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The Brain That Changes Itself Norman Doidge M.D. Chapter 11 –“More Than the Sum of Her Parts – A Woman Shows Us How Radically Plastic the Brain Can Be”

In Chapter 11, Dr. Doidge introduces us to Michelle Mack, a 29 year old who was born with only the right hemisphere of her brain. At birth, her doctors were not aware of this and now that they do know, they only have theories of what happened before birth. In order for Michelle to function well, her right hemisphere had to learn the function of the left hemisphere and economize its own function. At 29 she holds down a part time job and enjoys her family. There are some outwards signs of her lack of a left hemisphere: bent, twisted right hand that can be used for some things; brace on right leg; she is a lefty and her left limbs are normal. Her right visual field is limited as she has a hard time seeing things coming from her right. Blindness on her right side has helped her develop an extremely keen sense of hearing. Thus she can experience sensory overload in her hearing and touch.

During pregnancy, Michelle’s mother had some difficulties and apparently her body was trying to miscarriage. Both mom and daughter are happy it didn’t. Michelle’s parents began to notice things that indicated developmental problems – vision, motor. They noticed that she was tracking visually so she was not totally blind. Her dad noticed that she likes music and wanted to hear certain music over and over. He had her crawl to the record player to earn listening again. This helped develop her brain and function.

Michelle explained to Dr. Doidge that she would use rhyming, nonsensical words when frustrated. Concrete thinking is much easier than abstract thinking. She can play Solitaire very quickly because the decisions are very concrete. Other, more abstract decisions are more difficult for her.

Michelle demonstrated savant abilities. She could tell what day of the week a date was within the last 18 years by memory. For those dates before that time, she would have to figure it out, but still could do it quickly and accurately. Doidge told her about the work of Alexandr Luria, a Russian neuropsychologist with a memory artist who had a photographic memory. Also, he told her about “synesthetes” whose senses were “cross-wired” so that they had a color code for days of the week. Michelle said she had a scene connected with days of week.

Dr. Jordan Grafman, the chief of the Cognitive Neurosciences section of the National Institutes of Health, National Institute of Neurological Disorders and Stroke has been working with Michelle Mack. His background includes working with a woman whose brain was damaged in an assault. After five years, other doctors had given up on increasing this woman’s function. However, Grafman began an intensive program of rehab – mind and body –and the woman’s function increased. He also served our military personnel in Viet Nam. In this case as well, he saw increase in function where none was expected. He formulated a theory integrating “nondoctrinaire localization and plasticity. His research revealed four kinds of plasticity.

1)       “Map Expansion” – neurons in the center of an area focus more on a task than the ones on the outer limit. Different areas compete for those peripheral neurons. The greater the demand the more likely the use for that area.

2)       “Sensory Reassignment” – When one sense is blocked, another area takes over the function of the blocked sense. In blindness, the senses of hearing or touch develop more and are keener.

3)       “Compensatory Masquerade” – once explained as “alternative strategies” when there is more than one way to do something.

4)       “Mirror Region Takeover” – this occurs when a part of one hemisphere fails to do its job, the mirror region on the other side takes over the function as well as it can. When the damage occurs before specialization develops, function approximates “normal” more than when it is later. P. 276 This is true for Michelle, the damage was before birth, while her brain was being formed.

Michelle’s parents are making preparations for Michelle’s care after they are gone, but she is pretty happy the way she is. Doidge again introduces a person and researchers as windows into the plasticity of the brain.

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The Brain That Changes Itself – by Norman Doidge, M.D. Chapter 7 “Pain – The Dark Side of Plasticity”

In Chapter 7, Doidge introduces us to an M.D. whose specialty is neurology, but who also has a Ph.D. in psychology. Though from India, Ramachandran directs the Center for Brain and Cognition at the University of California in San Diego. Using simple devices “Rama” has discovered the secret of phantom limbs and chronic pain. Some people suffer pain even after organs have been removed. “Normal pain, ‘acute pain,’ alerts us to injury or disease by sending a signal to the brain saying, ‘This is where you are hurt – attend to it.’”(p. 180) When the nerves themselves are damaged ‘neuropathic’ pain results with no known cause.

