Abstract
The human gestation process of about 40 weeks in the womb is said to trace the spectacular life history of 4 billion years. That history is also found in the brain. The brain has been hierarchically constructed from the primary neural tube which originated in protochordata about 500 million years ago, to the brain stem, archicortex and then neocortex, as a new part surrounding old parts left inside. And in the course of the evolution of human beings, the brain has taken up various environmental factors and adequate conditions for living in its neural networks. This report considers in such an evolutionary process how "consciousness" was born and how it developed with the brain structure, the neural networks and those functions.
