08 Maps to the Mind + Emotions
When he was in his late seventies, my Dad began to experience considerable lethargy. He had trouble moving and sustained a couple of serious falls. He wrote less. I’d find his daily New York Times, a favorite read, unopened just inside his front door. He seemed a little down and withdrawn. Always a social person, he saw his friends more infrequently. We went to see a neurologist, who diagnosed Dad with a neurodegenerative disease called cerebellar ataxia. It was progressive, the doctor said; there was no treatment.
We immediately instituted a regimen of yoga five times per week. This consisted mostly of private lessons from me, which Dad vastly preferred to the weekly senior yoga classes where I dropped him off and where to his dismay, as the only male in a 50-person class, he was a huge hit.
The changes were immediate and striking: Dad’s gait improved. His mood got better. He began writing again. His social disposition returned. Because his illness was usually rapid and progressive, we visited his neurologist every few months. “I have to say,” the doctor remarked each time in surprise, “you’re not getting any worse.” My Dad would smile proudly and tell him it was the yoga. His doctor, lovely though he was, would make small sounds of disagreement.
But what was happening in Dad’s body and brain? What does proprioception look like beyond the level of muscle fibers and receptor cells? And why might we want to know about it?
The scientific part of last week’s column ended with the arrival of proprioception in the brain. This week, let’s take a closer look at what happens when it gets there.
Understanding the how your brain maps your body will give you ways to preserve and even expand this special sense and with it, a key node of your emotional and social health.
Proprioception in the Brain
Once proprioceptive information reaches the brain, wild things happen.
Your brain actually contains maps of your body—countless maps, in fact, cosseted in different areas. The primary part of the somatosensory (body-sensing) cortex, known as S1, contains multiple maps of your body. One of these, the homunculus, has a unique topography: Each landmark corresponds to a specific area such as your face, hands, tongue, feet, or genitals. Its scale derives not from the size of these parts, from but from the sensitivity of their nerves. The receptors in your hands, mouth, and face have more responsivity, so they occupy a larger section of the map than other areas.
Adjoining S1 is the primary motor area, which has a map of its own. Designed similarly but in a “messier” way, this map’s points correspond to the most important movements, and to the ones you make most often. Here in M1, your brain processes sensory input from the body and integrates it with the motor input necessary for making skilled movement s.
Your brain’s body maps have remarkable stability. In people who lose a limb, for example, the map still allots space for the limb. They may have phantom limb pain, intense discomfort where the missing limb would be. They may perceive detailed information about where the limb is located in space. They may also experience the sense that they can control its position, which is also an element of proprioception.
Our brains often use past proprioceptive input to predict future experiences with movement and space; they map our former bodies, not our current ones. This same mapping stability can also occur after a change in body size. Years ago, after a grueling duo of hip surgeries, the swelling around my hip increased the width of my lower body. Accustomed to needing less space, I often (painfully) banged that side into door frames while passing through.
At the same time, the brain’s body maps adapt in response to experience. When someone loses a hand, for example, that area of the body map is taken over by a neighboring part—in some cases, a cheek. (The hand and face, though distant from each other on the body’s outer surface, have more sensitivity and thus are neighbors in the brain’s sensory body map.) And in people born without upper limbs who use their toes for artistic and other pursuits, the toe portion of the brain’s body map gets reorganized for more intricate tasks.
This combination of stability and adaptability is essential: Too much change would prevent our brains from anticipating and completing basic movements. At the same time, our brain maps need to be responsive to the full spectrum of experiences that come with inhabiting a living body.
Your brain’s spatial and movement maps aren’t the only parts of the brain that contribute to proprioception. The secondary part of the body-sensing cortex, called S2, helps store and process the information from S1.
Although it remains grounded in the body’s cartography, S2 also builds on it. Together with a neighboring chunk of neural real estate, it acts as an integration zone. It synthesizes spatial body maps and proprioceptive input with other inner senses like touch, balance, temperature, and interoception. It folds in outer senses like vision and audition. And it enriches this sensory brew with high-level conceptual information related to self-recognition, self-location, self-awareness, and the image we have of the body as a whole. It then creates a cohesive experience of our bodily self in relationship with the environment around it.
This upgraded body-to-environment map includes other people’s bodies, too: Several human MRI studies report that S2 activates not just when subjects are being touched, but when they observe others being touched by objects.
The cerebellum, or “little brain,” is a thin sheet of tissue that sits just below the brain toward the back of the skull. The cerebellum helps process sensations from the muscles and tendons involved in posture, reflex, balance, coordination, and movement. It plays a role in motor learning, the trial-and-error process you use to master a new skill such as riding a bike or balancing on your forearms in yoga.