Reading the work of Tim Pons and Edward Taub regarding mind mapping monkeys, Ramanchandran wondered if neuroplasticity would explain phantom pain. “Rama” worked with a 17th year old amputee. First, by blindfolding the young man and then with brain mapping (magnetoencephalography), he was able to determine that the brain map for his phantom arm and face had merged. Some relief was enjoyed by satisfying an itch in the phantom arm by scratching his face. Taub’s team and others have confirmed “Rama’s” conclusion. All of this is so unpredictable because brain maps are dynamic and always changing. “He thinks one reason people get phantom pain is that when a limb is cut off, its map not only shrinks but gets disorganized and stops working properly.” (p. 183)

Other sensations experienced by amputees include the memory of the explosion at the time of injury or pleasant sensations from other body parts or even “frozen” body parts (arms in slings at the time of injury).

Ramachandran then asked himself if these phantom sensations could be “unlearned.” His idea was to fight one illusion with another. By using an open box separated by a mirror an amputee was able to “amputate” the phantom limb. After looking at the mirror image of the phantom limb during 10 minutes a day for 4 weeks, the phantom limb disappeared.

This “body image” extends to other areas. Anorexics imagine they are fat when, in fact, they are near starvation. Others imagine something about their bodies to be wrong. Instead of plastic surgery, they need “’neuroplastic surgery’ to change their body image.” (p. 188) Contrary to conventional wisdom “Rama” believes that pain and body image are created by the brain and projected onto the body. Mothers soothing children and the placebo affect may very well turn down the brain’s pain production. “Ramachandran and Eric Altschuler have shown that the mirror box is effective on other nonphantom problems, such as the paralyzed legs of stroke patients. Mirror therapy differs from Taub’s in that it fools the patient’s brain into thinking he is moving the affected limb, and so it begins to stimulate that limb’s motor program.”(p. 195)

Remarkably, the work of neurologists has opened up more understanding of the WONDER of God’s creation, the brain. We have so much more to learn. Do you agree that pain is the dark side of plasticity?

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Redesigning the Brain Chapter 3 – Part 1 – The Brain That Changes Itself by Norman Doidge

In this chapter, Doidge introduces Michael Merzenich to us. His work has produced a cochlear implant for deaf individuals. For others with learning disabilities, he and his team have produced Fast ForWord, a software program. Fast ForWord disguises itself as a children’s game. With as little as 30-60 hours of treatment, big changes have been made. Children with autism have, unexpectedly also been helped.

“Merzenich claims that when learning occurs in a way consistent with the laws that govern brain plasticity, the mental ‘machinery’ of the brain can be improved so that we learn and perceive with greater precision, speed, and retention” p. 47

“The cerebral cortex,” he says of the thin outer layer of the brain, “is actually selectively its processing capabilities to fit each task at hand.” It doesn’t simply learn; it is always “learning how to learn” The brain  Merzenich describes is not an inanimate vessel that we fill; rather it is more like a living creature with an appetite, one that can grow and change itself with proper nourishment and exercise.” P. 48

In the 1930s neuroscientists were “localizationists” identifying the frontal cortex as the area for the brain’s motor systems (output), “which initiates and coordinates the movement of our muscles.” P. 28 They also identified three lobes behind the frontal cortex as the parts that process sensory input. These three lobes are temporal, parietal and occipital – receptors for the eyes, ears, touch receptors etc. p. 28 Dr. Wilder Penfield of the Montreal Neurological Institute began mapping the mind in the 1930s.  “One of the greatest discoveries Penfield made was that sensory and motor brain maps, like geographical maps, are topographical, meaning that areas adjacent to each other on the body’s surface are generally adjacent to each other on the brain maps.” P. 49

Since “scientists believed that the brain couldn’t change, they assumed, and taught that the maps were fixed, immutable, and universal – the same for each of us – though Penfield himself never made either claim.” P 49

