Part 2 – On the Edge: Introducing Neuroplasticity
By Dr. Dana Leigh Lyons, DOM, AP
This is Part 2 in an Alchemist’s Notebook blog series exploring places of resonance, merger and synergy between neuroplasticity and Taoist-inspired Chinese Medicine practice. For an introduction and overview, see Part 1 – Parallels & Possibilities.
As we underscored in that post, everything—and every “self”—is always changing. This change takes place in relationship and unfolds as process.
The remainder of the series will unfold around those three focal points: Change, Relationship and Process.
Today, we begin with the first installment on Change.
It will serve as an opening to the still-emerging neuroscience paradigm, highlighting new discoveries about the brain’s flexible form and function and introducing the “embodied” mind.
Often, in thinking and learning about the brain, a particular myth prevails. This myth is based on two core premises.
The first is the notion of a hardwired brain—the idea that after a certain critical window of childhood development, our brains and patterns are largely fixed (and progressively deteriorate with age).
The second is the notion of a localized brain map—meaning a clearly defined, unchanging, universal layout of which part of the brain does what.
But even as this myth persists, modern neuroscience has proven it wrong.
Over the past decade, researchers at the leading edge of brain science have amassed extensive evidence of a profoundly plastic brain and a continually shifting mind.
These pioneers of a new, more nuanced neuroscience storyline have shown first, that the brain’s “maps” of neuronal connections are responsive, flexible and dynamic.
Second, these maps are open to—and indeed, destined for—modification from birth until death.
Their work is infused with promise and possibility, demonstrating the potential of the brain—at any age—to rewire itself, make new connections, change its patterns, and develop or heighten sensory, motor and cognitive capacities.
They have also unmasked the pitfalls of a plastic brain, probing its paradoxical traps and the implications of unwanted mind-body changes or patterning, as seen in cases of addiction, pain, and all manner of psycho-emotional and physical disease.
Increasingly, this emergent, evidence-based paradigm is finding its way into mainstream biomedicine and even popular culture, assisted by a proliferation of articles and books chronicling the work of leading “neuroplasticians” and drawing connections between their discoveries and relatively widespread practices and healing modalities (e.g., physical and mental exercise, meditation, “talk therapy,” Chinese Medicine) (1).
While this new paradigm has yet to trump the story of a static, segmented brain (at least in mainstream metaphor), it is making rapid headway.
Leveraging increasingly advanced technologies to reveal the inner workings of our brains in increasingly exacting detail, neuroplasticians are undermining last century’s myths and shifting understandings of ourselves.
As notions of neuroplasticity coalesced, emerging from results of rigorous studies and clinical observations, the 20th-century dogma of a “localized” brain began to loosen.
According to this dogma, the brain is the simplified sort typical of anatomy and physiology textbooks: each part is distinct and each location is the site of a specific, standardized function.
Situated within a “one location, one function” framework, the structures, systems and specialized areas of the brain are relegated clearly defined borders and clearly assigned roles.
Within this arrangement, distinct processing areas are mapped onto various lobes. As typically localized (i.e., as mapped in the average person), the frontal lobes comprise the core of the motor system, which initiates and coordinates muscle movements, while the temporal, parietal and occipital lobes comprise the core of the sensory system, which processes signals from sense receptors.
As early as the 1930s, efforts to bring these motor and sensory maps into focus revealed that they are generally topographical, meaning that sites next to each other on the body are roughly adjacent on brain maps.
They likewise demonstrated that cognitive and emotional processes are also mapped in the brain. Over the second half of the 20th century, researchers used increasingly sophisticated techniques to render these brain maps in greater and greater detail. They did not, however, prove that such maps are universal or fixed.
Within this localized layout, the related theory of “lateralization” emerged, assigning each hemisphere of the brain a particular realm of activity and influence.
The left hemisphere thus became known as the verbal arena, responsible for symbolic processes such as language and mathematical calculations. The right became known as the nonverbal arena, responsible for artistic, imaginative and visual-spatial activities.
