The question about ice that has scientists perplexed is, why is it so slippery? One of the first theories was that our skates exert pressure, which lowers the melting point causing a thin layer of water on top of the ice. This theory was thrown out the window when it was discovered that we do not cause enough pressure for that to happen. The other two theories now floating around is that friction melts the ice, or the ice/air boundary continually has a thin layer of water. It’s possible that both are correct, as they each have experimental evidence.
Why we yawn and why yawning is contagious, is a question that has yet to be answered. There were a few reasons about why we yawn that were discredited. One was that it was due to a lack of oxygen, the other was that yawns are contagious to build empathy between yawners. Scientists agree that we yawn more when we are tired, but it seems to be a little more complicated than that. One theory being that it regulates the temperature of the brain and keeps us alert in times of stress. They have determined that there are different causes and a variety of functions for yawns and that contagious yawning is more common among family and friends, than with strangers. They also found that changes in brain chemistry trigger yawns, that we yawn more during the summer season and that infants, and people with autism or schizophrenia aren’t affected by others yawning.
Researchers have discovered that our memories are stored in a scattered group of neurons, but how our brain retrieves those memories, is not understood. To recall memory, the correct assortment of neutrons have to be activated by the brain. Researches are still unsure if the brain pulls memory from those neutrons, or uses them to re-form the memory.