The cerebellum also contributes to mental functions like processing language and mood. It regulates your pleasure and reward response. It modulates emotional and social functioning.
The cerebellum has a number of maps of its own; some relate to visual-spatial capability, attention, and executive function, and movement. And new research reveals distinct representations for working memory, language, emotional processing, and social cognition.
This explained why cerebellar ataxia creates a challenge not just with walking and balance, but with energy, motivation, emotional regulation, and social connection.
But it also tells us that for all of us, a loss in our brain’s body maps doesn’t just impact us physically; it has motivational, emotional, and social effects too.
The Silent Loss in Our Movement Maps
Over time, it became clear that Dad’s brain maps had begun to “lose” certain movements. One Spring evening, we headed to his place to pick him up for a movie. Dad seemed fine on the way downstairs, and waved to my sister, whose car idled in the driveway. But he couldn’t step down off the small curb. I waited on the street, supporting his hands from beneath. He inched a Nike-clad toe toward the edge, only to draw it back again. He gritted his teeth and tried again; nothing. No amount of physical support or encouragement helped. Finally, my sister maneuvered the car close to the curb; I opened the front door. Clinging to the door frame, we swung Dad close enough that with me pushing, my sister could reach across, grab him by the belt, and pull him into the front seat.
I’d witnessed his brain give the command, but his body had been unable to execute it. I felt his fear and frustration as his ability to move and act defied him.
What does Dad’s loss of movement have to do with the rest of us?
In last week’s column, I mentioned proprioceptive loss in relation to sarcopenia, the decreased muscle mass, muscle strength, and performance that begins for almost all of us in mid-adulthood and gains velocity over time. Although people often characterize this is a muscle issue, it’s more like an erosion in communication between the body and the brain.
A big part of this erosion occurs in the brain’s body part and movement maps.
What’s more, proprioceptive loss and a “fading” of our brain’s body maps has a negative impact on emotional and social health. It may even be a drive of anxiety, depression, and our sense of meaning and belonging.
The fear and frustration he felt exists to some degree within all of us as we begin to “lose” our repertoire of movements.
How Our Loss May Be Our Gain
I’m not philosophically against the losses (or gains) that come in tandem with the process of aging. Loss is part of life. And strange as it may sound, knowing about this loss is good news.
Understanding both the stability and adaptability of the brain’s body maps over time allows us to take steps—literally—to keep these maps robust and even to expand them as we age. It helps us take note of the way strengthening these maps benefits emotional and social well-being. And we can use this as a therapeutic tool.
There’s a paradox here: Loss can be offset and even beautified when it lives alongside and in tandem with restoration. There’s something beautiful about the process of rehabilitation, the joy that can accompany the restoration of movement. This philosophy applies to proprioception, and to the brain’s maps of the body.
I’ve been through and written about the process of loss through surgery.
Today, I’d like to offer two ways of exploring and working therapeutically with our proprioceptive mapping: movement restoration and movement map expansion. These are not mutually exclusive; in fact, they often occur at the same time.
Movement Restoration
Restoration refers to restoring movements we had as a child and lost. This isn’t limited to sporty things, but to basic movements like crawling or climbing trees.
Perhaps the first step in working with movement loss is to notice it. We can watch gently for and bring mindful, nonjudgmental awareness to any movement loss that occurs. That’s easier said than done; the mind would rather look anywhere else. For example, I’ve noticed some movement loss this year while swimming in the pool. After a childhood of competitive swimming, racing turns have always come easily to me. And yet, there have been several sessions this winter when my racing turns are off and I wind up making the turn underwater, or sideways. Or I misjudge the distance I need to be from the wall, turn too early, and have to reach for the wall with my feet. Some of this is due to recent inner ear and vertigo challenges. Nonetheless, although the muscle memory is there, I can feel the body-to-brain disconnect that my Dad experienced. This gives me the agency to work on restoring that movement more fully.
Sometimes, novel movement can occur in the context of rehabilitative or pain treatment, or through working with a professional in a movement discipline such as Dynamic Neuromuscular Stabilization or Egoscue Method.
Movement Map Expansion
I speak frequently in Masterclasses about the value of novel movement. This is what some movement circles refer to as recovering movements (such as crawling, or sitting on the floor) that we’ve lost. This is offered in numerous circles today, such as MovNat or Parkour; some of these methods take place outside, in synergy with the natural world, which is a huge bonus. These days, there are numerous online videos available for free, which helps bring a much-needed equity to these disciplines.
You can also take up movement activities that you’ve never tried before. After 3+ years of pandemic and just as long immersed in research for the endless book-in-progress, I know that a new movement practice right now would be deeply nourishing for me, and it’s on my agenda.
