60秒科学:Brain Knows It's Duck Reason

When an Iraqi reporter threw his shoe at President Bush, University of Washington neurologists were delighted. But not because of politics. The fling was just real-world evidence of a theory they were testing. As the shoe flew, Bush ducked while Iraqi Prime Minister Maliki, who was standing¹ right beside him, barely flinched². The reason, the researchers say, is that we have a dual³ vision system. Our brains "see" things well before our eyes do. Their report is in the June 11th issue of the journal Current Biology.

The scientists contend that Bush ducked because his brain’s action pathway categorized the trajectory⁴ of the shoe as a threat well before his perception pathway began to track its flight. Meanwhile, Maliki realized the shoe wasn’t headed his way and didn’t take evasive action. The scientists say this mirrors computer simulations where test subjects respond much faster to approaching visual stimuli⁵ when those objects are on a trajectory lined up with their heads. Basically, your brain will tell you whether an item is a threat even before you know you saw it. The findings could apply to everyone from ballplayers to loafers.

—Adam Hinterthuer

 

1 standing   

n.持续，地位；adj.永久的，不动的，直立的，不流动的

参考例句：

• After the earthquake only a few houses were left standing.地震过后只有几幢房屋还立着。
• They're standing out against any change in the law.他们坚决反对对法律做任何修改。

2 flinched   

v.（因危险和痛苦）退缩，畏惧( flinch的过去式和过去分词 )

参考例句：

• He flinched at the sight of the blood. 他一见到血就往后退。
• This tough Corsican never flinched or failed. 这个刚毅的科西嘉人从来没有任何畏缩或沮丧。 来自辞典例句

3 dual   

adj.双的；二重的，二元的

参考例句：

• The people's Republic of China does not recognize dual nationality for any Chinese national.中华人民共和国不承认中国公民具有双重国籍。
• He has dual role as composer and conductor.他兼作曲家及指挥的双重身分。

4 trajectory   

n.弹道，轨道

参考例句：

• It is not difficult to sketch the subsequent trajectory.很容易描绘出它们最终的轨迹。
• The path followed by a projectile is called its trajectory.抛物体所循的路径称为它的轨道。

5 stimuli   

n.刺激（物）

参考例句：

• It is necessary to curtail or alter normally coexisting stimuli.必需消除或改变正常时并存的刺激。
• My sweat glands also respond to emotional stimuli.我的汗腺对情绪刺激也能产生反应。