It’s fascinating reading. The discovery of the plasticity of the brain has only been made possible with the development of various scanning and tomography technologies in the last 25 years; before that it was assumed that the brain is hard-wired and unchanging, once damage has occurred there is no hope.
The initial eye-catcher in the book is the prospect of better physiotherapy for stroke victims, whose chief component of therapy seems to be restraining the good limb, and forcing them to use the bad limbs. The brain then reorganizes its neurons, sometimes rerouting the limb functions through unexpected areas of the brain. When blind people learn to read Braille with their fingers, it was found that the information was processed in parts of the brain used for sight, and spilled into other areas as well.
There exist alternative therapy centres in this country where, by using some form of deep tissue massage, it is claimed that partial functioning can restored to limbs afflicted by stroke. One of my uncles benefited from this, and can now stand and walk. I speculate that the deep massage stimulate the nerves in the affected arm or leg, giving intense signals of touch, pressure, even pain, making the brain aware that the limb still exists. The normal paths in the brain of sensation and command, stimulated by ordinary touch and activated by conscious will were damaged by stroke. In essence, the brain has forgotten that the limb is still there. But the deep massage may send signals through other paths due to the unusual and intense signals generated by the therapy. New pathways may develop in the brain to enable the restoration of function in the limb.
But to me, the best was saved for last in the appendices. One chapter there speculates that culture can reshape the brain, so much so that our brains really are physically different from our preliterate stone age ancestors. It gives for example, the Sea Gypsies of Myanmar, whose culture has reshaped their brains such that they can consciously control the focus of their eyes and see very well underwater (due to the refraction of the water, other peoples will have blurred vision), and also how East Asian people literally think differently from Westerners (holistic vs particular). The latter case was formally assumed to be a case of interpretation only by differing cultures, but scans and studies show real differences in brain functioning.
Likewise literacy literally alters the wiring of the brain. The upshot of this is that cultures and civilizations can lead to different perceptive sensitivities. Cultural activities (reading, music, dance, religion, science, etc) prime the brains of the members, possibly opening up new mental abilities and behaviours.
If one may make an example of the Australian Aborigines, whose culture (at least before its drastic disruption by European arrivals) revolved around hunting-gathering and the Dreamtime belief system. Might it be said that the culture enables them to perceive creatures of the Dreamtime which may not be sensed directly, but by picking up subtle cues in the environment, an Aborigine elder might feel the presence of a Bunyip, say, or other unseen creatures? Some will call it hallucinations or delusions, but maybe… Bunyips do exist, but you have to be “rewired” to sense them… The same rewiring of the brain by their culture also enables them to find resources such as water and edible roots using very subtle signs, that defy normal analysis but come intuitively, neuroplastic reshaping created not just by practical training in the wild but by the rituals, music and tales that create a whole neurological set.
The process may compared to specially tampering with an artificial neural network, such that input weights and biases are preset in some ways and can only be altered in some quantites and directions, leading to skewed training results that are nevertheless useful, exposing strange features in the data being examined that would otherwise go unnoticed.
Theocentric societies may develop other sensitivites, behaviours, and maybe abilities. Recently it was discovered that religion has a biological centre in the human brain. The sensations associated with intense religious and mystical experiences could be activated by electromagnetically stimulating those parts of the brain. Atheists promptly claimed that religion was merely part of human biology… but the flipside of it is, mystics and the great sages have long claimed that there exists in the human special senses that are a gift of the Divine, without which it is impossible to know the Transcendent. The discovery of the brain centres for religious experiences, for the mystic, only reinforces what they have been asserting for thousands of years and can therefore taken to be proof of the existence of Divinity.
Now might it not be that the cultural activities of religious and theocentric civilizations develop and rewire the brain to accentuate this special sense… atheists will say, reinforcing delusion…. but supposing, that the Divine is Real, and that special senses await awakening by the special reshaping of the brain by the surrounding culture…
Alternatively secular Western culture may prime (some of) its members to particularity, analysis and scientific discovery… assuming one can get away from Britney Spears and reality TV…
It might be in the interest of the human race to preserve as many different cultures and worldviews as possible, to cultivate and raise different sensitivities and perceptions. A global monoculture could impoverish human experience.