HERE IS WHY NEUROPLASTIC HEALING WORKS - From the block-buster book "THE BRAIN'S WAY OF HEALING" by Norman Doidge, M.D. A book everyone should read; the modern science the Western world needs to vigorously promote and expound - Keith Hunt
The Stages of Neuroplastic Healing
How and Why It Works
The chapters you have just read focused on two very different kinds of healing. The work of Michael Moskowitz focused on specific neuronal functioning issues, and on using the fact that plasticity is competitive, to rewire the brain by weakening a pathological pain circuit through the use of the mind. John Peppers radical self-improvement involved using the mind to strengthen specific neuronal circuits in parts of his brain not normally involved in walking. But his exercise also helped improve the general cellular functions of his neurons and glia, by triggering neuronal and glial growth factors and the development of new cells, and by improving brain circulation.
In the chapters that follow, I will focus on the role of energy, in one form or another, to awaken and assist a brain that is not functioning well. In this chapter, I lay out my understanding of the stages of neuroplastic healing. These stages are to be seen as a flexible framework, not as a rigid scheme. But to understand them, it is first necessary to understand three general processes that frequently occur in the brain when it has problems.
The Pervasiveness of Learned Nonuse
Since I wrote The Brain That Changes Itself, three things have become apparent to me.
The first is that learned nonuse applies not only to stroke. As discussed in the previous chapter, people who have had a stroke go through a crisis—diaschisis—in which the brain, immediately after the injury, goes into shock for about six weeks and functions poorly. Edward Taub showed that when a stroke patient tries repeatedly, during this period, to move the paralyzed arm, and cannot, he "learns" it doesn't work and so starts using only his nonaffected limb. In the use-it-or-lose-it brain, the already-damaged circuitry for the paralyzed arm withers further. Taub proved that if the good arm was put in a cast or sling, so that it couldn't be used, then extremely intensive, incremental training of the paralyzed arm could often restore function, even decades later.
By 2007 Taub had shown that brain injuries caused by radiation treatments also lead to learned nonuse. He has since found that it can occur in a partial spinal cord injury, cerebral palsy, aphasia (loss of speech from a stroke), multiple sclerosis, traumatic brain injuries, and people who have had brain surgery for epilepsy, and that these conditions can respond to his therapy* I began to see that learned nonuse could occur in other brain problems, such as Parkinson's, and even, at times, it seemed, in some psychiatric problems. Indeed, in any situation where brain function is lost or on the wane, a person may be understandably tempted to find ways to work around the deficit—and thereby unintentionally exacerbate the loss of this circuitry. The widespread if not universal existence of learned non-use means that often we cannot judge the level of a person's deficit, or potential to recover, until we first try to train the individual vigorously.
* Taub's many published works show great success in using Constraint-Induced Therapy to help patients deal with lost movement from stroke, traumatic brain injury, and multiple sclerosis and should, to my mind, always be considered for movement-related problems caused by brain injury or disease, including Parkinson's disease (with which he has also had anecdotal success). Studies of modified forms of Constraint-Induced Therapy have proven them effective in helping stroke victims with aphasia to regain speech, and they probably can help some vision problems, such as amblyopia, where the circuitry for vision in one eye "turns off." See V. W. Mark et al., "Constraint-Induced Movement Therapy for the Lower Extremities in Multiple Sclerosis: Case Series with 4-Year Follow-up," Archives of Physical Medicine and Rehabilitation 94 (2013): 753-60.
