为什么人接吻的时候会闭上眼？

The real reason people close their eyes when they kiss is because the brain can't deal with more than two things at once.
人们接吻时闭上眼睛真正的原因是大脑不能同时处理两件以上事情。

When people pucker up the brain finds it difficult to process the sensation if cognitive power is also being used to analyse what we see, said psychologists from Royal Holloway, University of London.
人们嘟起嘴时，如果也一并用到认知力，则大脑很难处理感觉知觉，伦敦大学皇家霍洛威学院的心理学家如是说。

Tactile awareness depends on the level of perceptual load in a concurrent visual task. The cognitive psychologists reached their conclusion without studying people actually kissing. Instead people were asked do visual tests while their response to something touching their hands was measured.
触觉觉知取决于同一时间发生的认知量水平。认知心理学家得出此结论并没有真正去研究实际接吻的人。而是给人们一边做视觉测试，一边测量有实物接触他们手部时他们的反应。

The academics found that the visual field overrides tactile responses - meaning people would struggle to continue kissing if what they were looking at became more difficult to process.
专业人员发现视觉要凌驾于触觉觉知，也就是说，要是人们所看到的事物很难加工处理，则很难继续亲吻。

If people are focusing strongly on a visual task, this will reduce the awareness of stimuli in other senses.
人们注意力高度集中在视觉任务上，那么对由其它感官带来的刺激的敏感度就会降低。

The findings could also explain why people often shut their eyes whilst reading braille or when dancing.Shutting out the visual input leaves more mental resources to focus on other aspects of our experience.
研究发现同样解释了为何人们读布莱叶盲文或者跳舞的时候常常会闭起眼睛。闭上眼睛没有视觉信息输入时，人们就有更多大脑资源来集中关注其它方面的体验。