Years later, Merzenich discovered that brains could change and that the brain maps were not fixed. He was able to use much finer instruments than had using microelectrodes during his graduate studies at John Hopkins. Merzenich and his colleagues laboriously mapped extensively parts of the brain during surgeries – placing microelectrodes are a part of a monkey’s brain and then touching different parts of the body. P. 51

In the 1960s two other scientists were micromapping the visual cortex. David Hubel and Tortsen Wiesel also at John Hopkins were learning how vision is processed using kittens. They learned that newborn kittens need to receive specific visual stimulation from the third to eighth week of life in order to develop normally. In the experiment one eye was sewn shut during the ‘critical period’ That eye was blind for life, but the part of the brain responsible for that eye had already begun to redesign itself for another use. These men received the Nobel Prize for their work. They demonstrated neuroplasticity in the ‘critical period” but remained localizationists, believing that the adult brain was hard wired.

This discovery of a critical period was reinforced with the work of other scientists. Different neural functions had their own critical period. “Language development, for instance, has a critical period that begins in infancy and ends between eight years and puberty. After this critical period closes, a person’s ability to learn a second language without an accent is limited. In fact, second languages learned after the critical period are not processed in the same part of the brain as is the native tongue.” P. 52

Etiologist, Konrad Lorenz learned that goslings could ‘imprint” or bond with a human if exposed to a human during their critical period of fifteen hours and three days.  P. 52

These discoveries caused doctors to do surgeries during that critical period to take advantage of this time frame., However, “Merzeninch’s first glimpse of adult plasticity was accidental.” After receiving his doctorate he and neurosurgeons Ron Paul and Herbert Goodman “decided to observe what happens in the brain when one of the peripheral nerves in the hand is cut and then starts to regenerate.” P. 53
Nervous System has two parts:
1) Central nervous system (the brain and spinal cord) – command and control center (thought to lack plasticity)
2) Peripheral nervous system  – brings messages to the spinal cord and brain and carries messages from the central nervous to the muscles and glands. (known to have plasticity – that is it could regenerate or heal itself).
Neurons have three parts:
1) Dendrites – treelike branches that receive input from other neurons.
2) Cell body – dendrites lead to the cell body – sustains life; contains DNA
3) Axon – living cable of varying lengths – carry electrical to neighboring neurons – very high speeds.  P. 53
Neurons receive two types of signals:
1) excitatory signals – when received the neuron will send its own signal
2) inhibitory signals – when received the neuron will be less likely to send off a signal p. 53-54
These neurons are separated by a microscopic space called a synapse.

In their experiment they cut the nerves on the hands of several adolescent monkeys. Then they sewed them together, but not closely enough to rejoin in the same place. They expected to see a chaotic brain map after seven months. To their surprise Merzenich said, “What we saw was absolutely astounding. I couldn’t understand it.” “It was topographically arranged as though the brain had unshuffled the signals from the crossed nerves.” P. 55 Merzenich realized that he and all scientist had it all wrong. The brain could normalize structure in response to abnormal input. Neuroplasticity beyond the ‘critical period’ had to explain this.

Merzenich scoured the library to find other evidence that contradicted localization:
1) 1912 – Graham Brown & Charles Sherington – “stimulating one point in the motor cortex might cause an animal to bend its leg at one time and straighten it at another” p. 55
2) 1923 – Karl Lashley – also found the same stimulus could produced a different movement.
He wrote a paper, but it was rejected. He was working in someone else’s lab.

Merzenich became a professor of the University of California of San Francisco in 1971. As a professor in the department of otolaryngology and physiology, he began some experiments under the guise of acceptable research. He was mapping the auditory cortex of different animals. This work contributed to invent and perfect the cochlear implant. Unlike a hearing aid, which amplifies sound in someone who is hard of hearing, the cochlear implant replaces the damaged cochlea in a deaf person. While the artificial cochlea is much simpler than the original, the fact that the brain could modify itself to the artificial one, is another indication that the brain at any age is plastic.

