How is the mind shaped?
L-R: The infinite potential of the human mind. Human mind is shaped by genes and the experiences.
In shaping the mind and brain, the debate about nature versus nurture, biology versus culture, genes versus environment remain unresolved. To some researchers, the idea that the spirit might exist apart from the body is just ridiculous. According to them, genes shape environment and brain chemicals shape behavior. The consciousness is created by the neuronal assembly, the organized fashion of the nerve cells which constitute the entire nervous system including the brain. To them, free will is just an illusion and human beings are nothing but "hard-wired" individuals preprogrammed to do this or that. But how is it possible for the 30,000 genes to make a brain with billions of neurons and encode the particular aspects of cognition that make us human? A field called epigenetics has finally begun to address this issue, at least to some extent. It tells us how tiny molecules stick to or become unstuck from two main targets of a cell's nucleus- the DNA in and around a gene and the histones- the proteins around which chromosomes spool. The tiny molecules are known as methyl and acetyl groups whose presence or absence at target sites control whether particular genes will create proteins, which are then responsible to carry out the physiological processes, in most of the cases. This brings into light, the idea, that activity of the genes can be directly controlled by the environment and the process is known as epigenetic control. It says that, when we change our perception on beliefs, we send totally different messages to our cells and thus reprogram their expressions. However, things are not as simple as that. Though every cell of our body is innately intelligent, they function in cohort in the multicellular organization having as much as eighty trillion cells. This cohort generates a "central voice"- a character we perceive as the mind and the spirit. If we look at the developmental processes of the brain, we would see that nerve cells in the developing cells crackling with purposeful activity. Like teenagers with telephones, cells in one neighborhood of the brain are calling friends in another, and these cells are calling their friends, and they keep calling one another over and over again, "almost, as if they were autodialing", says University of California, Berkeley neurobiologist Carla Shatz. During the first years of life, the brain undergoes a series of extraordinary changes producing trillions more connections between neurons, shortly after birth, than it can possibly use. Then, through a process that resembles Darwinian competition, the brain eliminates connections, or synapses, that are seldom or never used. Nature is the dominant partner during this phase of development, but nurture plays a vital supportive role. When Eric Kandel, Columbia University neurophysiologist observed the twin processes of learning and memory in giant snails by blocking the activity of a protein CREB, he found that they could still learn but could not remember. And without forming long term memories, learning process fails. "Nurture is important," says Kandel. "But nurture works through nature." Researcher Steven Cole of the University of California, Los Angeles, and his colleagues found that chronic loneliness triggers a change in gene activity. Again, physical training helps a person to become stronger, fight mild depression, lose weight, lower blood pressure, and to have more efficient heart and brain. The "anxiety gene" raises the risk of depression only when an individual faces difficult life circumstances which again illustrate the importance of an interaction between genes and the life experiences. Richard Dawkins once challenged readers "to teach generosity and altruism, because we are all born selfish." But we know altruism exists among people and we are not by born egoists. Perhaps we are born with the potential to be selfless and environmental interactions actually trigger the altruistic behavior. All of this affirms the notion that we live in a world of conscious choice gaining experiences from the environment. Conscious awareness, indeed, can actively transform the character of our lives into ones filled with love, health and prosperity rather than being hard-wired individual with particular sets of genes.
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