When you read these words, hundreds of millions of nerve cells are electrically and chemically active in your brain. This activity enables you to recognize words, sense the world, learn, enjoy and create new things, and be curious about the world around you. Indeed, our brains of Homo Sapiens are the most fascinating physical substances ever emerged on earth, some 200,000 years ago. The brain is so curious and ambitious that it strives to understand itself and cure its fragile elements when it becomes sick