Summary Episode two, "What Makes Me?", explores the question of how the brain gives rise to our thoughts, emotions, our memories and personality. Philosophers and great thinkers have for millennia pondered the question of how physical stuff can give rise to mental processes. Last century, the new field of neuroscience joined the discussion, and Dr. David Eagleman explains that to a neuroscientist, the answers to such questions lie in a deep understanding of the brain. The process of becoming who you are begins at birth. The human brain starts life remarkably unfinished, which accounts for the fact that babies are completely dependent on adults, compared to many mammals that can walk, fly and swim soon after they are born. A baby has almost as many neurons or nerve cells as an adult brain but instead of being connected to each other, the great majority are unconnected. Wiring up begins immediately, and rapidly, as the child's brain starts to adapt to whatever environment - culture, habitat, language - it's born into. Animals may be able to start life almost ready to go but they have none of the flexibility and adaptability of the human brain. The process of becoming a fully developed human takes a long time, and the brain doesn't stop forging new connections when we become adults. As we make new memories, learn new skills, and have life experiences the brain is constantly and dynamically rewiring itself. It never stops. Nor do we - the human brain is always changing, and therefore so are we. From cradle to grave, we are works in progress.

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