15 March, 2010

V.S. Ramachandran @ Union Theatre, 10 March 2010


(Photo from The Daily Cardinal.)


V.S. Ramachandran swung through town last week and gave a speech at the Union Theatre on Wednesday. Being a neurologist, he spoke about some ideas on how the brain works and completed a trifecta of speakers this season who offered insights on cognition and how and why people think what they do. (The others were Dan Ariely and Michael Shermer.) Ramachandran's concerns were less behavioral and more about the nitty gritty of grey matter – all those synapses, neuron, and the like.

He began by saying that his field likes to examine people who had changes in their brains. When he said this, I automatically thought of Phineas Gage, that railroad worker who got an iron rod shot through his brain in an accident involving blasting powder and, although he survived, was never the same person again. But Ramachandran avoided such incidents in his talk and instead focused on three topics: 1) phantom limbs, 2) synesthesia, and 3) mirror neurons.

Phantom limbs refers to the sensations people have of limbs that have been lost. Amputees report that, although their limbs are no longer there, if still feels like they are and somewhere between 2/3 to ¾ of people with phantom limbs feel great pain so studying them is no mere academic exercise. V.S. explained how he was able to get a patient, as he jokingly put it, to move his phantom limb. First he noted that copies of brain commands to move muscles were sent to the cerebellum so that the brain can monitor movement. Then he told of how the man tried every day to "unstick" his phantom limb to no avail. VS was able to rig a mirror to create the illusion that the severed limb was back and, lo and behold, the visual stimulation enabled the patient to "move" the phantom limb. VS said that no one gets awards or funding for getting someone to move a phantom limb so he talked about this kind of treatment for stroke victims.

This subject led into a brief discussion of mirror neurons. Work by Giacomo Rizzolatti and others has shown that the mirror neurons of monkeys fire when watching other monkeys perform actions. And so, when monkey A is watching monkey B grab a banana, the neurons in monkey A's brain which would fire to induce those same muscle movements do indeed fire but don't produce the movement. VS said there is evidence that we humans have these same mirror neurons as well. Relating this back to his first topic, he said that people with phantom limbs can only feel touch in them by watching the actions of others. This led to my hypothesis that my friend Marv, who was also in attendance, could only feel touch in his phantom penis when watching other men…well, you get the idea. The benefits of science are many although Marv might not be so enthusiastic about this.

Puerile jokes aside, I never knew that so many people with phantom limbs felt such great pain. I can imagine such research is of tremendous importance - the many soldiers coming home from Iraq and Afghanistan who have lost limbs sprang to mind as I sat there.

The final topic of his lecture was about synesthesia, which is a sensory phenomenon where one type of input triggers an unrelated response. VS focused on the variety involving colors and numbers whereby some people would see a numbers as a color but he also noted those who got certain tastes in their mouths after touching certain textures. Interestingly, Roman numerals didn't do it, only Arabic ones. This and other evidence pointed to the parts of the brain responsible for dealing color and shape are in close proximity to one another and that they are connected in synesthetes to a greater degree than in those who do not have synesthesia. Ramachandran finished by talking about metaphor. He told us that schizophrenics are unable to comprehend metaphor and instead take everything literally. By way of example, he quoted Shakespeare: "Juliet is the sun!" A schizophrenic would be aghast to learn Bill thought a person was a blazing hot ball of gas but we "sane" folks get it. Perhaps metaphor, like synesthesia, reflects how the various parts of our brains are connected to one another.

And that was a major theme of the lecture. While the various parts of the brain may specialize in particular functions, there is a lot of overlap.

VS called the brain the "most complexly organized matter in the universe". Our grey matter is, if you'll pardon the expression, truly mind-boggling.

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