A strike to your patellar tendon triggers an electrical impulse that travels up a sensory neuron to your spine.

敲击你的髌骨肌腱会触发电子脉冲。该脉冲将沿着感觉神经元上传到你的脊椎。

When we tap your, let's say your patellar tendon that causes a stretch in a muscle spindle, this sends a signal back to the sensory neuron, which activates a motor neuron in the spinal cord to cause your knee to kick up.

当我们敲击你的，比方说你的髌骨腱，它会导致肌肉纺锤体的拉伸，这会向感觉神经元发送信号，这会激活脊髓中的运动神经元，使你的膝盖抬起。

If you hit my patellar tendon with a reflex hammer, my leg is going to jerk forward, and it's going to jerk forward a lot faster and a lot more predictably than if I had to think about it myself.

如果你用反射锤击打我的髌腱，我的腿就会向前猛拉，而且它会比我自己考虑时更快、更可预测地向前猛拉。