I would like to tell you about the
most powerful computers on the face of earth, maybe in the entire universe.
Those who know me can guess that I am referring to the humid, squishy, pinky,
convoluted material apparently messy and not very elegant, that most of us wear
hanging in between our shoulders and above our noses. Our brains. The famous
British writer Oscar Wilde sentenced: “The great events of the world take place
in the brain”. Our brains allow us to communicate, to think, to feel, they
enabled our ancestors with the ability to distinguish friend from foe, to
search for food, they allowed us to develop mathematics and prove Fermat’s
theorem among many others, to synthesize antibiotics, to go to the moon and to
explore other planets and also to fabricate those artificial and rudimentary
computers that are so entertaining to us. Our brains have changed the course of
natural evolution.
How is it possible that a soft
biological tissue, composed of nothing more and nothing less than moving
organic and inorganic molecules, can give rise to the magic of cognition? The
fundamental basis for the study of the brain was established by a Spaniard,
Ramon y Cajal. A giant. He wanted to become an artist. His parents told him “no
way” and forced him to study medicine. He combined tradition and passion by
devoting his life to observing and drawing the main cells of the brain: the
neurons. The secret of the brain is hidden within the complex neural networks
that connect millions of neurons. Our memories, our decisions, our feelings are
codified in the patterns of connection and communication among neurons.
Let us consider an example. What
does it mean to see and recognize the face of a friend? Light is reflected in
that face and reaches our eyes, our retinae, and is converted into electrical
signals, almost like pixels in a digital camera. From there, those electrical
signals travel, in a binary format, essentially fancy sequences of zeros and ones,
moving at enormous speeds, passing from one neuron to another, extracting
relevant features from that face, and transforming those pixels into new codes,
new formats and thus building a reality, an interpretation of the world. What
we perceive is nothing more and nothing less than our interpretation, our own
way of building our internal world in a code formed by zeros and ones. In a
small fraction of a second, in less time than it takes to blink, we can compare
those electrical pulse sequences with our memories and recognize the person in
front of us.
This may not seem too surprising.
After all, any kid can recognize his family and friends without having to study
advanced calculus. And yet, those other computers, the artificial ones, still
cannot do this very well. In fact, those tasks that seem difficult to us, such
as computing the square root of 7 are very easy to execute for artificial
computers. In contrast, those common sense tasks that are so intuitive to us
such as identifying a friend and understanding their jokes, can be extremely
difficult to teach to an artificial computer.
During the last couple of years, we
have developed new tools that enable us to interrogate the brain at
unprecedented resolution. We are beginning to characterize and describe the
neural circuits within our brains in a large scale. Maybe in the not too
distant future we may have brain diagrams similar to the ones used by
electrical engineers to design computers. We are also beginning to listen how
ensembles of neurons converse with each other. Elucidating how the brain works
is changing history. Understanding neural circuits will enable us to alleviate
the devastating conditions that afflict the brain. Imagine a world without
Parkinson’s disease and without Alzheimer’s disease. Deciphering the biological
codes in neuronal circuits will also enable us to build robots that are smarter
than us, with tremendous consequences in almost every domain. Imagine a world
where robots can paint better than Picasso, compose more beautiful music than
Bach and develop theories better than Einstein. The first ultra-intelligent
machine is the last invention that man need ever make. Because that machine
will be able to make the rest. And perhaps more importantly, decoding the magic
of cognition will allow us to understand who we are.
