Neuroscience
The Brain Mechanics of Superfluid Coordination
Midbrain "relay stations" modulate motor loops linked to fluid performance.
Posted December 7, 2021 Reviewed by Abigail Fagan
Key points
- The cerebrum and cerebellum both have left and right hemispheres. These four hemispheres are connected via the midbrain.
- The midbrain contains neural circuitry and "motor loops" that facilitate bidirectional feedback between the cerebrum and cerebellum.
- The subcortical basal ganglia sit atop the midbrain, just below the cerebral cortex, and help to coordinate fluid motor skills.
"Becoming a neurosurgeon was a direct consequence of my eye for the ball while playing racket sports." —Richard Bergland, M.D., 20th-century neuroscientist, brain surgeon, and world-class tennis & squash player.
When I was a rookie tennis player in the 1970s, my late father, Richard Bergland (1932-2007), a neuroscientist who also did neurosurgery, coached me using drills designed to optimize whole-brain functions. Dad's favorite drill was having me serve and volley using my left hand. Because I'm right-handed, he believed that if I only ever practiced racket sports using my dominant hand that I'd be a "half-brained" player.
For my book, The Athlete's Way, my father and I created a split-brain model we called "up brain-down brain." This framework focused on optimizing the structure and functional connectivity of both cerebral hemispheres (up brain) and both cerebellar hemispheres (down brain).
Our purposely simplistic split-brain model vaguely refers to the "midbrain" as a bidirectional relay station between the cerebrum and cerebellum.
Notably, the right cerebellar hemisphere works with the left cerebral hemisphere to coordinate movements on the right side of the body and vice versa.
When a right-hander plays tennis using their dominant hand, the neural networks that connect the right cerebellar hemisphere to the left cerebral hemisphere become fortified. In contrast, the cross-lateral connectivity between the other two "up-down" hemispheres may atrophy if not actively engaged.
For a right-hander, doing left-handed tennis drills (and vice versa for a left-hander) can help to optimize whole-brain functions by keeping potentially underused cerebral and cerebellar motor loops engaged.
"Paralysis by Analysis" Disrupts Fluidity and Causes Athletes to Choke
Overthinking by relying too much on cerebral functions causes athletes to choke. Therefore, my father viewed the key to creating flow state experiences and what I call "superfluidity" (a state of frictionless flow) as being associated with less cerebral thinking and more cerebellar automaticity.
Two quotes sum up this cerebral-cerebellar framework. First, "There's a thing in sports called 'paralysis by analysis,'" by Arthur Ashe. Second, "Unclamp in a word your intellectual machinery and let it run free; the service it will do you will be twice as good," by William James from The Gospel of Relaxation. (See "Superfluidity and the Synergy of Your Four Brain Hemispheres.”)
Interestingly, my father also viewed learning to touch type (without looking at the keyboard) as a way to strengthen whole-brain functions. The ambidextrous nature of using all ten fingers like a well-oiled machine allows touch typists to "let their fingers do the thinking" by equally engaging all four brain hemispheres.
When my father typed the manuscript for his book, The Fabric of Mind, he prided himself on still being able to touch type over 100 words per minute on the same Royal Quiet Deluxe typewriter he'd used in college.
When I was in high school, Dad encouraged me to practice my touch typing skills just like I'd practice my tennis serve with my non-dominant hand. His educated guess was that tool-use training exercises kept the interhemispheric functional connectivity throughout the entire brain "well lubricated."
Recently, a team of researchers (Thibault et al., 2021) found that tool-use training improves language skills by tapping into the basal ganglia's syntactic processes and neural systems. Syntax means "arrange together" in Greek. Motor loops rooted in the basal ganglia facilitate fluid muscle movements via midbrain motor circuits and appear to help us arrange sequences together in a well-coordinated way. (See "Can Mastering Tool Use Make You a Better Wordsmith?")
As mentioned, when my father coached me on ways to optimize brain structure and function, he tended to focus on the cerebrum ("big brain") and cerebellum ("little brain"). But the midbrain—which acts as a relay station that connects the neural circuitry between both cerebral and cerebellar hemispheres—always seemed like an afterthought.
Motor Loops Rooted in the Basal Ganglia Facilitate Fluid Performance
In the past few days, another recently published study (Guenther, 2021) caused me to rethink the importance of midbrain "relay stations" and, in particular, the role that the cortico-basal ganglia-thalamocortical motor loop (cortico-BG loop) plays in facilitating fluid coordination. (See, "Neurological Research Changes Our Understanding of Stuttering.")
Frank Guenther of Boston University found that anomalies in the basal ganglia's neural circuitry cause speech disfluency, or stuttering. His theory posits that disfluent speech happens because the cortico-BG loop plays a pivotal role in the initiation of speech motor programs. Interestingly, stutterers with the least severe symptoms tend to have greater functional connectivity between the cerebellum and the cerebrum's orbitofrontal cortex (OFC).
Hypothetically, from an athletic perspective, one could speculate that the same initiation problems rooted in the cortico-BG motor loop that cause discombobulated speech initiation might also play a role in fumbling or choking on the playing field during sports. And on the flip side, the same compensatory brain mechanisms that improve speech fluency may also play a role in superfluidity during Bolshoi-ballet levels of peak performance.
I'm still digesting the above-mentioned research findings and contemplating how speech initiation problems rooted in the basal ganglia fit into the "Super 8" loops represented in my rudimentary hand-drawn brain map from 2009. For the past decade, decoding this quirky brain map has been an ongoing quest and remains a work in progress.
Although it's clear that I've been overlooking the basal ganglia for too long, I'm still trying to figure out how all the pieces of this puzzle fit together. Stay tuned for more evidence-based research on how motor loops rooted in the basal ganglia help us create flow states and facilitate superfluid performance.
References
Simon Thibault, Raphaël Py, Angelo Mattia Gervasi, Romeo Salemme, Eric Koun, Martin Lövden, Véronique Boulenger, Alice C. Roy, Claudio Brozzoli. "Tool Use and Language Share Syntactic Processes and Neural Patterns in the Basal Ganglia." Science (First published: November 12, 2021) DOI: 10.1126/science.abe0874
Frank Guenther. "A Neurocomputational View of Developmental Stuttering." The Journal of the Acoustical Society of America (First published online: November 18, 2021) DOI: 10.1121/10.0007800
Soo-Eun Chang and Frank H. Guenther. "Involvement of the Cortico-Basal Ganglia-Thalamocortical Loop in Developmental Stuttering." Frontiers in Psychology (First published: January 28, 2020) DOI: 10.3389/fpsyg.2019.03088
Kevin R. Sitek, Shanqing Cai, Deryk S. Beal, Joseph S. Perkell, Frank H. Guenther, and Satrajit S. Ghosh. "Decreased Cerebellar-Orbitofrontal Connectivity Correlates with Stuttering Severity: Whole-Brain Functional and Structural Connectivity Associations with Persistent Developmental Stuttering." Frontiers in Human Neuroscience (First published: May 03, 2016) DOI: 10.3389/fnhum.2016.00190