Later, Merzenich and Joh Vass of Vanderbilt University in Nashville cut the median nerve in the hand of adult monkeys. Two months later, the micromapping demonstrated that the radial and ulnar muscles had taken over much of the unused part of the brain previously used by the median nerve. The wrote up their results and used the word “plasticity.” P. 58-59

These experiments help us understand the competitive nature of plasticity. If you don’t use it in the original way, you lose it and some other function takes it over.

Merzenich’s work has much more to teach us so we will continue with this next time.

While many of these men were not Christians, we as Christians can see that we, indeed, “are fearfully and wonderfully made.” Psalm 139

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The Brain That Changes Itself – Chapter 1 – A Woman Perpetually Falling…

The Brain That Changes Itself by Norman Doidge, M.D.
Chapter 1: A Woman Perpetually Falling…Rescued by the Man Who Discovered the Plasticity of Our Senses

Doidge begins by telling of a lady (Cheryl Schiltz) who five years earlier (1997) suffered from a postoperative infection that was treated with the antibiotic, “gentamicin”. One of its side effects is loss of vestibular function. The doctor said that it would be permanent. Cheryl felt like she was continually falling.

We keep our balance due to the delicate vestibular system, which consists of three semicircular canals in the inner ear. One maintains balance with movement vertically, one horizontally and finally one forward and backward. There are tiny hairs in a fluid inside the canals. As we move these hairs move within the fluid. The brain interprets the information and as we move, we still see straight.  Some think of this vestibular apparatus as one of our senses.

Paul Bach y Rita and his neuroplasticity team had developed a device that, they hoped, would allow her vestibular system to be restored. After some very short trials, she used the device for 20 minutes. In addition to those 20 minutes, she experienced 3 hours and 20 minutes of residual effect. That was an amazing result for Cheryl and the research team, however, experiencing lack of balance again was very hard for her.  Over the next year, she used the device increasingly longer and now does not consider herself a “Wobbler” any longer.

Earlier, in 1969, Bach y Rita wrote an article for Nature, Europe’s premier science journal. On this occasion, he and his team had developed a device (tactile-vision) that allowed congenitally blind individuals to read, make out faces and shadow, and distinguish whether objects were closer or farther away. There were six subjects who were able to experience sight to some degree. While this device is long forgotten, it was one of the first demonstrations of using one sense to replace another.

This and other demonstrations would challenge the idea of earlier scientists that the brain was a machine. Also, challenged was the idea of localization — that is specific brain function was localized in one area only. Rejecting this idea, Bach y Rita set out to prove the mainstream idea as wrong.
Paul Bach y Rita has studied, researched and worked in a number of fields, following his quest wherever it took him. He says, “We see with our brains, not with our eyes. … our eyes merely sense changes in light energy, it is our brains that perceive and hence see.” P. 15      Because a blind man’s cane can help him “see”, Bach y Rita, believed that skin and touch receptors can substitute for a retina.

While in Germany in the early 1960s Bach y Rita began to doubt the concept of localization.  His research demonstrated that the idea of ‘one function, one location’ was flawed. P.  His tactile-vision machine further demonstrates that the brain, not a machine is the “miracle.”  Indeed, we can say with King David in Psalm 139, “…we are fearfully and wonderfully made.”

In 1959, Paul’s brother George had been told that their father had suffered a severe stroke and would not regain mobility and speech. After trying rehabilitation programs, he set out to rehabilitate his father. Since he couldn’t walk, he decided he would begin where babies begin – crawling. He first taught his father to crawl.  After a year of hard work, Pedro Bach y Rita was able to return to teaching at a University in New York. Thus, Paul understood that the brain could relearn.

By 2002, 33 years after Bach y Rita had written about his tactile-vision machine, scientists are using a smaller, modern version train the brain.  With modern technology they can indeed see that the tactile images are being processed in their brain’s visual cortex.  A modern neuroscientist, Mriganka, has surgically rewired the brain of a young ferret – using hearing and vision. P. 25  It is fascinating to read of the research that is being done… the discovery is that “...we are fearfully and wonderfully made.”

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