translation.en: SR: -- and because normally brain cells don't respond to pulses of light, so those that would respond to pulses of light are those that contain a light-sensitive switch.
translation.zh: 史蒂夫： 而且由于脑细胞通常 对光波没有反应， 所以能对光波产生反应的 就是那些挟带光敏开光的细胞。