Adventures in Behavioral Neurology: What Neurology Can Tell Us About Human Nature
So here is something staring you in the face, an extraordinary syndrome, utterly mysterious, where a person wants his normal limb removed. Why does this happen? There are all kinds of crazy theories about it including Freudian theories. One theory asserts, for example, that it’s an attention seeking behavior. This chap wants attention so he asks you to remove his arm. It doesn’t make any sense. Why does he not want his nose removed or ear removed or something less drastic? Why an arm? It seems a little bit too drastic for seeking attention.
[V.S. RAMACHANDRAN:] I’m interested in all aspects of the human mind, including aspects of the mind that have been regarded as ineffable or mysterious. The way I approach these problems is to look at patients who have sustained injury to a small region in the brain, a discipline called Behavioral Neurology or Cognitive Neuroscience these days.
Let me tell you about the problem confronting us. The brain is a 1.5 kilogram mass of jelly, the consistency of tofu, you can hold it in the palm of your hand, yet it can contemplate the vastness of space and time, the meaning of infinity and the meaning of existence. It can ask questions about who am I, where do I come from, questions about love and beauty, aesthetics, and art, and all these questions arising from this lump of jelly. It is truly the greatest of mysteries. The question is how does it come about?
When you look at the structure of the brain it’s made up of neurons. Of course, everybody knows that these days. There are 100 billion of these nerve cells. Each of these cells makes about 1,000 to 10,000 contacts with other neurons. From this information people have calculated that the number of possible brain states, of permutations and combinations of brain activity, exceeds the number of elementary particles in the universe.
The question is how do you go about studying this organ? There are various ways of doing it. These days brain imaging is very popular. You make the person perform some task, engage in conversation or think about love, for that matter, or something like that, or imagine the color red. What part of the brain lights up? That gives you some confidence in saying that that region of the brain is involved in mediating that function. I’m sort of simplifying it, but something along those lines. Then there is recording from single cells where you put an electrode through the brain, eavesdrop on the activity of individual neurons, find out what the neuron is responsive to in the external world. There are dozens of such approaches, and our approach is behavioral neurology combined with brain imaging