How Caffeine Works?

Why does caffeine wake you up? Whu do many people consume so much caffeine? Now that I'm drinking so much energy drinks, coffee and tea. I want to find out how caffeine works.

1) Adenosine (A den o sine)
Adenosine is created in the brain to promote sleep. It binds to adenosine receptors(A specialized group or cell of nerve ending respond to stimulation). The binding of adenosine causes oneself to fall asleep or slow down nerve cell activity.

2) Caffeine
When you consume caffeine, it therefore binds to the adenosine receptor. What caffeine does is surrounding adenosine receptors so the cell cannot see adenosine anymore. When you increase more caffeine, cells eventually cannot preceive adenosine. Therefore, instead of slowing down cell's activity(as adenosine would) it speeds up your brain cells.

Caffeine also causes the brain's blood vessels to constrict. Because of that, it blocks adenosine's ability to open up so you won't fall asleep. However, this effect might cause adenosine to disagree with the blood vessels compression and might cause a headache.

3) Adrenaline
Now that you're awaked, you have increased neuron firing in the brain. Your brain's activity speeds up and thinks some sort of emergency must be occurring. It then releases hormones to produce adrenaline. Adrenaline gives you energy to meet your physical and emotional stress.