Many people wondered why they had a clear mind instead of sleepiness when they faced "urgent situation" at night even though they did not drink any coffee. For example, the writer who is pressed for the deadline at night and the situation which we have to overcome slumber when a baby cries.

▲ When you drink coffee, caffeine prevents combining adenosine and its receptor, so you feel not tired

Until now, it is not clear that which part of our brain controls body vigilance. Recently, a research team started to understand how the human brain controls awakening when we need it. The research team paid attention to the dorsal raphe nucleus. People who were affected this part felt excessive sleepiness. So, they pointed this part of the brain and indagated. First of all, they researched the dopamine neurons' role of dorsal raphe nucleus. To experiment with rats, they made "urgent situation" such as meeting opposite sex, giving them foods and natural enemies. Then, they recorded the DRNDA activity. When rats are sleeping, the activity of neurons is the lowest, but they are facing an "urgent situation". It becomes much higher.

▲ Location of the dorsal raphe nucleus

In sequence, the researchers wanted to know that DRNDA activity is a simple signal or active system of the brain. So, they used onto-genetic. It is the science technology that suppresses or revitalizes certain neurons by using light. When the rats had taken a sleep, they revitalized DRNDA neurons, then they woke up abruptly. Also, they had fostered "urgent situation" to rats and suppressed the DRNDA neurons, upon that surprising things happened. They did not react to the "urgent situation" anymore. If we prove that his experiment applies the same to a human, it will be a great discovery for insomnia and sleep disorder patients.

▲ How DRNDA system works

There are a lot of opinions about the brain. Even Albert Einstein used only 10 percent of his brain and everything we know about the brain is much less than we do not know. By knowing the brain, we can approach to ourselves and understood each other well because the brain is the part which determines every creatures' thought.

2019. 1. 6 by Kim Dae-hwan