I have come to suspect that learned nonuse is such a common phenomenon in the brain because "going dormant" is a common strategy when a cell, or a more complex organ or organism, finds itself in a situation in which its normal ways of adapting to the environment fail.*
The Noisy Brain and Brain Dysrhythmias
The second concept that is applicable to many different brain problems is that of the noisy brain" that has problems firing in rhythm. I was originally exposed to the idea of the noisy brain in the lab of Paul Bachy-Rita, where he was working with Cheryl Schiltz (discussed in Chapter 7). Schiltz's balance system was injured by a medication, and she could no longer determine where she was in space. She said that her mind felt very "noisy" The scientists believed her subjective sense of "noise" mirrored what was happening in her neuronal circuits: her neurons couldn't generate enough strong, sharp signals in the balance system to stand out against the background noise of all the other neuronal signals being fired in her brain. Noise is a term from engineering, to describe what happens in a system when that system cannot recognize
* The temporary shifting into dormant states is a strategy seen in different kinds of organisms. In the plant kingdom, seeds can go into a dormant state if the external environment becomes too hot or too cold for them to control their internal cellular environment, and can survive without water, sun, or nutrients for centuries. The great physiologist who coined the term and concept "homeostasis," Claude Bernard, pointed to many cases of "latent life," wherein animals oscillate between fully active living states and dormant ones. The dormant ones occur when the animal can no longer maintain "homeostasis"—that is, it can no longer control its internal environment, because external conditions are not.compatible with normal life. The wormlike tardigrade, which has a nervous system and muscles, can, in drought, completely dry up. and remain dormant in an inactive state for extended periods, only to come to life when exposed to moisture. Some of these animals have been kept inert for as long as twenty-seven years. In these protected states of "suspended animation," energy consumption drops radically, until the animal can be revived. The revival often requires an input from the outside. I have discussed these examples of biological dormancy as a possible template for learned nonuse with Taub. He thinks that learning is sufficient to explain what we observe and thinks it is an open question as to whether other factors might contribute. But I would add, it might be both learned and instinctual. There are a number of instinctual capacities that require some "priming" by the environment-—which involves learning—to be triggered. See C. Bernard, Lectures on the Phenomena of Life Common to Animals and Plants, trans. H. E. Hoff, R. Guillemin, and L. Guillemin (1878; reprinted Springfield, IL: Charles C. Thomas, 1974), pp. 1:49-50, 56.
normal signals because they are too weak compared with the background "noise." Hence the "noisy brain."
I would put it this way. In a brain injury, from whatever cause (toxins, stroke, infection, radiation therapy, blow to the head, degenerative disease), some neurons die and cease to give off signals. Others are damaged, but—and this is key—they don't necessarily "fall silent." Living brain tissue is, by nature, excitable. Even when a brain circuit is "off," it continues to fire some electrical signals, although at a different, often slower rate than when it is activated and "on." In this view, the brain is like the heart. At rest, it doesn't stop; rather, it shifts into a resting rate. When the heart's electrical system is damaged, it loses the ability to regulate its firing rate and gives off aberrant signals of various kinds: its natural pacemakers may run too slowly, or race at dangerous speeds, or lead to chaotic irregular beats called either arrhythmias or dysrhythmias.
In the brain, these irregular signals have an effect on all the networks they are connected to, "messing up" their functioning as well— unless the brain can shut down its damaged neurons. In many brain problems, we now know, neurons are firing at the wrong or unusual rates. This problem occurs in epilepsy, Alzheimer's, Parkinson's, many sleep problems, and brain injuries, among others: they create a noisy brain because so many of the signals are out of sync* Something similar is seen in the aging brain, in the brains of children with learning disorders, and in sensory problems when neurons can't fire sharp, clear signals.
When sick neurons render the healthy ones that receive their irregular signals ineffective, they may become dormant. A recent important study by Taub's group, using brain scans, has shown that when a stroke kills neurons in what is called the "infarct" area, other neurons, still living but far from the dead cells, can show signs of atrophy or wasting away.
* A number of neuroscientists, among them Rodolfo Llinas, Barry Sterman, and Paul E. Rapp, an expert in traumatic brain injury, have documented brain dysrhythmias in a variety of neurological and psychiatric disorders. Support for the idea that "sick" neurons fire improper signals comes from neurofeedback (see Appendix 3). Special EEGs show that in brain injuries, patients often have areas of the brain that fire inappropriate "slow wave" activity. When patients are trained, with neurofeedback, to make slow waves to fire at a more normal rate, their brain injury symptoms can often decrease.
The extent of this atrophy correlates with the patient's difficulties and how well he or she will do in Constraint-Induced Therapy. (Taub thinks, as do I, that this wasting away of neurons most likely occurs because these areas are not getting proper signals from sick neurons, according to the use-it-or-lose-it principle, or because they are exhibiting the poor brain health that predisposed the person to the stroke, or both.) Thus, when patients try to perform an activity that requires aU this circuitry they fail and, at this point, I believe, develop learned nonuse. Worse, not only do they lack access to skills they once had, they have trouble learning new ones because the noisy brain cannot make fine distinctions or differentiations.
