It is nothing remarkable to look at-a wrinkled object about the size of a number 13 chicken-but it consists of a complex and intricately tangled mass of nerve cells, called neurons.
It sits inside the skull, immersed in a fluid that cushions it from sudden impacts to the head.
Weighing in at around 1.3 kilograms, it is one of the largest organs in the human body.
The basic facts about the brain are well known.
