The Tell-Tale Brain: A Neuroscientist's Quest for What Makes Us Human

A caveat is in order. I am not arguing that mirror neurons are sufficient for the great leap or for culture in general. I’m only saying that they played a crucial role. Someone has to discover or invent something—like noticing the spark when two rocks are struck together—before the discovery can spread. My argument is that even if such accidental innovations were hit upon by chance by individual early hominins, they would have fizzled out were it not for a sophisticated mirror-neuron system. After all, even monkeys have mirror neurons, but they are not bearers of a proud culture. Their mirror-neuron system is either not advanced enough or is not adequately connected to other brain structures to allow the rapid propagation of culture. Furthermore, once the propagation mechanism was in place, it would have exerted selective pressure to make some outliers in the population more innovative. This is because innovations would only be valuable if they spread rapidly. In this respect, we could say mirror neurons served the same role in early hominin evolution as the Internet, Wikipedia, and blogging do today. Once the cascade was set in motion, there was no turning back from the path to humanity.

CHAPTER 5

  Where Is Steven? The Riddle of Autism

You must always be puzzled by mental illness. The thing I would dread most, if I became mentally ill, would be your adopting a common sense attitude; that you could take it for granted that I was deluded.

—LUDWIG WITTGENSTEIN

“I KNOW STEVEN IS TRAPPED IN THERE SOMEWHERE, DR. RAMACHANDRAN. If only you could find a way to tell our son how dearly we love him, perhaps you could bring him out.”

How often have physicians heard that heartbreaking lament from parents of children with autism? This devastating developmental disorder was discovered independently by two physicians, Leo Kanner in Baltimore and Hans Asperger in Vienna, in the 1940s. Neither doctor had any knowledge of the other, and yet by an uncanny coincidence they gave the syndrome the same name: autism. The word comes from the Greek autos meaning “self,” a perfect description because the most striking feature of autism is a complete withdrawal from the social world and a marked reluctance or inability to interact with people.

Take Steven, for instance. He is six years old, with freckled cheeks and sandy-brown hair. He is sitting at a play table drawing pictures, his brow lightly furrowed in concentration. He is producing some beautiful drawings of animals. There’s one of a galloping horse that is so wonderfully animated that it seems to leap out of the paper. You might be tempted to walk over and praise him for his talent. The possibility that he might be profoundly incapacitated would never cross your mind. But the moment you try to talk to him, you realize that there’s a sense in which Steven the person simply isn’t there. He is incapable of anything remotely resembling the two-way exchange of normal conversation. He refuses to make eye contact. Your attempts to engage him make him extremely anxious. He fidgets and rocks his body to and fro. All attempts to communicate with him meaningfully have been, and will be, in vain.

Since the time of Kanner and Asperger, there have been hundreds of case studies in the medical literature documenting, in detail, the various seemingly unrelated symptoms that characterize autism. These fall into two major groups: social-cognitive and sensorimotor. In the first group we have the single most important diagnostic symptom: mental aloneness and a lack of contact with the world, particularly the social world, as well as a profound inability to engage in normal conversation. Going hand in hand with this is an absence of emotional empathy for others. Even more surprising, autistic children express no outward sense of play, and they do not engage in the untrammeled make-believe with which normal children fill their waking hours. Humans, it has been pointed out, are the only animals that carry our sense of whimsy and playfulness into adulthood. How sad it must for parents to see their autistic sons and daughters impervious to the enchantment of childhood. Yet despite this social withdrawal, autistic children have a heightened interest in their inanimate surroundings, often to the point of being obsessive. This can lead to the emergence of odd, narrow preoccupations and a fascinations with things that seem utterly trivial to most of us, like memorizing all the phone numbers in a directory.