I live in a house of stone. I never leave, but some claim I've been lost. Through seven windows I see the world. I need to exercise or I become lazy. When I die, my house slowly decays too. What am I?

The fascinating riddle points to the brain, a remarkable organ housed safely within the "stone house" of the skull. The "seven windows" through which it perceives the world refer to our primary sensory organs: the two eyes, two nostrils, two ears, and the mouth, all serving as conduits for information to reach the brain. Though it never physically leaves its protective casing, some might claim it's "lost" when cognitive function declines or consciousness fades.

This incredible organ, weighing around three pounds in adults, is the command center for everything we think, feel, and do. It's largely composed of fat and contains billions of neurons, forming trillions of connections that allow information to travel at speeds up to 250 miles per hour. The brain is constantly active, even during sleep, and consumes about 20% of the body's energy.

Just like any other part of the body, the brain needs exercise to stay sharp. Regular physical activity can improve memory and thinking skills, and reduce the risk of cognitive decline. Engaging in mentally stimulating activities like puzzles, learning new skills, or playing music also helps maintain cognitive fitness. When the body dies, the brain, being biochemical, ceases to function as the necessary chemicals are no longer produced, leading to the decay of its cells and the loss of memories. However, research suggests brain cells can show resilience for some time after clinical death.