Like sensory and motor maps, this lateralized layout was generally assumed—but never proven—to be predetermined, universal and unchanging.
The neuroplasticity paradigm does not refute these typical patterns of localization and lateralization. But, recognizing them as simplifications and generalizations, it offers a more nuanced account.
This evidence-based, revised version recognizes the brain as an interactive, responsive organ with highly malleable, interdependent parts.
Given the nature of nerve cells, which are constantly making and breaking connections, such qualities are hardly surprising.
At base, the “synaptic plasticity” of our neurons ensures that “modules operate not as precisely defined, separate units, but as continuous, related elements within the cortex” (2).
Michael Merzenich, a leading neuroplasticity researcher whose brain training programs and devices have helped hundreds of thousands of people with cognitive difficulties, pioneered this updated understanding.
He discovered that brain maps “are neither immutable within a single brain nor universal but vary in their borders and size from person to person” (Doidge 49).
Beginning in the 1960s and 1970s, he used techniques such as brain “micromapping” with tiny electrodes to prove “the existence of plasticity beyond a doubt,” convincing even skeptical mainstream neuroscientists (Doidge 57).
Building on this early work and his own research, Jordan Grafman, chief of the Cognitive Neurosciences Section at the U.S. National Institute of Neurological Disorders and Stroke, integrated plasticity into “a nondoctrinaire version of localization” (Doidge 275).
He concedes that the brain is partitioned into different areas that, during development, assume primary responsibility for different brain functions.
In complex activities, however, various areas interact, and neurons in all of them must be co-activated (so when we read, for instance, we can see, hear and understand words simultaneously).
While each aspect of the brain tends to take charge of certain functions, this is not fixed or absolute.
Neurons in the centre of the brain area responsible for a specific activity are “most committed to the task,” while those along that area’s borders are “far less committed” (Doidge 275).
Neighboring brain areas “compete with each other to recruit these border neurons,” leading to natural variations in the layout of neural terrain (Doidge 275).
Even when typical tendencies hold true, life experiences and border-zone competition lead to variation in the exact location of functional areas. The result is that the brain’s compartments, or modules, of neural networks are at once “universal and individual” (3).
Extreme manifestations of plastic localization appear in cases where brain areas are severely impaired or absent.
Grafman’s research subject Michele Mack, for example, was born without a right hemisphere yet tested normal at birth. Even now, a neurologist would likely need a brain scan to know one hemisphere is missing because mental functions typically performed in the right hemisphere migrated to the left side of her brain.
This radical variation on the norm was possible because the two hemispheres are initially very similar and only specialize with development. In still forming or very young brains, “structure is not inextricably tied to function,” and one hemisphere can assume jobs that normally go to the other (4).
This illustrates that “neuroplasticity is no minor phenomenon operating at the margins” but rather, allows for “massive brain reorganization” (Doidge 259).
Even among scientists who once doubted adult neuroplasticity, the fluidity of a child’s brain has long been acknowledged.
By the mid-1980s, surgical removal of a complete cerebral hemisphere was the treatment of choice for certain children with uncontrollable, potentially fatal seizures. Performed before a child is four years old, this operation can result in remarkable recoveries. Even with removal of the left hemisphere containing the brain’s language areas, a child can still learn to talk, read and write. Typically, the worst-case outcome is impaired peripheral vision and fine motor skills on the side of the body opposite the surgery (Begley 76)
Whether the result of surgery, injury or congenital abnormality, this sort of brain reorganization is not merely a case of functions shifting from one spot to the next. It also requires plasticity in how the parts and whole of the brain operate and interact.
In the example of a person born with one hemisphere or a child who has one removed, the remaining hemisphere must be extra-efficient in order to handle its double load. Likewise, the usual left-right relationship is absent.
Normally, the hemispheres engage in continuous communication: “Each not only informs the other of its own activities but also corrects its mate, at times restraining it and balancing the other’s eccentricities” (Doidge 280).