So what gets in the way of movement restoration besides the busy pace of our lives?
The Social Context of Proprioception
Recognizing movement loss, the absence of something vital, can be challenging. It takes us to a deeply vulnerable place. (It may also provide a ground for meditating on impermanence.) It feels awkward and ungainly; our minds strain away from the recognition, to forget what they’ve noticed and immerse back into our “normal” movement routine.
There’s also the issue of momentum. Once we’ve built in certain kinds of movement and orientations to space, it’s easier to yield to the momentum and continue. We can set ourselves on autopilot, and simply yield to that gravitational pull.
Read my article Embracing Awkward in Yoga International.
And finally, there’s the social context of mastery. Taking up a new activity means that most of us won’t be “good” at it—at least, not right away. The forces of media, social media, and capitalism actively discourage living in that place of learning and not being able to demonstrate our mastery—which dominant culture equates with our inherent goodness and lovability. For yoga and movement people or fitness enthusiasts, this dynamic can be more pronounced.
Whether you move your body in solo practices, or with loved ones, or offer practices to others, knowing the inner barriers to restored, new, or awkward movements can be familiarize yourself with resistance. Building in these movements, or actions within movements, may not make you wildly popular as a teacher. And yet, you’ll be giving your community the gift of movement awareness, restoration, and expansion. You’ll be able to see the joy, agency, and belonging expressed in their bodies. Like parenting, this is the kind of “return” that far outlasts popularity.
There’s a huge bonus to doing this hard work:
Tolerating the awkwardness and vulnerability of new learning and movement expansion is a gift that keeps giving. What we do in our bodies changes our minds and brains. It generalizes to new learning in emotional and social contexts. It helps us become more vulnerable. Set better boundaries. Have difficult conversations around intimacy and reciprocity. And ultimately, it helps us expand our repertoire and tolerate discomfort in areas or social justice and equity. (Which, like movement loss, can register as the absence of something vital.)
As Dad taught me, loss of our movement repertoire makes us feel depressed and socially disengaged. The extraordinary value of movement restoration is that it doesn’t just expand the brain’s spatial and movement maps. It restores us to ourselves and to others, to our larger social body.
In this way, movement and mapping is not just a physical necessity but an emotional, social, and spiritual imperative.
Sources:
At the time, I saw ataxia as the way it’s defined: as a degenerative disease: https://www.ataxia.org/what-is-ataxia/
They may continue to perceive detailed information about where the limb is located in space: Tuthill, J. C., & Azim, E. (2018). Proprioception. Current biology : CB, 28(5), R194–R203. https://doi.org/10.1016/j.cub.2018.01.064
When someone loses a hand, for example: How We Map Our Bodies from Infancy. (2015, August 11). Cognitive Neuroscience Society. https://www.cogneurosociety.org/body_maps_marshall_aug15/. See also: Yang, T. T., Gallen, C. C., Ramachandran, V. S., Cobb, S., Schwartz, B. J., & Bloom, F. E. (1994). Noninvasive detection of cerebral plasticity in adult human somatosensory cortex. Neuroreport, 5(6), 701–704. https://doi.org/10.1097/00001756-199402000-00010.
Researchers propose that S2 processes high-level conceptual information: (Bretas et al., 2020 or use specific ones) Bretas, R. V., Taoka, M., Suzuki, H., & Iriki, A. (2020). Secondary somatosensory cortex of primates: beyond body maps, toward conscious self-in-the-world maps. Experimental brain research, 238(2), 259–272. https://doi.org/10.1007/s00221-020-05727-9.
Despite its diminutive size, the cerebellum contains an estimated 50 to 80 percent: Herculano-Houzel, S. (2010). Coordinated scaling of cortical and cerebellar numbers of neurons. Frontiers in Neuroanatomy, 4, 12. https://doi.org/10.3389/fnana.2010.00012
The cerebellum hosts a number of maps of its own: van Es, D. M., van der Zwaag, W., & Knapen, T. (2019). Topographic Maps of Visual Space in the Human Cerebellum. Current biology : CB, 29(10), 1689–1694.e3. https://doi.org/10.1016/j.cub.2019.04.012
New discoveries reveal three distinct representations for working memory, language, emotional processing, and social cognition: Guell, X., Gabrieli, J., & Schmahmann, J. D. (2018). Triple representation of language, working memory, social and emotion processing in the cerebellum: convergent evidence from task and seed-based resting-state fMRI analyses in a single large cohort. NeuroImage, 172, 437–449. https://doi.org/10.1016/j.neuroimage.2018.01.082