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There's a sound that makes kids cover their ears. The grown-up standing right there hears nothing at all. He isn't pretending. Somewhere along the way to adulthood, he really lost it. We were all kids once. As we grew up, some feelings quietly slipped away. Not because our memory failed, but because our bodies and brains changed.
Number one: hearing very high sounds. Deep in your ear is a row of tiny hairs. The ones for the highest sounds wear out first, and they never grow back. Someone even built a little speaker that plays a piercing tone. It's used to shoo teenagers away from shop doors. Plenty of people over twenty-five can't hear it at all. Number two: the world feels huge. The table is taller than your head, and you stand on tiptoe to reach the doorknob.
Scientists once ran an experiment. They made adults feel they had turned into a doll eighty centimeters tall. Right away, everything around them looked bigger and farther off. No wonder: a small body means a big world. As we grew taller, that huge world shrank along with us. Number three: sweetness. The sweetness adults like best is about a can of soda. Kids like it at least twice as sweet.
Only around fifteen or sixteen, when we stop growing, do our tastes settle down to adult levels. Number four: wanting to look at everything. Adults see like a flashlight, lighting up one small spot. Kids see like a lantern, lighting up everything around. An ant, a leaf, a puddle. To a kid, each one is a big deal.
Number five: summers that went on forever. Researchers asked four hundred ninety-nine people. Those over forty, looking back, felt time moved slowly in childhood. The older they got, the faster it went. One explanation: the brain mostly records what's new. As a kid, every day had a first time. A summer packed with memories looks very long in hindsight. So next time a kid shrieks over a piece of candy or an ant, don't call it an overreaction. For them, these things really are bigger, sweeter, newer.
And you can win a little of it back. Go somewhere you've never been, try something you've never done. Your days will stretch out again. Which childhood feeling do you still remember? Tell me in the comments.
Many feelings aren’t forgotten. Our bodies and brains grew up.
The world under the table really was this big.
Put simply: you didn’t forget it. It left you.

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