延续: 会改变自己的脑

Appendix 1: Culture & Brain

Culture modifies brain, and vice versa. Culture is not just produced by the brain; it is also by definition a series of activities that shape the mind. We become cultured through training in various activities, such as customs, arts, ways of interacting with people, and the use of technologies, and the learning of ideas, beliefs, shared philosophies, and religion. So a neuroplastically informed view of culture and the brain implies a two-way street: the brain and genetics produce culture, but culture also shapes the brain. As Merzenich put it, "Our brains are vastly different, in fine detail, from the brains of our ancestors..."

Sea gypsies

There is an example, sea gypsies. Due to their environment and lifestyle, they learn to swim before they learn to walk, and live over half their lives in boats on the open sea. By learning to lower their heart rate they can stay under water twice as long as mot swimmers. The Sulu(tribe) people can eve dive over seventy-five feet for pearls without diving equipment. Furthermore, the gypsies can see clearly at these great depths, without goggles. They learned to control the size of their pupils. This is a remarkable finding, because human pupils reflexively get larger under water, and pupil adjustment has been thought to be a fixed, innate reflex, controlled by the brain and nervous system.

Brain Structure

Brain imaging shows that musicians have several areas of their brains- the motor cortex ans the cerebellum, others-that differ from those of non-musicians. The changes not only happen in cultured activities. Taxi drivers who spend more time navigating the street, have the larger volume of hippocampus, that stores spatial representations. Meditators have a thicker insula, activated by paying close attention. Human beings did not evolve to see clearly under water- we left our "aquatic eyes" behind with scales and fins, when our ancestors emerged from the sea and evolved to see on land. Underwater sight is not the gift of evolution; the gift is brain plasticity, which allows us to adapt to a vast range of environments.

Primitive brain meets Modern brain

Our hunter-gatherer ancestor's brain has the same basic brain modules and as plastic as our own. Modular change is necessary for adaptation to the modern world, which exposes us to things our ancestors never had to contend with. An fMRI study shows that we recognize cars and trucks with the same brain module we use to recognize faces. That's why we recognize colors before shapes, sounds before words. 30, 000 years ago humanity learned to draw on cave walls, which required forming and strengthening links between the visual functions and the motor function. Then, hieroglyphics were invented. Next, these hieroglyphic images were converted into letters, and the first phonetic alphabet was developed to represent sounds instead of visual images.

The missing link of Darwin Theory: Plasticity

Our Animal Instinct

As human beings, it is possible for us to mix together brute predatory and dominance instincts(intelligence). An activity of this kind is called a "sublimation," a hitherto mysterious process by which brutish animal instincts are "civilized." How sublimation occurs has always been a riddle. Clearly, much of parenting involves "civilizing" children by teaching them to restrain or channel these instincts into acceptable expressions, such as art, computer games and sports. In aggressive sports such as footballs and boxing, fans often express these brute  wishes ("Kill him! Eat him alive!"), but the civilizing rules modify the expression of the instinct, so the fans leave satisfied if their team wins enough points. However, the most ancient and darkness human instinct is killing. War has becoming the unchangeable culture throughout history in every race. 

Caught between two culture: acculturation(additive), immigration, mass rewiring, culture shock is brain shock, natural and second nature.

Sensing and Perceiving: Interpretations, perceptive, analytically, holistically
Where people in one culture differ from those in another in their beliefs, it can't be because they have different cognitive process. Rather, they must have been exposed to different aspects of the world, or taught different things. Culture can influence the development of perceptual learning because perception is not a passive process. The perceiving brain is active and always adjusting itself.

Brainwash and social rigidity

Human beings can be broken down and then develop, or at least "add on," neurocognitive structures, if their daily lives can be totally controlled, and they can be conditioned by reward and severe punishment and subjected to massed practice, where they are forced to repeat or mentally rehearse various ideological statements.

For every hour of TV the toddlers watched each day, their chances of developing serious attentional difficulties at age seven increased by 10%. Erica Michael and Marcel Just of Carnegie Mellon University did a brain scan study which shows different brain areas are involved in hearing speech ans reading it, and different comprehension centers in hearing words and reading them.  Listening to an audio book leaves a different set of memories than reading does.

Each medium(radio, tv, internet) leads to a change in the balance of our individual senses, increasing some at the expense of others. The written word moved preliterate man from a world of sounds to a visual world, by switching from speech to reading; type and the printing press hastened that process. Now the electronic media are bringing sound back and, in some ways, restoring the original balance. Dopamine is released during playing computer games so people who are addicted to computer games show all the signs of other addictions: cravings when they stop, neglect of other activities, euphoria when on the computer, and a tendency to deny or minimize their actual involvement.

Television, music videos, and video games, all of which use television techniques, unfold at a much faster pace than real life, and they re getting faster, which causes people to develop an increased appetite for high-speed transitions in those media. We have acquired a taste for it and find slower changes boring. The cost is that such activities as reading, complex conversation, and listening to lectures become more difficult.