Monday, September 04, 2006

Dopamine--mystery chemical?

One might question that a fiction writer's blog would delve into a brain chemical--in the realm of fact, and a subject not lending itself to light reading. I'd agree on the light reading part after wading through several articles on dopamine from the Internet. But, as for the realm of fact, I'm not so sure. The Wikipedia leaves many of the properties and information on dopamine's structure and hazards followed by question marks, and the entry begs for shared expertise on the subject.
But, come on, who are we kidding here? Bio-scientific fact is what has brought us diet fads that change year after year as newer studies disprove the most recent ones and often give new vitality to old studies. I just read an article in the Monterey Herald that disputes the whole notion of 8 glasses of water a day. Now, we've known since I was a little girl that you were supposed to drink plenty of water, and suddenly your kidneys can't handle that much? Give me a break!
See, it's fiction, couched in the guise of science. The plot involves making a case for your new break-through and making sure it turns all of our present practices completely around. If it's not entirely true, it may shine a new light on the truth we all know and accept, and give our knowledge a new edge.
Take this water business. I've often wondered what good all that water was doing, since it seems to go straight through me. What if the body needs to receive its water locked into the moist cells of food? In the form of plump lettuce leaves, celery stalks, squash, watermelon, peaches, apples, grapes--to name a few examples. Who would have known? Or rather, all the stress on eating more fruits and vegetables was not just about bio-flavenoids.
But, back to dopamine. I find what I've read so far about dopamine something akin to a mystery novel. Dopamine has to do with the sense of pleasure and reward in the body--not the consciousness of present contentment, but the anticipation of reward. It would be the substance that enables our nervous system to remind us that a steak would taste good, that sex would feel good, that our favorite game would be entertaining. But it also seems to remind us that we enjoy getting together with friends--despite their failings; that learning is rewarding--despite being a challenge; that worship makes raises our spirits--even if it means giving up time we could have used otherwise.
Dopamine seems to help us sustain our expectation of ultimate reward, despite the short-term frustration or boredom we may encounter in the process. This may be why a lack of it is implicated in adult attention-deficit syndrome. ADD sufferers typically find boredom in routine activities and seek novelty, innovation, and activity as a remedy, frequently getting sidetracked from the task at hand.
What we don't seem to know is how much the presence of dopamine in our systems can be increased by outside events or by states of mind. Love and Sex: the Vole Story by Kate Egan, studies the difference peptide hormones such as oxytocin, estrogen, and vasopressin can make in the lives of rodents, and dopamine is associated with these in our bodies as well.
Egan's story points out that the female prairie vole has does not become sexually mature until she encounters a substance from the urine of a male. At that time she goes into estrus and mates with this male, who will become her life partner. In other words, it requires a stimulus from outside her to trigger the process of production and interaction of these substances in her body.
Now, a rodent, presumably, would have no way of conveying to another the idea of what having a mate would be all about. A female vole has no preconceived notion of the male, and her body is dependent on the physical stimulus of the male's own chemistry. But what happens in the case of human beings, who can be stimulated by ideas received from other people, from reading, or from observation? For us thinking is a large part of our motivation. Sure, we're hungry, but it isn't until we see the commercial for the Fruit Loops that we realize that they might satisfy our breakfast longings. For me, the realization that I was prone to hypoglycemia changed my tastes considerably. A sweet breakfast, once the object of my desires, became something to be feared and even somewhat repulsive. In a sense, then, my mind taught my appetite what to like. Conversely, during recent health concerns my chiropractor recommended I increase the percentage of raw foods in my diet. Never one to prefer a luncheon salad to a juicy pastrami on rye, I set upon this course with trepidation, but soon discovered that an enormous salad tasted pretty good. Now I salivate at the thought of my newly developed lunch habit. Again, mind over body.
If this is true, then I am wondering how much a chosen pattern of thinking, based, perhaps, on a voluntary exposure to certain kinds of ideas, can stimulate our bodies/brains to produce the neuro-transmitters that create in us an attitude of well-being, a desire for community, a sense of nurturing towards others. My chiropractor also advised me to repeat affirmations: I am healthy, my body is functioning as it should. I can ignore aches and pains and go for a walk, focusing on the beauty of nature, or for a run, and these activities help me focus on health and wholeness.
Does the monk who chants the psalms seven times daily, recalling the goodness of God, reprogram his brain to also experience that goodness? Does the Buddhist who meditates on thoughts of peace pave the neuro-pathway leading to that peace?
We don't know the answers for sure, but there's enough evidence to keep me interested.