The power of tiny things has been very much on my mind. With good cause. One Saturday morning last month, I rolled over and the room started spinning. The ceiling light whirled round and round. Gravity seemed unreliable. I shut my eyes and held onto the side of the mattress to keep from falling off the planet. The slightest movement caused the world around me to resume its spiraling frenzy. I recalled the old David Bowie song featuring an astronaut who drifted off into space, and I feared a similar fate.
With my husband's help, I managed to get dressed. He drove me to the emergency department at Centra Southside Hospital. The attending doctor made an immediate diagnosis. He said I had a classic, text-book case of something called benign positional vertigo. He explained that it was caused by the displacement of small rocks in the inner ear. In medical terms, these rocks are called otoliths. They are composed of limestone and protein. When the otoliths are positioned where they belong, they enable a person to maintain balance. Misplaced, they send incorrect signals to the brain about the body's orientation in space. The brain tries to reconcile false information from the affected ear with accurate information from the unaffected ear. This creates a sensation of uncontrolled spinning.
Rocks in my head! My children have probably suspected this all along, but it came as a surprise to me.
I wondered about the size of these rocks. According to Timothy C. Hain, MD, a doctor specializing in dizziness, their size in humans ranges from 3 to 30 microns with an average size of 10 microns. Apparently fish have them too, and they're a lot bigger in fish—big enough to measure on a ruler in fractions of an inch.
For the human size, however, I couldn't envision how big a micron was. I knew the definition, that a micron was one-millionth of a meter, but that was too abstract a concept. I had a ruler that included centimeters (hundredths of meters) and millimeters (thousandths of meters), but that still didn't help me envision the size of something that might be as tiny as 3 millionths of a meter.
Turning to the internet for help, I found the site of a company called Industrial Specialities Manufacturing. They explained that a micron was about 1/25,000 of an inch. That meant a line of 2,500 otoliths with an average size of 10 microns would measure one inch. I started to get a vague feeling for how small these things were.
I looked farther and found other micron comparisons from Clearstream Filters, Inc. According to them, the limit of visibility is about 40 microns. In other words, even a large human otolith at 30 microns is too small to be seen with the unaided eye. For comparison, a human hair is about 70 microns in diameter. An average otolith of 10 microns compares with a single grain of talcum powder. At the small end, an otolith of 3 microns is between one-quarter and one-third the size of a red blood cell.
So as rocks go, otoliths are indeed teeny. But for being such small things, they certainly have a dramatic effect on a person's perception of the entire world. That fact led me to think about how other seemingly small things can have huge effects. How a teacher's kind word can inspire a career or how a gentle touch of the hand can turn despair into hope. A Biblical parable identifies a mustard seed as the smallest of garden seeds, and it says that faith of even this tiny size can change the world.
When I think about the size of the entire earth, I wonder if a person by comparison might be about the size of an otolith. And then I remember that one small child born more than 2,000 years ago certainly put his spin on all of history. As I prepare to celebrate the remembrance of his birth, I wish you and your family a Merry Christmas and a happy holiday season.
Originally published December 2011 in the author's newspaper column, "Happy to Be Here," appearing in the Farmville Herald. Now available in Happy to Be Here: A Transplant Takes Root in Farmville, Virginia, by Karen Bellenir, © 2016 Pier Press; reprinted with permission.
