The test records the electrical activity of the brain.

这个测试显示出大脑的电流活动。

This is a useful device for detecting electrical activity.

这是用来探测电流活动的仪器。

It can also sense electrical activity in the brain through the hair.

它也可以透过头发感知到脑电的活动。

During REM sleep, our brain's electrical activity mirrors its activity when we're awake.

在快速眼动睡眠期，我们大脑的脑电活动反映了我们醒着时大脑的活动。

Researchers also tested the electrical activity of single intestinal sensory nerve cells.

研究者同时还检测了单一小肠神经细胞的电行为。