A hunt for the self

Introducing "Martin", a man who fully believes he is dead, neuropsychologist Dr Paul Broks says "I had a patient, a very unusual case". Dr Broks' Casebook takes the listener on a psychological and philosophical hunt for "the self", introducing each of the five episodes with an equally fascinating story of an individual whose sense of self is disrupted in some way.

Martin, we are told, suffers from a condition known as Cotard's syndrome. He says he doesn't feel anything at all, his thoughts are not real and that his brain has rotted away – a real-life zombie if you like. Adam Zeman, Professor of Neurology at Exeter University, is brought in to explain what might be going on. One of his patients, Graham, has also been diagnosed with Cotard's syndrome and is so convinced he is dead that he hangs out in graveyards. Further investigation with neuroimaging reveals that his brain is behaving like that of someone who is in a coma – he has markedly less activity in the 'default mode network', a series of brain circuits that allows us to reflect on the past, imagine the future, and experience the now.

So, the producer asks, does this mean we've found the self? Dr Broks explains that the answer is not that simple and over the next four episodes he introduces us to Natalie, a woman who has a sudden onset of psychogenic amnesia and doesn't know who she is any more; Laura, who suffers from sleep paralysis and experiences terrifying visitations at night; Joe, a man who experiences dramatic 'out of body experiences' as a result of his epilepsy; and Jason, a young man with anarchic hand syndrome, a condition in which one hand seems to behave outside of conscious control, stubbing out cigarettes or fighting the other hand.

Throughout the series, Dr Broks calls upon an impressive panel of experts – Adam Zeman, Andrew Mayes, Chris French, Peter Halligan, Michael Gazzaniga – and together they explore the neurological, psychological and philosophical approaches to defining and locating the sense of self. What role does the ego play? Where are the boundaries of the self? How does sense of self change through different stages of sleep and after brain injury? What can we learn from phantom limbs?

Every episode is compelling, entertaining and informative in equal measure and while each of these questions are answered, Paul Broks concludes that maybe we shouldn't think of the self as a unified entity and questions whether it even exists. So has he failed in his quest? I don't think so. Adam Zeman probably summarises it most accurately and succinctly when he says, "the self is represented countless times in the brain in a whole variety of different ways – it is everywhere and it is nowhere."