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In the movie Self/Less, which hits theaters July 10th, Sir Ben Kingsley transfers his
consciousness to Ryan Reynold’s body in an effort to stay alive forever, and effectively
become immortal in a process called ‘shedding’. Which sounds pretty awesome – I mean who
wouldn’t want more time to accomplish their dreams and goals in a younger body of your
choice? Try being a professional athlete or solve the world’s greatest problems. But
is shedding actually plausible? Could you really be immortal in this way?
First, we need to understand how memories are stored. Your brain is a three-pound lump
of fatty tissue that contains about 86 billion brain cells called neurons. By passing electricity
or chemicals between them, neurons can send signals to each other. Most neuroscientists
believe memory is stored as a network of neurons that form links with each other and all fire
at the same time. Each time a memory is recalled, the same network of neurons fires together.
In fact, scientists have shown that if you stimulate certain parts of the brain with
electricity, you can cause an individual to recall certain memories - for example, the
smell of burnt toast.
So to download a memory, we could simply track which neurons are activated when you’re
thinking about it. And, as we explained in a previous video, scientists have already
done this. By using computers to match these patterns of firing neurons with real images
or scenes, we can already read people’s minds to a limited degree.
Many scientists believe it should one day be possible to create a kind of map of all
the neurons in the brain and the connections between them: this map would be called a “connectome.”
Both the United States and the European Union have launched major research programs with
this goal specifically in mind, much like the organizations in Self/Less. This task
will likely take decades, but once it’s done, scientists should be able to build a
computer model of the connectome, a kind of virtual brain that would be able to send signals
between neurons through artificial synapses.
So if downloading memories is possible, what about uploading? That too is becoming a reality
thanks to a technique called optogenetics. This involves injecting specific neurons with
DNA from algae that causes them to produce a light-sensitive protein on their cell surface.
When light is shone into the brain, it stimulates the protein and activates only those neurons
that express it. In this way, scientists can artificially activate groups of neurons associated
with particular memories.
All this may sound pretty scary, and may make you think that a scenario like that found
in Self/Less can’t be far off. But there a few reasons to relax.
Our brains are unbelievably complex, perhaps too complex to copy. The number of synapse
connections is a thousand times bigger than the number of stars in the Milky Way galaxy.
On top of that, your brain is constantly remodeling itself, creating new connections and letting
old ones expire. It’s a reflection of who you are at this specific moment in time, and
it took your entire lifetime to create.
A copy of your mind would be just an imitation. And the second it started integrating new
thoughts, memories and experiences, it would become someone else. Which, in a way, helps
us appreciate how unique we truly are. But with increasingly sophisticated technology,
who knows what the future may hold! Perhaps a world like Self/Less isn’t too far away.
Be sure to check out Self/Less which is in theatres July 10th - we’ll be there and
are excited to hear what you all think.
You can click on the screen or use the link in the description to get a sneak peek of. And subscribe, for more weekly science videos.