Are you longing for your brain and all its memories to be preserved for ever? That once fanciful idea seems creepily closer now that a complete pig’s brain has been successfully treated, frozen, rewarmed and found to have its neural connections still intact. This achievement, by the cryobiology research company 21st Century Medicine (21CM), has just won the final phase of the Brain Preservation Foundation’s prize – a prize that demanded all of a brain’s synaptic connections be preserved in a way that allowed for centuries-long storage of the entire information content of a whole large mammal’s brain.

They used a pig’s brain, which was perfused with lethal glutaraldehyde before being frozen at –135C, a method called aldehyde-stabilised cryopreservation (ASC). This process kills any chance of the brain being brought to life again, but they won because when the treated brain was warmed up again its connectome – the brain’s wiring diagram – was amazingly well preserved. In fact it was so well preserved that even the fine ultrastructural details of dendritic spine synapses could still be seen with a 3D electron microscope. This means potentially 150 trillion connections, all of which may be implicated in storing memory.

A human brain treated this way could never be brought back to life. Yet all its preserved information could potentially be uploaded into an artificial or virtual body indistinguishable from the previously living one – like “uploading a person’s mind” after a long wait. Would this then be “you”?

A few years ago I was asked to become an adviser to the foundation. At first I adamantly refused, but they persuaded me that they needed doubting sceptics as much as enthusiasts and I soon realised that brain preservation raises deep questions about mind, consciousness and self that interest me greatly.

My friends, family and old connections would be gone. No one would understand me and I would not understand them

My doubts have not gone away. They partly concern overpopulation and unfairness – what a horrible world it would be in which rich old people could have their minds uploaded, taking resources from younger people on an already overcrowded planet. What hubris for anyone to think their brain is worth preserving when everyone else’s is not. But I have much deeper doubts.

What is a mind anyway? We are far more than just brains and stored memories. We are whole embodied humans, deeply embedded in social worlds. Who am I? I am partly a product of my communications with everyone else. If my brain were preserved today and used in a brilliantly natural-seeming artificial body in a year’s time, then I might indeed wake up and go, “Wow, here I am again”, and take up my old friendships, family connections, email habits, website and Facebook page and still feel that I was the same person – just with a bit of a gap in time like being ill or going travelling for a year. But what if this were done a century hence – when the technology matures?

The world is changing ever faster and so are our “selves”. Each of us is connected with large groups of people in ways that were impossible only a few years ago. We rely heavily on external devices to explore the world and tell other people about ourselves, so that who I am is already becoming my output stream and the way it’s taken up and passed on by others – in other words, the memes that make up “me”. If, as philosopher Daniel Dennett suggests, a person is “an ape infested with memes”, then the nature of persons will inevitably change as technology and artificial intelligence evolve ever faster.

My guess is that “I” would wake up in my new, perfect artificial body and think, “Wow, here I am again”, only to realise that I was a completely inadequate “person” in this new world. Everyone else’s minds would be so far expanded beyond their original brains into other devices, implanted and external, that they would see me as a profoundly backward human or some kind of throwback from a primitive world they could hardly imagine. My friends, family and old connections would be gone. No one would understand me and I would not understand them.

This is one more reason why I shall not be signing up for my own brain preservation any time soon.

• Sue Blackmore is a freelance writer, lecturer and broadcaster