who's in charge - you or your brain?

Guardian | It is clear at this point that we are irrevocably tied to the 3lb of strange computational material found within our skulls. The brain is utterly alien to us, and yet our personalities, hopes, fears and aspirations all depend on the integrity of this biological tissue. How do we know this? Because when the brain changes, we change. Our personality, decision-making, risk-aversion, the capacity to see colours or name animals – all these can change, in very specific ways, when the brain is altered by tumours, strokes, drugs, disease or trauma. As much as we like to think about the body and mind living separate existences, the mental is not separable from the physical.

This clarifies some aspects of our existence while deepening the mystery and the awe of others.

For example, take the vast, unconscious, automated processes that run under the hood of conscious awareness. We have discovered that the large majority of the brain's activity takes place at this low level: the conscious part – the "me" that flickers to life when you wake up in the morning – is only a tiny bit of the operations. This understanding has given us a better understanding of the complex multiplicity that makes a person. A person is not a single entity of a single mind: a human is built of several parts, all of which compete to steer the ship of state. As a consequence, people are nuanced, complicated, contradictory. We act in ways that are sometimes difficult to detect by simple introspection. To know ourselves increasingly requires careful studies of the neural substrate of which we are composed.