The human brain is inarguably the most complicated 'thing' the world has ever seen. Everyone of the 7 billion people living on this planet today has one, and this 'machine of sorts' is in control of everything we have ever known. We would not have thought, personality, interactions, speech, memory, hearing, nothing at all. For everything that the brain controls, neurologists are still uncertain about many things this slimy organ can do. There is no correct answer is to what is unconsciousness, how our personally is determined, why we sleep and dream, how we store memory, why everyone has different perception, among many others. The reason there is so much uncertainty stems from the complications of the brain. An average brain has roughly 100 billion (10 to the 11th power) neurons, with each of these neurons having connections with around 10,000 of other neurons, forming synapses to create the sensations and thought that we have. When one of these 100,000,000,000,000 potential connections occur, something within our thought process will be changed. You should be cognizant that there are merely 400 million blades of grass in a 100 m football field. The amount of connections in the brain leave me stunned, for I cannot even picture the space they would take up if they were visible to the naked eye.
It is extremely important to keep the brain healthy because brain cells are only formed in fetal development, and after that there are no new ones made, so it is essential to take care of it by eating correctly, sleeping enough, and being conscience of your decisions.
I believe that as humans we are incapable of grasping the concept of such large exponential powers and relating them to daily life. Seeing all the brain holds is truly amazing, for i never new a 3 pounded organ could hold so many connections that make us individuals.