"The machine in your skull that everyone has".

The brain is a machine that is constructed for change, "it confers on us the ability to do things tomorrow that we can't do today."

With an infant, he argues, they are born stupid. They don't respond to much, they have no perceptual ability, and there is not really very much indication that there is a person on board. They can only in a very primitive way, control their own body movements, and it will take months for them to learn, to change and adapt to doing so properly.

By the time the brain has learnt to control speaking, it has mastered understanding tens if not hundreds of thousands of separate objects in the world around itself. Each is stored and indexed inside the vastly accelerating powers of the brain of a three year old.

By this age the brain has developed a multitude of cognitive skills and is rewriting itself to be more efficient. Very much a thinking machine.

Individual skills and abilities are then shaped into childhood by the environment the brain finds it in, and the culture around it. The brain learns to adapt and develop complex skills to fit in with the crowd. Because of this, no two of us have the same set of skills and abilities - everyone develops a different mental repertoire to fit in with a cross section of different groups and different situations.

Although the brain starts out near identical to other brains, with the same basic wiring and structure, it is this plasticity, this ability to continually self-rewrite and pile complexity upon complexity, wiping out old pathways to make way for new, that really makes every being unique.

An adult brain has a huge repertoire of acquired skills and abilities; movement patterns hardcoded into the brain that define a person, and can be recalled as complex instruction sets that allow movements and behaviors to be played back from recorded memory, without consciously thinking about it.

In the lab, creatures such as mice, monkeys, and students are taught new skills, their brains under close scrutiny as the changes that occur throughout this learning process are tracked and studied in depth, as the mainstay of decoding this plasticity of the brain.

Two great epochs in brain plasticity have been discovered, and are slowly being unraveled:

The critical period: Initial set-up of brain functions and structure during womb/infant stages.

Adult Plasticity: The brain's ability to re-arrange and indeed erase older functions, and structures, in order to mater a wide repertoire of skills and abilities.

It is very hard for the brain to rewire in the adult phase, that which was set up in infant, as the infant epoch typically deals with initial standards such as the development of language specific structures. Wiring in sound and sight, smell taste, and balance, to dedicated processors within it, written and built themselves during the infant phase In short, perception of the world around it.

Instead, the adult plasticity changes the response to learned behaviors, changing the learned behaviors themselves and refining practised techniques.

The most important events that have occurred in your brain, is you. Derived from the Adult Plasticity period, billions of events have added up, with billions of structural changes that have added up to your self perception.