In summary, though such patients cannot perform certain tasks, only some of the neurons that normally process those tasks are dead; others are alive but distressed and firing irregular, noisy signals, and others are merely dormant because they are getting bad signals. The approaches I describe in the chapters to come can often foster improved health in the sick, noise-generating neurons and use energy and neuroplastic approaches to retrain the surviving neurons to fire in sync and reawaken dormant abilities.
The Rapid Ongoing Formation of Neuronal Assemblies
The third major factor that allows neuroplastic healing derives from the uniqueness of neurons, compared with other cells. Neurons usually work in large groups, communicating electrically through widely distributed networks throughout the brain. These networks are constantly reforming themselves into new "neuronal assemblies," as the neuroscien-tists Susan Greenfield, Gerald Edelman, and others have emphasized. This appears to be especially true for conscious activities. Since no conscious mental act is entirely the same as another, in each mental act slightly different combinations of neurons communicate with one another. Thus, as a person goes through the day, her brain is forming, un-forming, and reforming new neuronal networks as part of its basic operating procedure. In this respect, the organic living brain is quite the opposite of an engineered machine with hardwired circuits that can perform only the limited number of actions that it has been designed to do. Machines generally perform an action the same way every time.
A neuron, or group of neurons, however, will be used for different purposes, at different times-—a sign of how flexible neuronal networks are. In 1923 the neuroscientist Karl Lashley exposed a monkey's motor cortex and stimulated it with an electrode in a particular place. He observed the resulting movement, then sewed the monkey back up. After some time he repeated the experiment, stimulating the monkey in that same spot, only to find that the resulting movement often changed. As Harvard's great historian of psychology of the time, Edwin G. Boring, put it, "One day's mapping would no longer be valid on the morrow."
Thus, when the brain has been damaged, it may, in some situations, be able to do the same task using different coalitions of neurons.
Scientists once imagined that memories, or skills, were processed in discrete, small locations in the brain. But Lashley showed that this was often not the case. His most famous experiments involved teaching an animal, such as a rat, to perform a complex activity to get a reward. Then he would damage brain tissue in the part of the cortex thought to process that skill. Surprisingly, the animal could still perform the activity, though it might take longer or be less precise. Why this result occurs is open to interpretation, but from Lashley's work, scientists learned that many skills involve much more widely distributed neural networks than had been believed. It also showed that these networks have a lot of redundancy, because parts can be removed, and still the animal can perform the task*
* It is possible to integrate the best of Lashley's findings with studies of brain locations, which I do in The Brain That Changes Itself, especially in Chapter 11. There is something to finding specific locations for certain mental activities in the brain, or "localizing them," but some forms of localizationism are "immature" and overly rigid, while more mature forms take into account brain plasticity. Just because the brain tends to process certain mental activities in certain areas doesn't mean it always must. Immature localizationism doesn't recognize this fact. As the reader can already appreciate, I frequently talk of certain brain areas as being "involved in" processing specific mental functions. What I mean by "involved in" is that these areas tend to participate in these mental functions and may even be necessary for those functions, but the circuit is usually much broader than the named area, involving many other brain areas, and for many functions the brain works more holistically than immature localizationism implies. Saying that "the hippocampus is involved in processing short-term memory" is more accurate than saying "short-term memory is processed in the hippocampus." The Brain That Changes Itself gives numerous examples of how, when large parts of the brain are damaged or absent, other brain areas can take over their mental functions. Taub's group has shown that there is very little correlation between where a stroke lesion, occurs, and its size, and how well patients do in Constraint-Induced Therapy, with the exception of a stroke in an area called the corona radiata. See L. V. Gauthier et al., "Improvement After Constraint-Induced Movement Therapy Is Independent of Infarct Location in Chronic Stroke Patients," Stroke 40, no. 7 (2009): 2468-72; V. W. Mark et al., "MRI Infarction Load and CI Therapy Outcomes for Chronic Post-Stroke Hemiparesis," Restorative Neurology andNeuroscience 26 (2008): 13-33.
