Credit: Markku Lahdesmaki/Corbis

If only death were the end of consciousness. But Einstein was right, damn him. I am imprisoned within an Iron Maiden of flesh and bone. My own body is the torture device, reducing me to a blubbering imbecile.

Unable to speak, unable to move properly, unable to understand those around me. Not much better than a cabbage, except for the spark of consciousness within. My mind is intact! I'm still here!

I clench and unclench my fists again, heartbeat pattering in my chest. Looking down causes my head to flop about like a rag doll. My hands are useless – barely controllable.

The hands that once dissected human neural tissue in the finest research laboratory in the world now can't even hold a hammer straight. If this is the natural course of life, then I wish I'd never been born.

The summer sunshine warms my bald head. I breathe in and out, trying for the thousandth time to regain what control I once had. At least my lungs feel clean again.

The smell of the lush green grass I sit on fills my nose. A transitory buzz of a bee makes me forget the hammer and look around in surprise. The noisy insect is gone before I ever see it. Not that I can see properly anyway. Everything more than a metre away seems to blur into double vision. But I have no glasses any more.

My mother is kneeling nearby, looking impossibly young and pretty as she looks after my twin sister and me. How could it be fair that she should look like that?

She smiles at me and picks up the hammer, giving me a demonstration, using it on the piece of wood in a way my hands cannot. Was this supposed to be a lesson from her? Doesn't she realise I am one of the most dexterous neuroscientists who ever lived? No, of course she doesn't.

A bird twitters in the trees behind us. Turning to look makes the world spin as I fall over backwards. Like a turtle on its back, I can do nothing but wave my arms and legs. The grass does smell nice, though. It's cool and fresh against my face. My skin feels so smooth and sensitive to every experience. A tickle in my nose makes me sneeze.

I hear my twin sister giggle. She finds my predicament funny. Yet I know that behind the mask of young flesh she shares my frustration. Neither of us can concentrate on anything for more than a minute or two. Yet we both know we must try before we lose what remains of our sense of selves.

I can see it in her eyes: the sense of loss as more of us slips away each day, making us less and less who we are … were… will be. I know she remembers. Surely she must.

Every day I try to speak, to explain what I know about the nature of consciousness. This is my chance to achieve what my three decades of neuroscience research was unable to. So far my words have all been incomprehensible.

When I finally relearn how to shape my mouth and tongue properly and speak the words I long to say, it will be the biggest scientific breakthrough of all time. From the mouths of babes, they say … well, this time they will be right.

My mother sits me back up again and wipes my nose, which is dribbling. She finds the juice beaker and puts the little spout in my mouth. She finds another for my sister. We both suck noisily. The tart flavour makes us smile together in pleasure. All too soon, my beaker is empty.