The Dhaka Times Desk People just yawn. But less and more is the only difference. But we know that people yawn when they fall asleep. Is it really so? This report is written with all the strange ideas of yawning.
We know that people yawn when they sleep. And then his sleep was arranged. Or it is said, ..so-and-so is sleepy, arrange a bed. But in recent times, there are many juicy stories about this Haitola. Today, this report has been mainly prepared on the subject of this hightola.
One of our daily tasks is to yawn! But we don't know why we yawn. Moreover, yawning is beneficial to the body? That is also unknown to us. But even if we don't try to know, the researchers are still behind it. This yawn may not have been studied in detail before. But still people are curious.
The oldest theory about yawning is probably that of Hippocrates. There he said:
# Yawning brings 'good' air into the body and expels 'bad' air.
# Yawning brings more oxygen into the body to give us energy and carbon dioxide is released.
However, studies have not proven these theories, but contrary data have been reported. It states,
# People who need more oxygen don't actually yawn more than others. And so yawning is still a mystery.
Most recent theory:
Most of the researchers agree that:
# Yawning keeps our brain cool.
# When the brain gets hot for some reason, we want to yawn.
# Our brain consumes a lot of energy.
Although the brain is small in size compared to the rest of the body, it consumes about 40 percent of metabolic energy. So the brain often gets hot, just like our computer gets hot when it runs for long periods of time. The brain heats up when we are tired, bored or sick. And yawning causes the brain to cool down a bit. Then our mind becomes a little more alert than before.
Brain temperature depends on three factors:
1. Arterial blood flow levels
2. blood temperature
3. Heat generated in the brain.
Yawning works well in the first two cases. Arterial circulation increases and relatively cool blood enters the brain.
One theory in evolutionary research suggests that when the human brain was developing, arteries began to form around the skull to keep the brain cool. It is at this time that physical activity such as yawning occurs.
But no matter how many words, we can understand one thing well and that is that yawning will not cause any physical harm to us.
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