Rezoning Brain Space
The neuroplasticity literature abounds with cases illustrating that the brain’s layout is plastic not only in the unborn and children, but adults as well.
Sharon Begley chronicles many such cases in her book Train Your Mind, Change Your Brain: How a New Science Reveals Our Extraordinary Potential to Transform Ourselves.
Begley recounts discoveries of leading neuroscientists whose work with deaf and blind subjects “showed conclusively that when the brain is deprived of one sense, the cortex undergoes radical reorganization” (109).
Scientist Helen Neville, for instance, demonstrated that in the brains of people deaf since birth or early childhood, the auditory cortex receives signals from retinas and processes visual information.
Her work produced “some of the most dramatic evidence that the functions of the brain’s primary structures, even those supposedly so hardwired they practically have ‘visual cortex’ or ‘auditory cortex’ embossed on them, remake themselves in response to experience” (Begley 81).
In another example, scientists at Mark Hallett’s lab at the U.S. National Institutes of Health conducted various investigations examining the brains of blind subjects who read Braille. Using positron-emission tomography (PET) and functional magnetic resonance imaging (fMRI), Norihiro Sadato showed that Braille readers who were blind from birth processed tactile information in their visual cortex. He found that while the capacity to rezone in this way diminishes greatly if subjects become blind after adolescence, it does not disappear entirely.
Colleague Leonard Cohen showed that Sadato’s finding was causal rather than correlational; temporarily turning off the visual cortex of Braille readers left them unable to make sense of tactile Braille reading.
The scientists concluded that this “cross-modal plasticity” might be partly responsible for high levels of tactile perception among the blind. By leveraging the somatosensory cortex and visual cortex to process touch, they manifest heightened sensitivity. (Begley 94)
Such research continued into the new millennium, when another series of studies went further, showing that a sensory cortex (such as the visual or auditory cortex) could process even non-sensory input.
In 2003, for example, researchers Amir Amedi and Ehud Zohary found that the visual cortex of blind subjects was activated when they recalled spoken words or generated verbs. Amedi and Noa Raz also showed that blind subjects surpassed sighted ones in verbal recall capacity, indicating that their atypical visual cortex activity was functional.
In other words, “the brain is not going to let a little thing such as the lack of the expected visual signals keep the visual cortex…from being gainfully employed” (Begley 102).
Rather than sit idle, brain space not receiving sensory input can assume higher-level, cognitive responsibilities, undermining the myth of a fixed “functional hierarchy” among processing areas.
This fluidity of form and function is not limited to sensory and motor cortices. While such areas are particularly plastic on account of their numerous neurons and connections, plasticity is characteristic of all brain tissue.
This includes the hypothalamus, for instance, which regulates the body’s internal environment and instinctual responses to the outside world, as well as the amygdala, which acts as the body’s alert system and processes our most basic emotions. It likewise includes the hippocampus, which sorts incoming information, turning some of it into long-term memories.
Indeed, plasticity even encompasses brain areas that regulate breathing and process pain.
And Merzenich, the aforementioned neuroplasticity pioneer, has demonstrated that complex arrangements of neural connections, such as those representing human relationships, reflect the “same plastic principles as simpler maps” (Doidge 97).
The examples above are thus representative rather than comprehensive, offering but a glimpse of neuroscience research and clinical practice.
Grafman, in his work alone, has identified at least four types of neuroplasticity:
Mirror region takeover, in which one brain area takes over for its dysfunctional “mirror region” in the opposite hemisphere;
Map expansion, in which a brain area grows its territory through border-zone competition;
Sensory reassignment, in which one cortex receives signals from another sense in the absence of expected input; and
Compensatory masquerade, in which the brain compensates for impairment by utilizing alternative pathways.
Together, these various types of plasticity, documented in the research, demonstrate that the brain’s layout may reflect typical tendencies but is far from universal or fixed.
