Saturday, March 29, 2008

E2.0: V.S. Ramachandran: Bridging Humanities and Science

This is the 28th in a new series of weekend posts taken from the presentations at the Salk Institute’s “Beyond Belief: Enlightenment 2.0.”. I have placed an index of essays in this series in an introductory post, Enlightenment 2.0: Introduction.

V.S. Ramachandran came to the Beyond Belief 2 conference to support the idea that studying the brain can give us insights into aspects of culture by giving us a specific example. Specifically, he wants to argue against the idea that there are two fields of study – science and humanities, and that there is a fundamental difference between them. By studying the brain, he argues, we can link science and culture.

To illustrate this point, he intends to draw a line from a subject of brain study (synesthesia) to an aspect of culture (metaphor).

Synesthesia is a phenomena where (in the form that Ramachadran talks about) the agent sees numbers as being colored. Show him a number ‘5’ and he will see it as green, for example. The number ‘2’ will appear as red.

With something strange like this, Ramachandran takes it as his first challenge to show that this is real. He does this with a simple experiment. He takes a screen and covers it with the number ‘5’, except for a few instances of the number ‘2’. He then asks the subject of the experiment to tell him the shape that the ‘2’s’ form on the screen. Most people take a fair amount of time to identify the 2’s and to make out the shape that they form. Synesthedes, on the other hand, see the shape almost immediately – almost as easily as the rest of us would if the 2’s and 5’s were of sharply different color.

Okay, the phenomenon is real. Is it a visual phenomenon, or is it associated with the higher concept of a number? To show that it is visual, researchers show the subject a Roman numeral (e.g., a V for 5). The subjects report that there is no color. Or, they show the subject a large number 5’s made up of the number ‘3’ repeated over and over. Subjects who focus on the individual 3’s see one color, but see another color when they look at the overall image of the 5.

Ramachandran reports that they have come across higher-level synesthedes who do associate colors with number concepts such as the Roman numeral 5. That will become relevant later. For this initial account of the phenomenon, we are focusing on what is called grapheme -> color synesthesia.

There are some additional observations that Ramachandran introduces in order to improve our understanding of this quirk.

For example, synesthesia runs in families. This, of course, suggests that there is a genetic component. Somewhere, there is a gene, or a set of genes, that are responsible for some form of brain change that causes people to see colors when they see numbers.

Another piece of information relevant to our understanding is that the two relevant parts of the brain – the part that is used in the visual recognition of numbers, and the part that is used in the processing of colors, are right next to each other in the brain. As such, it is possible for a signal that gets sent to the part of the brain that recognizes the shape of numbers to leak over into the part that processes colors. The visual recognition of the shape of a ‘5’, in this case, could leak over and trigger a sensation in the part of the brain that processes colors of the color ‘green’.

A third relevant fact is that the brain of an infant contains far more connections than we have. During brain development, a number of connections get pruned away, which actually explains how we learn so rapidly in the first years of our life. It is not caused by forming new connections, but by getting rid of the noise in the brain that gets in the way of our ability to think.

So, we combine these three facts and then we ask a question. What would happen if there were some gene or combination of genes that affected this pruning process – preserving links between different parts of the brain that pruning would otherwise isolate from each other? Such a characteristic would preserve links between the section of the brain that processes number shapes and the section that processes colors, causing grapheme -> color synesthesia.

Now we have a theory that links several facts. From this theory we can draw additional implications, which then can be used to generate predictions, which can be used to verify or falsify the theory.

I mentioned above that there are other types of synethedes. There are forms that link sound to color, that link number-concepts to points in three-dimensional, that link days of the week to personality types.

So, let us suggest that this ‘lack of pruning’ that takes place is more general – affecting all parts of the brain. People who have this genetic characteristic, then, not only are in the habit of associating numbers with colors, but can potentially link any concept with any other concept.

Ramachandran wants to suggest that a synesthede would be particularly good at metaphor. He specifically uses Shakespeare’s example, What light through yonder window breaks It is the East and Juliet is the sun Arise, fair sun, and kill the envious moon. Who is already sick and pale with grief…

Another observation that Ramachandran has encountered in his research is that sunesthesia is about eight times more common in artistic types such as authors and poets as it is in the general population. The idea here is that, if this theory is correct and synesthesia is caused by diminished pruning of connections in the brain, itself allowing sections of the brain to be connected that would have otherwise been broken, then synesthedes would be better at metaphor than the general population. They simply think in terms of associations (like the association between numbers and color) that the rest of us do not have access to.

Ramachandran would be the first to acknowledge that additional work needs to be done. This is not yet a smooth and unbroken link from genetics to an aspect of culture (artistic ability). It is, however, a hint at the types of things that brain research may reveal. It does at least hint at the possibility that we can introduce some science into the humanities.

It is easy for Ramachandran to convince me that there can be a link between brain structure and the humanities because I already buy into the bedrock concepts on which such a claim is built. I have long argued for a link between biology and ethics – though I also hold that a great many evolutionary psychologists and moral psychologists are looking at the wrong parts of biology that significantly diminishes the quality and the importance of their work.

This is illustrated in an important question about synesthedes that Ramachandran simply avoided asking. Is this ‘quirk’, as he called it, a mental defect, or is it a special gift, or is it neutral (neither good nor bad). He mentioned how it is important that at least some of us in society not be too creative. For example, he claimed that we do not want a brain surgeon working on us to suddenly get creative. However, it may be useful to have some of us be creative, and that is why we have a genetic quality that affects only some of us.

This is a question of value. To determine whether a particular part of our mental functioning is an illness, or a gift, or neither, we must measure the value of that trait. The only way to measure value, I argue, is to measure the degree to which a trait will tend to fulfill or thwart desires – and, in particular, whether they will fulfill or thwart good desires. A mental quirk is not an illness or a defect merely because it is rare. In order to be a defect, it must thwart desires.

In this study, I could not see much of a reason to consider synesthesia to be desire-thwarting. In fact, it seemed effective at desire-fulfilling. It is something we have no reason to discourage, even if we do not have a particularly strong reason to promote.

This, then, is how we can at least start to link the humanities to science.

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