It is important for laypeople to remember the following, perhaps shocking, point. It is well established that mental activity correlates with neuronal activity, and that as learning occurs, new connections are formed between neurons. But when neuroscientists sometimes say, using shorthand, that "our thoughts are in our neurons,5' they are radically overstating what the science has shown. To say that when thoughts occur, neurons fire and form links with one another is to describe two things happening at once. But neuroscientists really do not know where "in' the neurons thoughts are encoded. Nor do they know if they are "in" individual neurons (highly unlikely), or in the connections between the neurons, or distributed throughout the brain. This mystery of the mind remains unsolved.*
Lashley appears to have been the first neuro scientist to propose an interesting alternative: that learning and skills are encoded not "in" specific neurons, or even "in" the connections between neurons, but "in" the cumulative electrical wave patterns that are the result of all the neurons firing together. (This important hypothesis was taken up by the neurosurgeon and neuroscientist Karl Pribram, who developed a brilliant theory of how the brain encodes experience.)
Let us imagine that brain functions—such as thoughts, memories, perceptions, and skills—are encoded not in individual neurons but in the patterns that can be generated by different coalitions of neurons. (To use an analogy, the patterns are like a musical piece, and the neurons are the orchestral musicians that play the piece.) Loss of some individual neurons, from neuronal death or disease, would not necessarily lead to the loss of a mental function, as long as enough of the brain's neurons
* How neuroscientists overstate our knowledge about "where" mental activity is localized in the brain, and confuse the mind with the material brain, is described in neuroscientist Raymond Tallis's extremely thought-provoking book Aping Mankind: Neuromania, Darwinitis and the Misrepresentation of Humanity (Durham, UK: Acumen, 2011).
remained and were able to generate these patterns. (To continue the music analogy: if one member of the string section is sick, the show can still go on, if his replacement has access to the musical score.)
Much of what we consider to be our essence is not in our individual neurons, anyway, all of which are quite similar. So much of the specifics of "who we are" is related to our encoded experience, which is carried in the patterns of energy that our brain generates. The coded patterns of experience can often survive structural damage to the brain.*
The Stages of Healing
I have observed the following stages in neuroplastic healing. Often they occur in the order presented here, but that need not always be so; some patients need to go through only some of these stages to heal, while others must pass through all of them.
Correction of general cellular functions of the neurons andglia. This is the only stage that does not directly address "wiring issues"—that very specialized ability of neurons to connect to and communicate with each other—but instead focuses on the general health of the neurons, and the cell functions they have in common with other cells. In many brain problems, the brain becomes "miswired" because the neurons and the glia have been disturbed by an external source (such as an infection, a heavy metal toxin, a pesticide, a drug, or food sensitivity), or they have been undersupplied with resources, such as certain minerals. These
* The biological thinker Ludwig von Bertalanffy reminds us that the sharp separation between structure and function really best applies to machines, which can only be on or off and are made of inanimate matter. In organisms, it is better to think of processes. "The antithesis between structure and function ... is based upon a static conception of the organism. In a machine there is a fixed arrangement that can be set in motion but can also be at rest. In a similar way the pre-established structure of, say, the heart is distinguished from its function, namely, rhythmical contraction. Actually, this separation between a pre-established structure and processes occurring in this structure does not apply to the living organism.... [In organisms] what are called structures are slow processes of long duration, [while] functions are quick processes of short duration." Ludwig von Bertalanffy, Problems of Life: An Evaluation of Modern Biological Thought (London: Watts & Co., 1952), p. 134. In trying to understand how neuroplasticity facilitates healing, we can regard mental acts, such as thinking, as processes that are of short duration but can have an effect on processes of long duration, the so-called structure of the brain. While thought itself cannot resurrect dead tissue, it can stimulate any remaining healthy tissue to reorganize itself to take on the lost functions of the damaged tissue.
general problems are best corrected before beginning the stages that follow for the patient to get the most benefit.
This general cellular repair stage is especially relevant in treating autism and learning disorders, and in lowering dementia risk, for example. It also applies to common psychiatric disorders. I have seen patients with depression, bipolar disorder, and attention deficit disorder make major progress by eliminating toxins and certain foods, such as sugar and grains, that they were sensitive to.
Many of these interventions involve the glial cells, which make up a full 85 percent of all the cells in the brain. The brain has a barrier around it, called the blood-brain barrier, that protects it from invaders, and it has no lymphatic system—the system of vessels that is very important for the immune system and healing elsewhere in the body. Instead, small "microglial" cells protect the brain from invading organisms, and they are one of the unique ways that the brain protects and heals itself. The glia also support the neurons by getting rid of waste products produced by the brain.
