Here are some tricks of living in a human body that you may not know about, because they happen automatically.
The eye trick. How come the lights don’t go out when you blink? Think about that. The world should go dark, but we perceive a continuous view, even though blinking all the while. Scientists at the University of California Berkeley looked into this. In “Why the lights don’t dim when we blink,” they describe how their research “shows that the brain works extra hard to stabilize our vision despite our fluttering eyes.” Details are published in Current Biology, where you can learn about “automatic calibration of gaze direction” during blinking.
Voice tricks. The human voice is phenomenally versatile. Think of all the sounds it can emit just in talking. Add singing, and the voice’s range and flexibility is truly amazing. On The Conversation, Noel Hanna offers some interesting facts. First, he shows that in Chinese, with its five tonal rules in language, a speaker can emit 840 distinct sounds, but only half of those are actually used in speaking; the range of possible words is actually 2,000 x 2,000, or “4 million possible unique words using this system of pronunciation.” Then those words are strung together in complex sentences. “And that is just one language,” he says. “Each language has its own set of different sounds, which may or may not overlap with other languages.” After some anatomy lessons and three interesting videos, including an MRI of an opera singer (worth watching), Hanna has answered many questions about the mechanics of the voice, but not how humans came into possession of such remarkable equipment.
Hair power. Hair is so strong and break resistant, researchers at the University of California San Diego want to imitate it to make body armor. Here are some factoids about the material you brush or comb each day.
Hair has a strength to weight ratio comparable to steel. It can be stretched up to one and a half times its original length before breaking. “We wanted to understand the mechanism behind this extraordinary property,” said Yang (Daniel) Yu, a nanoengineering Ph.D. student at UC San Diego and the first author of the study.
“Nature creates a variety of interesting materials and architectures in very ingenious ways. We’re interested in understanding the correlation between the structure and the properties of biological materials to develop synthetic materials and designs — based on nature — that have better performance than existing ones,” said Marc Meyers, a professor of mechanical engineering at the UC San Diego Jacobs School of Engineering and the lead author of the study.
Such a common material, yet such fascinating properties.
Hair, eyes, the voice – we could go on and on, but that’s enough boggle for today. Sing while you comb your hair and blink.