Playing sounds into the right ears stimulating the left hemispher of 27 volunteers was more likely to wake them up than if the noises were played into their left ears.
2017年6月六级真题(第三套)阅读 Section A
Some previous studies have suggested that challenging your brain with mentally stimulating activities might help.
2016年6月六级真题(第二套)听力 Section C
柯林斯高阶英汉双解学习词典释义
VERB
刺激;激励;促使;促起
To stimulate something means to encourage it to begin or develop further.