external stimulus

基本解释

Use external stimuli.
使用外在刺激。
In brain-imaging studies, brains of introverts show more activity in response to external stimuli.
对大脑成像的研究发现，内向者的大脑对于“外部刺激”表现出较为活跃的反应。
It can be useful to filter out external stimuli if you are writing an email in a noisy coffee shop, for example, or are searching for a camouflaged insect in a rainforest.
例如，要是你在在嘈杂的咖啡馆里写一封电子邮件或在雨林里搜寻一只伪装的昆虫，能过滤掉外部的刺激就很有用。

Using these bio-transistors, researchers gain access to data not previously available (like whether an individual cell has been exposed to certain external stimuli), in addition to allowing them to control basic functions like cellular reproduction.
ENGADGET
An external stimulus such as music can actually block some of the internal stimuli trying to reach the brain—such as fatigue-related messages from muscles and organs.
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