This plastic brain is not an isolated entity, separate from and reigning supreme over the rest of our body.
Rather, it extends outward, influencing and being influenced by the “energy and information flowing” through our entire being (5).
Such extension, possible through manifestations of mind, is not “merely” the non-substantive stuff of thoughts, feelings and instincts. It has a very substantive, very physical presence.
As more than 25 years of studies have shown, mind-body dualism simply does not exist. The brain, through the branching influence of the mind, is in fact embodied.
Neuroscientist and psychopharmacologist Candance Pert, through pioneering research on neuropeptide receptors and the immune system, was at the forefront of this discovery. She explains the underlying biochemistry in her book Molecules of Emotion: The Science Behind Mind-Body Medicine (6).
Neuropeptides—the focus of Pert’s book—offer one evidence-based example of the inseparable body-mind.
Produced primarily in the brain, these biochemicals (nerve proteins) circulate throughout the body, passing chemical messages to cell receptor sites and thereby regulating life processes at the cellular level.
Pert describes this information exchange as one of resonance. When the “voices” of a neuropeptide and a receptor hit the same note, they bind, setting change in motion.
And, because neuropeptides are emotion specific, this relationship is not limited to physiological call and response. High concentrations of neuropeptides are found in the brain’s limbic system, our so-called hub of emotion and instinct (serotonin, for instance, a neuropeptide involved in mood, is highly concentrated in the hypothalamus).
Consequently, emotions can influence physiological processes that unfold as neuropeptides, moving from the brain, bind to receptor sites throughout the body.
Pert thus dubs these biochemicals “molecules of emotion.”
Crucially, Pert does not replace one hierarchal arrangement with another or proclaim “the power of the mind over the body.” Rather, she asserts: “Mind doesn’t dominate body, it becomes body—body and mind are one” (Pert 187).
As communication and information flow through the organism as whole, “the body is the actual outward manifestation, in physical space, of the mind” (Pert 187).
And, since neuropeptides and their receptors are present in every cell and system, Pert concludes: “the mind is in the body, in the same sense that the mind is in the brain” (Pert 188).
Emotions, as “cellular signals” in this network, are situated at “the nexus between matter and mind, going back and forth between the two and influencing both” (Pert 189).
Thus begins the revolutionary story at the frontiers of neuroscience, bringing our minds and ourselves into sharper focus—a “focus” that is in fact shifting, in-determinant, and all encompassing (or all embodying).
And yet, this story, at its essence, long predated neuroplasticians. It has simply acquired new details and new names.
Part 3 of the series will relate today’s “cutting-edge” concepts to Taoist perspectives on transformation within the context of an ever-changing body-mind-spirit.
Then, Part 4 will discuss the benefits of merging modern findings and ancient insights within clinical practice. Here, they offer a more complete way of framing problems and possibilities and another approach for influencing treatment outcomes.
1. Norman Doidge, in The Brain that Changes Itself: Stories of Personal Triumph from the Frontiers of Brain Science (Penguin Books, 2007), catalogs the work of neuroplasticity visionaries who challenged the dogma of a fixed, static brain and pioneered a new paradigm. He dubs these scientists “neuroplasticians.” Citations of Doidge here are from this seminal work.
2. Joe Dispenza, Evolve Your Brain: The Science of Changing Your Mind (Health Communications, 2007), 163.
3. Ibid, 162.
4. Sharon Begley, Train Your Mind, Change Your Brain: How a New Science Reveals Our Extraordinary Potential to Transform Ourselves (Ballantine Books, 2007), 76. Citations of Begley here are from this work.
5. Daniel J. Siegel, Mindsight: The New Science of Personal Transformation (Bantam Books, 2010), 55.
6. Candance Pert, Molecules of Emotion: The Science Behind Mind-Body Medicine (Touchtone, 1997). Citations of Pert here are from this work. Notably, Pert recognizes Chinese Medicine’s ancient awareness of body-mind unity (187).