My body, my self

24 November 2010

 Attack of the ghost arms
[object Object]

Attack of the ghost arms by Ohhhbetty on Flickr

This Friday, Wellcome Collection hosts an evening spectacular celebrating the wondrousness of the human hand. In the run up to the event, the Wellcome Trust and Wellcome Collection blogs present a series of guest posts by some of those taking part in the event.

Matt Longo is a lecturer in psychological science at Birkbeck in London. His research investigates the mental representation of our body and how this shapes perception, a subject he will present to the public at the Hands event.

Our body is the most familiar object we encounter.  It is, in William James’ immortal words “that same old body always there”.  Like an American Express card, we never leave home without it.  Surely if there’s anything we know like the back of our hand it’s…the actual back of our hand.

Or do we?

Research in cognitive neuroscience has begun to revolutionise our understanding of the human body, how we experience our body, and how it is represented in the brain. Along the way, it’s revealed some surprising findings, showing that we often have surprising poor knowledge about our body and that our experience of our body can be altered by remarkably simple sensory inputs.

For example, anyone unfortunate to have needed dental anaesthesia will know that it makes one feel like one’s mouth has become enormous. Phenomena like this suggest that the continuous signals the brain receives from nerves coming from all over the body make an important contribution to shaping our mental picture of what our body is like, what scientists call the ‘body image.’  Other illusions make people feel like their waist is wider or thinner or even that their nose is extending like Pinocchio’s! Clever measurement techniques have allowed researchers to begin to quantify effects like this and to investigate the underlying brain mechanisms.

My colleagues and I will demonstrate some of these illusions at the Wellcome Collection’s event on Hands this Friday. You’ll be able to experience the feeling that a prosthetic hand is really part of your body, and try out the ‘mirror box’ that allows amputees to ‘see’ their phantom limb. We’ll also explain how scientists are using these illusions to reveal how the mind represents the body, how different senses such as vision and touch become integrated, and how these processes are implemented in the brain.

We hope to see you there. Oh, and don’t forget to bring your body!

Matt Longo

Come and see Dr Longo demonstrate these illusions at the free Hands event at Wellcome Collection this Friday (26 November).