The following four stages all make specific use of the neuroplastic capacities of the brain to alter the connections between the neurons and to change its "wiring."
Neurostimulation. In almost all the interventions in this book, some kind of energy-based neurostimulation of the brain cells is required. Light, sound, electricity, vibration, movement, and thought (which turns on certain networks) all provide neurostimulation. Neurostimulation helps to revive dormant circuits in the hurt brain and leads to a second phase in the healing process, an improved ability of the noisy brain to regulate and modulate itself once again and achieve homeostasis. Some forms of neurostimulation begin from an external source, but other forms are internal. Everyday thought, especially when used systematically, is a potent way to stimulate neurons.
When we think particular thoughts, certain networks in the brain are "turned on," while others are switched off. This process was the basis of Moskowitz's visualization cures of chronic pain (see Chapter 1). Once a relevant circuit is turned on by thought, it fires, and then the blood flows to that circuit (a process that can be seen on brain scans that monitor blood flow in the brain) to replenish its energy supply. I believe that Taub's Constraint-Induced Therapy, though a movement-based behavioral therapy involves great intentional effort and motor planning, so it too likely triggers some thought-based neurostimulation. (It also involves the final phase, neuro differentiation and learning) Pepper's conscious walking, to build up new circuits in his brain, is an example of internal neuro stimulation using thought. Neuro stimulation is effective in preparing the brain to build new circuits and in overcoming learned nonuse in existing circuits. Brain exercises, and many of the forms of mental practice described in The Brain That Changes Itself, are forms of internal neuroplastic neurostimulation.
Neuromodulation. Neuromodulation is another internal method by which the brain contributes to its own healing. It quickly restores the balance between excitation and inhibition in the neural networks and quiets the noisy brain. People with a variety of brain problems can t regulate sensation properly. They are often too sensitive to outside stimulation or, alternatively are insensitive to it. Neuromodulation restores the balance. As we shall see in Chapter 7, neurostimulation can trigger neuromodulation, improving brain self-regulation, generally.
One way neuromodulation works is by resetting the brain's overall level of arousal by acting on two subcortical brain systems.
The first such system is the reticular activating system (RAS), which is involved in regulating a person's level of consciousness and the overall level of arousal. The RAS is housed in the brain stem (an area of the brain between the spinal cord and the bottom of the brain) and extends up toward the highest parts of the cortex. It can "power up" the rest of the brain and regulate the sleep-wake cycle. I shall show in the following chapters how stimulation with light, electricity, sound, and vibration often causes patients with a brain problem (who are- usually exhausted and jittery from having a brain issue) to begin sleeping deeply, to wake up restored, and to develop a better sleep cycle. Resetting the RAS is essential to helping the brain restore its energy supplies, which it will call upon to heal further.
The second way neuromodulation works is by affecting the autonomic nervous system. Millions of years of evolution [OBVIOUSLY DOIDGE DOES NOT BELIEVE IN A CREATION BY GOD - Keith Hunt] have equipped human beings with "preset," automatic, involuntary nervous system reactions, to prepare them for nature's emergencies—as when predators suddenly attack and there is little time to think. These ready-made automatic reactions are built into the autonomic nervous system, called "autonomic" because it was thought to be largely automatic and not under voluntary control.
The autonomic nervous system has two well-known branches. The first is the sympathetic fight-or-flight reaction, which mobilizes a person for action and shunts blood to the heart and muscles so he or she can fight off a predator or a dangerous rival, or run away. Both fight and flight require a large discharge of energy and an increase in metabolism (to access the energy needed for immediate use). Designed for immediate survival, this system focuses all a person's activities on that purpose and often inhibits growth and healing processes. Many patients with brain problems, or learning problems, are often in a state of sympathetic fight-or-flight, feeling desperate, endangered, and hyper-anxious because they can't keep up with unfolding events. The problem is that a person in fight-or-flight can't heal or learn well in this state, which makes brain change harder.
