60秒科学:Smaller Fingers Mean More Sensitive Fingertips

Smaller Fingers Mean More Sensitive Fingertips
A study in the Journal of Neuroscience finds that people with smaller fingers have more sensitive fingertips, probably due to a higher concentration of touch receptors in a given area. Cynthia Graber reports.

Smaller can sometimes be better, at least when it comes to fingers. It turns out that people with smaller fingers have more sensitive fingertips, according to a study in the Journal of Neuroscience.

Researchers at Canada’s McMaster University enlisted¹ 100 volunteers, and measured each study subject’s index fingertip. The researchers pressed parallel grooves² against the subjects’ fingertips. If they could feel those grooves, then the next set got narrower and narrower. Scientists compare it to an eye test, where you attempt to recognize progressively smaller letters until they’re no longer distinguishable.

Well, people with the smallest fingertips felt the narrowest grooves. The scientists postulated³ that this might be because they have a higher density⁴ of receptors crowded together and sending signals to the brain. It would be like a larger pixel count that makes up a clearer digital image.

To test the idea, the researchers measured the density of sweat pores. Because they knew that touch receptor cells cluster around sweat pores. And people with smaller and more sensitive fingers did have a higher concentration of sweat pores. Which means more receptors. And for their discovery, the researchers get a big hand.
 

1 enlisted   

adj.应募入伍的v.（使）入伍， （使）参军( enlist的过去式和过去分词 )；获得（帮助或支持）

参考例句：

• enlisted men and women 男兵和女兵
• He enlisted with the air force to fight against the enemy. 他应募加入空军对敌作战。 来自《现代汉英综合大词典》

2 grooves   

n.沟( groove的名词复数 )；槽；老一套；（某种）音乐节奏v.沟( groove的第三人称单数 )；槽；老一套；（某种）音乐节奏

参考例句：

• Wheels leave grooves in a dirt road. 车轮在泥路上留下了凹痕。 来自《简明英汉词典》
• Sliding doors move in grooves. 滑动门在槽沟中移动。 来自《现代汉英综合大词典》

3 postulated   

v.假定，假设( postulate的过去式和过去分词 )

参考例句：

• They postulated a 500-year lifespan for a plastic container. 他们假定塑料容器的寿命为500年。
• Freud postulated that we all have a death instinct as well as a life instinct. 弗洛伊德曾假定我们所有人都有生存本能和死亡本能。 来自辞典例句

4 density   

n.密集，密度，浓度

参考例句：

• The population density of that country is 685 per square mile.那个国家的人口密度为每平方英里685人。
• The region has a very high population density.该地区的人口密度很高。