The Secret You

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Duration: 1 hour

With the help of a hammer-wielding scientist, Jennifer Aniston and a general anaesthetic, Professor Marcus du Sautoy goes in search of answers to one of science's greatest mysteries: how do we know who we are? While the thoughts that make us feel as though we know ourselves are easy to experience, they are notoriously difficult to explain. So, in order to find out where they come from, Marcus subjects himself to a series of probing experiments.

He learns at what age our self-awareness emerges and whether other species share this trait. Next, he has his mind scrambled by a cutting-edge experiment in anaesthesia. Having survived that ordeal, Marcus is given an out-of-body experience in a bid to locate his true self. And in Hollywood, he learns how celebrities are helping scientists understand the microscopic activities of our brain. Finally, he takes part in a mind-reading experiment that both helps explain and radically alters his understanding of who he is.


9 items
  • The Secret You

    Mathematician Marcus du Sautoy acts as a human guinea pig to find out something that can be impossible to explain, what makes us, us?

  • Becoming Aware of Ourselves

    Children and animals take part in the Mirror Recognotion test to see when they become aware of themselves.

  • Anatomy of the Brain

    Taking a closer look at the human brain and what parts deal with consciousness and awareness.

  • Measuring Consciousness

    Marcus undergoes testing to see how his brain responds to a 'consciousometer' when under anesthesia – though it's a process that could potentially kill him.

  • Body and Mind

    There have been many theories about the body and mind being two different entities. Marcus puts these ideas to the test by taking part in an experiment that will separate body from mind.

  • Brain Response

    One of the smallest parts of the brain, the individual neuron, could be the answer to the question of consciousness, especially when it processes familiar words and images.

  • Conscious and the Unconscious

    Marcus sees how his brain and consciousness are stimulated when he is asleep. However, this proves to be quite difficult.

  • Decisions

    An experiment in Berlin indicates that it could be a part of the brain humans are not conscious of that is responsible for decision making. Marcus investigates further to see if this is the case.

  • Final Summary

    The development of technology and theories can help people understand who they are. However this creates more questions than answers.


Marcus du Sautoy
Executive Producer
Andrew Cohen


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