I read this book in three different positions and each position in a particular angle to the screen. The interesting thing I noticed is that when I changed the usual angle, I was having more struggle to track down the lines and the content and a following significant change in the pace. Over the course of reading, I could see an improvement in reading in different angles which was pretty much proportional to the content of this book, Plasticity. Brain plasticity is truly a gift, which allows us to adapt to a vast range of environments. How fundamentally training shapes and rewires brain is presented in several accounts and in different frames in this book. How neurons and different brain parts operating to shape certain plastic changes are very insightful and interesting facts about the underlying process of our brains.
Plasticity vs localizationism: Plasticity is an almost new field which revolutionized neuroscience and went directly against the localizationism and the notion of hardwired brains. Therefore plasticity is a science that proves not only brain is not like a hardwired structure of circuits, but also it can be rewired over time provided by numerous experimental cases by pioneers of the science of plasticity like Paul Bach-y-Rita, Merzenich, Ramachandran, Schwartz, Pascual-Leone, and etc. Neuroplastic research has shown us that every sustained activity ever mapped—including physical activities, sensory activities, learning, thinking, and imagining—changes the brain as well as the mind.
Plasticity and rewiring: Many tastes we think “natural” are acquired through learning and become “second nature” to us. We are unable to distinguish our “second nature” from our “original nature” because our neuroplastic brains, once rewired, develop a new nature, every bit as biological as our original.
Plasticity and Unlearning: The science of unlearning is a very new one. Because plasticity is competitive, when a person develops a neural network, it becomes efficient and self-sustaining and, like a habit, hard to unlearn.
Different chemistries are involved in learning than in unlearning. When we learn something new, neurons fire together and wire together, and a chemical process occurs at the neuronal level called “long-term potentiation,” or LTP, which strengthens the connections between the neurons. When the brain unlearns associations and disconnects neurons, another chemical process occurs, called “long-term depression,” or LTD (which has nothing to do with a depressed mood state). Unlearning and weakening connections between neurons is just as plastic a process, and just as important, as learning and strengthening them. If we only strengthened connections, our neuronal networks would get saturated. Evidence suggests that unlearning existing memories is necessary to make room for new memories in our networks.
Plasticity and OCD(Obsessive Compulsive Disorder): Schwartz set out to develop a treatment that would change the OCD circuit by unlocking the link between the orbital cortex and the cingulate and normalizing the functioning of the caudate. Schwartz wondered whether patients could shift the caudate “manually” by paying constant, effortful attention and actively focusing on something besides the worry, such as a new, pleasurable activity. This approach makes plastic sense because it “grows” a new brain circuit that gives pleasure and triggers dopamine release which, as we have seen, rewards the new activity and consolidates and grows new neuronal connections. This new circuit can eventually compete with the older one, and according to use it or lose it, the pathological networks will weaken. With this treatment we don’t so much “break” bad habits as replace bad behaviors with better ones.
Plasticity and Pain: Ramachandran developed the idea that pain is a complex system under the plastic brain’s control. He summed this up as follows: “Pain is an opinion on the organism’s state of health rather than a mere reflexive response to injury.” The brain gathers evidence from many sources before triggering pain. He has also said that “pain is an illusion” and that “our mind is a virtual reality machine,” which experiences the world indirectly and processes it at one remove, constructing a model in our head. So pain, like the body image, is a construct of our brain.
Plasticity and Imagination: Whats several “imaginary” experiments show is how truly integrated imagination and action are, despite the fact that we tend to think of imagination and action as completely different and subject to different rules. But consider this: in some cases, the faster you can imagine something, the faster you can do it. Jean Decety of Lyon, France, has done different versions of a simple experiment. When you time how long it takes to imagine writing your name with your “good hand,” and then actually write it, the times will be similar. When you imagine writing your name with your nondominant hand, it will take longer both to imagine it and to write it. Most people who are right-handed find that their “mental left hand” is slower than their “mental right hand.” In studies of patients with stroke or Parkinson’s disease (which causes people’s movements to slow), Decety observed that patients took longer to imagine moving the affected limb than the unaffected one. Both mental imagery and actions are thought to be slowed because they both are products of the same motor program in the brain. The speed with which we imagine is probably constrained by the neuronal firing rate of our motor programs.