 24 movable vertebrae.你的脊柱由24个活动的脊椎骨构成。

2 stimulated   

a.刺激的

参考例句：

• The exhibition has stimulated interest in her work. 展览增进了人们对她作品的兴趣。
• The award has stimulated her into working still harder. 奖金促使她更加努力地工作。

3 regularity   

n.规律性，规则性；匀称，整齐

参考例句：

• The idea is to maintain the regularity of the heartbeat.问题就是要维持心跳的规律性。
• He exercised with a regularity that amazed us.他锻炼的规律程度令我们非常惊讶。

4 stimulus   

n.刺激，刺激物，促进因素，引起兴奋的事物

参考例句：

• Regard each failure as a stimulus to further efforts.把每次失利看成对进一步努力的激励。
• Light is a stimulus to growth in plants.光是促进植物生长的一个因素。