What Makes Me?

Many newborn animals are born ready for the world, compared to human babies who are born helpless. The unfinished brains of young humans allows them to develop and adapt to whichever environments they are born into.

An experiment in a shop window demonstrates why teens feel far more self-conscious than adults in the same situation. The activity in the teenager’s medial prefrontal cortex plays an important role in how young adults perceive themselves.

The brains of London taxi drivers were tracked before, during and after their training, and results showed that a part of their brain had grown. The adult brain isn’t fixed. Its networks can reconfigure themselves according to our experiences and our environment.

A study of nuns’ brains produces an unexpected revelation. A third of the brains tested at autopsy showed signs of Alzheimer’s but cognitive tests had revealed that the brain owners had shown no symptoms of this terrible disease. What was going on?

A typical 2-year-old is building 2 million new connections every second, but after the age of two this growth is halted, and a process of pruning begins. The process of becoming someone is about pruning back the brain’s connections.

Henry Molaison couldn't form new memories. His case reveals something important about the brain’s ability to think into the future. Both the past, and the future are constructions of the same networks in the brain.

Explore how we are our brain, how our personality, emotions and memories are encoded as neural activity. The process of becoming continues through our lives. We change our brain and our brain changes us. Premieres Wednesday, October 21, 2015, 10-11 p.m. ET.