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The Taste of Pain
An anonymous reader writes "The more the human genome is unraveled and previously non-genetic based attributes are now associated with a specific genetic function, such as physical and emotional pain and taste, it seems, to me, that our personalities appear to be much less influenced by out environment and more by our genes." A related article links your sense of taste to your risk for cancer, heart disease, etc.
The taste buds on your tongue are simply sensors, like your eyes, ears, nose, and hands. In fact, taste buds represent the least of all complex sensors of the human body. A taste bud is simply a receptor, waiting to bind to a molecule in solution in your mouth. Once the receptor binds to the molecule, it generates a signal that says, "bitter!" or "sweet!". Combinations of types of "bitter" and "sweet" represent the taste of the food, excluding molecules in the gas phase which are picked up by the nose. I read there were 27 or so types of "bitter" and only two types of "sweet".
Even a human nose is more sensitive than human taste buds. There are over a hundred different types of receptors in the human nose. (And thousands in the dog nose.) Looking at one's ears or eyes, the complexity involved in generating a highly analog signal, over time, and having that signal correctly analyzed is incredible.
And..we are not yet even talking about cerebral functions like reason, imagination, moods, memory, or even behavioral instinct!
Yes, finding the genes that code for the receptors of the tongue is really great. But do not assume that the amazing complexity of the human body, even excluding the brain, will be fully understood for quite a bit of time.
Salis
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It seems to me, on a philisophical note, that as the genome continues to be explored, we will continue to be surprised at what's found. However, the really interesting part will be when the project is finished, and we discover what was NOT found.
_Am
It cannot be completely blamed neither upon genetics or enviromnent. It's a mix.
The body, including the brain, is mostly determined by the genes. The brain is a net of interconnected neurons, that everyone knows. What not everyone knows is that whatever we knows is not actually "recorded" on the neurons, but in the synapsis, that is, the brain interconnections.
We learn and reason mostly by electrical impulses flowing through the aformentioned net. There are basically 2 types of impulses: inhibitive and excitative. The results of a reasoning (that is, initial input everything you can "sense", final output your reaction) depends on how these impulses flow, what depends what sort of impulse reaches each neuron.
The ways these impulses flows depends on each neuron and each neuron is more likely to propagate one sort of impulse rather than the other (e.g 30% chance to propagate inhibitive and 70% excitative). But the sort of impulse that flows through a neuron can make it change its tendency (say, if a neuron gets more inhibitive impulses than excitative, in time the neuron raises its own lilkeliness to propagate inhibitive impulses).
Thus, the learning process depends, initially on two factors: the structure at time 0 (the initial structure, e.g. the brain when you are born) and the structure at the time a person receive the impulses (the brain after experimenting and processing all the impulses one got up to now). That means, genetics influence your behaviour because your brain is biased by the structure it has when you are born, but the environment is the one that provides the impulses, and because the sort of impulses can change the neuron's tendencies, you may not develop some tendencies you had when you were born.
In the end, your personality is a result of what you were in the beginning and by everything that happens. You may have a tendency to kill, but not develop it because a nice environment, and otherwise you may be initially a good natured person, and yet because a bloody murderer if you live in an environment that demands it.
This has linked COMT with a gene. (for those who didn't read the article it "cleans up" after a dopamine chemical linked in sensing pain)
Is it really all that revealing that COMT production is genetically based. Anymore than it is to say insulin production is genetically based.
Regardless, the whole "nature v. nurture" debate is a futile argument when it comes to explaining individual action and the personality that defines those actions.
Esp. when one has a much more reliable and immediate explanation for one's actions, which is to say conscious "choice." Something which we have a much more intimate connection to.
(Sure it's easy to say our conscious choices are mere illusion created from a chain of causation in a reductionist universe... of course doing requires that "illusion" to believe in the reality of reductionism.)
At best genetics and enviorrment are probability guidelines in judging the possible future actions/personalities of an individual. However they are a piss poor way to explain human actions as a whole.
Trying to prove their ideas "scientifically" is an idea that has been taken up by the far left and the far right in the past, and many of the scientific conclusions of both left and right have over time been shown to be ridiculous. On the left you have the Marxist tradition of "scientific socialism" that "scientifically proves" that there is a dialectically material force of history that will lead to the unstoppable triumph of communism. On the right you have eugenics, the Bell Curve, and "science" proving socially darwinistic ideas, and that human behavior is genetically determined. These ideas, both the scientific socialist and eugenic science ideas were very popular in the late 19th century and early 20th century, but time has shown massive gaps in both of these body of ideas, and they both also lead to some extent to the massive exterminations carried out under Hitler and Stalin. But aside from the toll of ideas, is the simple fact that I think time has shown that many of these so-called scientific ideas have a lot of holes in them.
When a scientist points his telescope at the sky, it doesn't really have much of a social effect on earth nowadays (although centuries ago, Galileo Galilei was convicted of heresy for touting the Copernican system, and Giordano Bruno was burned at the stake for his works on Copernican astronomy). When the lens is pointed at humans however, especially human behavior, you are sure that there will be plenty of people grabbing "scientific" research and using it to push their social agendas. So much so, that I have an enormous amount of skepticism about virtually any "scientific" model of human behavior, including psychiatry and psychology. That someone has "scientific" proof of some aspect of human behavior, in this case, that it's predetermined by genetics, really has to be taken with a grain of salt. As do anthropological and sociological studies that show humans are generally better off cooperating and working for the greater good (social anarchism) as opposed to competing (capitalism). These kind of ideas usually break down into left wing and right wing people either supporting or disputing the theories, breaking down among political lines, and so on and so forth, I can't think of anything more unscientific than that. That it's been scientifically proven that "our personalities appear to be much less influenced by out environment and more by our genes" is the epitomy of what sounds like political propaganda - the nurture versus nature debate is an ancient philosophical debate, and from my discussions with scientists who know more about the genome project than I do, they are barely able to use the information they have cataloged to solve medical problems (despite the hype - which is needed for funding), never mind have scientifically set in stone the answer to a fundamental philosophical question about human nature. I take this news with a huge grain of salt.
Why such loaded words? According to the research cited, subjects felt different amounts of pain from the same stimulus. If I feel pain that I'd rate at 6 on a scale of 0 to 10, and after the same stimulus someone else rated their pain a 3, all that says is I am feeling more pain than the other person. It does not say anything about how well I can withstand pain.
It extremely common for people to believe that the same amount of tissue damage causes the same amount of pain for anyone. However, pain researchers knew long before this study that this belief is a fallacy. [Pain: The Science of Suffering by Patrick Wall, Columbia University Press, 2000.]
Perception of pain is a complex event, modified by genetics, culture, experience, anxiety level, perceived purpose of the pain, expected duration, etc. This study is looking at a single variable, and the only thing really interesting is that it suggests that some of the inherited variability is tied to a alleles of a specific gene.
Denise
It is impossible for a man to learn what he thinks he already knows. - Epictetus