26 Aug Exercise, Movement, and The Brain (Yoga in Hounslow)
“Embodied cognition, the idea that the mind is not only connected to the body but that the body influences the mind, is one of the more counter-intuitive ideas in cognitive science.” writes Samuel McNerney for the Scientific American.
In sharp contrast is dualism, a theory of mind famously put forth by Rene Descartes in the 17th century when he claimed that “there is a great difference between mind and body, inasmuch as body is by nature always divisible, and the mind is entirely indivisible… the mind or soul of man is entirely different from the body.” In the proceeding centuries, the notion of the disembodied mind flourished. From it, western thought developed two basic ideas: reason is disembodied because the mind is disembodied and reason is transcendent and universal. However, as George Lakoff and Rafeal Núñez explain:
Cognitive science calls this entire philosophical worldview into serious question on empirical grounds… [the mind] arises from the nature of our brains, bodies, and bodily experiences. This is not just the innocuous and obvious claim that we need a body to reason; rather, it is the striking claim that the very structure of reason itself comes from the details of our embodiment… Thus, to understand reason we must understand the details of our visual system, our motor system, and the general mechanism of neural binding.
“Until as recently as 1995, researchers believed that the health benefits of exercise were limited to “the body” as opposed to “the brain.” writes Kimerer L LaMothe Ph.D for Psychology Today.
Now, however, the field has shifted. Not only is it clear that exercise primes brain cells with work-enabling oxygen, it is also evident that exercise actually catalyzes the growth of new brain cells (called neurogenesis) as well as the production of factors that aid in the creation of new synapses (called synaptic plasticity).
What is going on?
First a word about brains. In common parlance (thanks to Donald Hebb’s 1949 coinage), brain cells that “fire together wire together,” thereby creating new “synapses” or connections between one neuron and another.
In the moment of “firing,” an electrical impulse runs along the axon or branch of a brain cell to its tip. There it morphs into a neurotransmitter that leaps across the gap between one neuron’s axon and another’s receiving dendrite. These synapses represent something learned that may be remembered.
In this “wiring,” then, the neuron branches don’t touch. They don’t “wire” in the sense of fusing. What connects the neurons is a trace of a movement made—a trace that exists as an “affinity” between neurons, a potential for an impulse from one cell to jump to the other again in the future.
In other words, anything humans learn exists as what I call a kinetic image. It does not exist as a physical structure, it “exists” only in the movement it enables, regardless of whether that movement results in a thought, an emotion, or an action.
From the perspective of bodily becoming, the brain is movement. It exists as a template for movement potentials between neurons. Each neuron is a capacity for sensing and responding to a nudge from another neuron. That is what it is.
Rather than fire and wire, it might be more accurate to say that the neurons pop and neurotransmitters hop.
What effect does exercise have on this kinetic process that underlies all of our learning and remembering, our highest abstractions and most concrete sensory awareness?
New findings and new qualifications on older findings appear every week. For example, scientists have found that exercise increases glutamate, a neurotransmitter responsible in 80% of brain signaling for stirring up the activity that enables the signaling leap.
Exercise also appears to increase the release of growth factors—especially BDNF (brain-derived neurotrophic factor)—that works by thickening axons and dendrites and spurring neurons to sprout new ones. In other words, the BDNF works by boosting the potential of neurons to pop and hop—not by building an actual “circuit” or “net.”
Exercise works within cells throughout a bodily self as well to produce proteins that travel into the brain to support the activity of both neurotransmitters and growth factors.
Further, a study just published on November 19 suggests that exercise boosts cell production of an enzyme (SIRT3) located within the mitochondria that protects the mitochondria’s all-important energy production from the kinds of stresses caused by neurotoxins and other factors.
In these ways, then, exercise creates conditions that enable brain cells to learn—where that learning, from the perspective of bodily becoming, is a rhythm of creating and becoming patterns of movement that find expression in thoughts, feelings, and ideas. Exercise serves as an engine, outlet, and enabling condition for the rhythms of bodily becoming.
Often these findings are summed up using the metaphor of “plasticity,” affirming that exercise spurs synaptic plasticity. This metaphor implies that the brain is a substance that is malleable, changing shape in response to external forces. However, once we adopt a perspective of bodily becoming the metaphor of plasticity falls short. Our brains are not passively being shaped; they are actively participating in the shaping. Our neurons are themselves reaching, grabbing, triggering, tossing, and in so doing, creating the very organism whose ongoing health they exist to serve—as the condition of their own survival!
It might be more helpful to think of the brain as an ongoing, reflexive rhythm of kinetic image creation.
Why, then, does exercise have such a profound effect on a human brain? The perspective of bodily becoming suggests a reason. Bodily movement is a cue for a brain to wake up. Bodily movement signals to the brain that there are decisions to make; opportunities to take; dangers to avoid, and pleasures to pursue. Bodily movement signals to the brain that it is time to come fully on line and do the job it exists to do: guiding conscious participation in the rhythms of bodily becoming.
What kind of bodily movement is best for boosting brain action? When asked the question, John Ratey, Associate Professor at Harvard Medical School points to activities that are aerobic and involve learning movement patterns. “The more complex the movements, the more complex the synaptic connections. And even though these circuits are created through movement, they can be recruited by other areas and used for thinking… The prefrontal cortex will co-opt the mental power of the physical skills and apply it to other situations” (56).
His analysis points to dance, and the perspective of bodily becoming illuminates the significance of doing so. Dance is not simply exercise. It is not simply bodily movement. Dance is the kind of exercise that requires the brain to do what it does when it is involved in any activity at all. It does not simply oxygenate the brain and enable the creation of connections; it challenges neurons to make new connections. It does not just spur the grown of new and better brain cells, it puts them to use, creating patterns of sensation and response that form the basis of all of our patterns of attention and action. Dancing exercises the self-creating rhythms that are who we are as brain cells, full bodily movements, and at every scale in between.
The practice of any dance form can do something else as well: it can serve to cultivate a sensory awareness of oneself as movement. It can encourage the creation of neural affinities that express the patterns of attention to bodily movement that the action of learning those movements requires. It thus can serve to help a bodily self learn to move in ways that unfold its potential to do so.
Exercise enhances the ability of a brain to make new connections, and dancing requires it. Dancing we create ourselves.
SOURCES:
https://www.psychologytoday.com/us/blog/what-body-knows/201511/exercise-movement-and-the-brain
No Comments