The second branch is the parasympathetic system, which turns off the sympathetic system and puts a person into a calm state in which he or she can think and reflect. While the sympathetic system is often called the fight-or-flight system, the parasympathetic is sometimes called the rest-digest-repair system. When this system is turned on, it triggers a number of chemical reactions that promote growth, conserve energy, and increase sleep, all of which are necessary for healing. It also recharges the mitochondria, the power sources inside the Cells (which I will discuss at length in Chapter 4), reenergizing them. Finally, and of special importance, recent studies by Michael Hasselmo and his colleagues from Harvard show that turning off the sympathetic system appears to improve the signal-to-noise ratio in brain circuits. Thus turning on the parasympathetic system is probably another way to quiet the noisy brain. Many of the techniques in this book turn on the parasympathetic system, and turn off the sympathetic system, rapidly relaxing people and preparing them for growth. In Chapter 8, we shall learn that the parasympathetic system also turns on a "social engagement system," which allows us to connect to other human beings, and use them to soothe and support us, and help us to regulate our own nervous system.
Neurorelaxation. Once fight-or-flight is turned off, the brain can accumulate and store the energy that will be needed for the efforts of recovery. Subjectively the person relaxes, and often catches up on sleep. Many people with brain problems are exhausted, and poor sleepers. A recent discovery by Maiken Nedergaard from the University of Rochester showed that in sleep the glia open up special channels that allow waste products and toxic buildups (including the proteins that build up in dementia) to be discharged from the brain through the cerebral spinal fluid, which bathes much of the brain. This unique channel system is ten times more active in the sleeping brain than in the waking state. This helps explain why loss of sleep leads to a deterioration in brain function: too much sleep deprivation leads to a toxic brain. The neurorelaxation phase appears to correct this, and can last several weeks, in some cases.
Neurodifferentiation and learning. In this final phase, the brain is rested, and the noisy brain has been modulated and is much "quieter," because the circuits can regulate themselves. The patient is able to pay attention again and is ready for learning, which involves the brain doing what it does best: making fine distinctions, or "differentiating." Many brain exercises for learning disorders and those that are based on listening therapy, for instance, involve training a person to make increasingly subtle distinctions in sounds*
All these phases combined foster the optimal amount of neuroplas-tic change, but as we shall see, each of the following chapters will em-. phasize different states. Chapter 4 will focus on restoring general brain cell health, as will parts of Chapter 8 and Appendix 2, on Matrix Repat-terning. Chapter 6 will emphasize neurorelaxation. Chapter 7 will emphasize neurostimulation and neuromodulation to reset the brain. Chapter 5 will emphasize the final stage, differentiation. And Chapter 8, on sound, will show all the phases working.
* Sometimes skeptics argue that the discovery of neuroplasticity is nothing new, and that neuro-plastic healing is merely learning. Only this last phase involves normal learning, however, and the plastic effects of learning in the brain are not the same as the mental activity of learning.
While most people with a brain injury will have to go through each of these stages in their treatment, many of the problems in this book do not derive from brain injury; rather, they require that the patient build up circuitry that had never developed. Some, for instance, require only neurostimulation and neurodifferentiation to do this. And others will benefit from several different interventions.
An individual's progress is never, in this neuroplastic approach, dependent solely on the technique, or the disease or the problem alone. We don't treat diseases, we treat people. Because of genetics, and neuroplas-ticity itself, no two brains are alike, and no two brain problems—or injuries—are identical. A person with a generally healthy brain who has an injury can't be compared with a person with a similar injury who has had exposure to drugs, neurotoxins, a previous stroke, or serious heart problems. Location of harm matters: a bullet to the breathing center will kill instantly, before a person has time to "rewire"; damage to the attention centers might make it difficult to do brain exercises. Yet even attention can be neuroplastically trained, sometimes, as neuro scientist Ian Robertson has shown.
The next chapter describes an approach that triggered the first three stages for a patient who, because she was exceptionally resourceful, put together her own program to trigger the neuro differentiation and learning stage.
AGAIN LET ME SAY HIS FOLLOWING CHAPTERS JUST BLEW ME AWAY - HIS BOOK NEEDS TO BE A STANDARD TEX-BOOK FOR ALL ENTERING THE MEDICAL WORLD; A COMPULSORY READING. IN FACT ALL PEOPLE, ALL HIGH-SCHOOL STUDENTS, NEED TO READ THIS BOOK - Keith Hunt