Source: Gwenaëlle Douaud, University of Oxford

Yesterday, I wrote a post, "Handedness May Sway Right Brain–Left Brain Language Regions," that was inspired by a new study (Wiberg et al., 2019) about how being left- or right-handed may influence the coordination of language processing regions in both cerebral hemispheres. The paper by Akira Wiberg and colleagues at the University of Oxford was published on September 5 in the journal Brain.

This blog post is a follow-up that explores the above-mentioned research on the functional connectivity of brain hemispheres and language function through the lens of my own life experience as a science reporter, blogger, jogger, and son of a 20th-century neuroscience pioneer.

In the 1970s, my late father, Richard Bergland (1932-2007), was chief of neurosurgery at Harvard Medical School's Beth Israel Hospital in Boston. Dad was also a who performed experiments to test various hypotheses based on bedside observations he'd make while treating human patients with damage to specific brain regions.

For example, patients with brain damage to particular areas in the left cerebral hemisphere often had trouble with language; this corroborated the 1960s split-brain model of Roger Sperry (1913-1994) which posited that language was a "left brain" function and nonverbal functions were " ."

Source: Viking/Public Domain

In the 1980s, my dad wrote and published The Fabric of Mind, which played an unintended role in perpetuating the pop psychology oversimplification of "left brain-right brain" and the regrettable phenomenon of labeling people more "right-brained" or "left-brained." Because my father was a small player in the genesis of this neuroscience myth (neuromyth), by the early 21st-century, after he'd retired professionally, Dad was eager to set the record straight by creating an entirely new split-brain model and distancing himself from "left brain-right brain."

In 2004, after breaking a Guinness World record by running six back-to-back marathons (153.76 miles) nonstop on a treadmill, I got a book deal with St. Martin's Press to write The Athlete's Way: Sweat and the Biology of Bliss. This book integrates neuroscience into actionable prescriptive advice for day-to-day life and peak sports performance.

Luckily, my father had plenty of time on his hands and served as the "medical expert." Together, we created an original split-brain model for the manuscript we called "up brain-down brain." Our goal was to shift the focus away from "left brain-right brain" and put the cerebellum (Latin for "little brain") in the spotlight. Cerebellar means "relating to the cerebellum" and is the sister word to cerebral.

The cerebellum coordinates finely-tuned motor coordination and is the seat of implicit muscle . Anything you learn to do automatically—such as riding a bike or touch typing without looking at the keyboard—is cerebellum dependent.

Source: Photo and illustration by Christopher Bergland circa 2009.

Notably, the right hemisphere of the cerebellum works with the "left brain" in the cerebrum to control muscle movements and fine-tune motor coordination on the right side of the body, and vice versa.

When someone who is right-handed suffers damage to specific "microzones" in the right cerebellar hemisphere connected to the left cerebral hemisphere, it is not uncommon for them to suddenly have difficulty with language and verbalization.

In 1998, Jeremy Schmahmann of Harvard Medical School's Massachusetts General Hospital published a landmark paper in the journal Brain about the impact of cerebellum damage on language and other non-motor functions and coined the game-changing term "Cerebellar Cognitive Affective Syndrome."

As a brain surgeon and neuroscientist, my father understood the importance of optimizing the functional connectivity between his cerebrum and cerebellum. In a meta-cognitive way, he also realized that having better coordinated brain hemispheres made it easier to fluidly handle medical instruments while performing delicate neurosurgical procedures on other people's brains.

Source: Kay Bergland, used with permission.

One way Dad made himself more ambidextrous was by playing tennis and squash with the "wrong" hand sometimes. Although my father was right-handed, he'd perform drills against a backboard using his left hand to keep the white fiber tracts that connected his brain hemispheres more robust. My father didn't want to become "too right-handed." He viewed "imbalanced handedness" like a lobster that has one over-sized claw, while the other atrophies. According to Dad, being too right-handed would make him "all thumbs" in the operating room.

From the day I was old enough to hold a racket, my father prided himself on being my tennis coach. Beginning at a very young age, he passed on neuroscience-based, sports-related lessons about handedness and hemispheric lateralization to me.

Because I'm a loner by nature, when I was a kid, I'd spend hours and hours every week practicing my tennis strokes against a backboard. Even though I'm a right-hander, much of my backboard tennis practice was spent playing with my left hand in an attempt to help my brain hemispheres become better coordinated.

I was a terrible high school student with a C- average; the only reason my GPA wasn't 1.0 is that I loved typing class and got an A+. Touch typing (without looking at the keys) is like a sport to me, and it comes naturally. That said, being a so-called "writer" does not come naturally to me.

Nevertheless, as a teenager, the challenge and skill required to type "The quick red fox jumps over the lazy brown dog" repeatedly, as fast as possible, on an IBM Selectric typewriter created a state of flow and put me in "the zone." This muscle memory stuck for life; touch typing is like riding a bike.

As a real-time example, this morning, I touch typed the rough draft for this post in a stream of consciousness state of mind in the predawn hours while sitting at my desk in complete darkness. At this point, the post is 900 words, and it's taken about a half-hour to write thus far.

Source: Pixabay

Now that this rough draft is complete and the sun is coming up, I'm chomping at the bit to go for a long jog and visualize how I want the layout to look on a digital screen. I'll also fiddle around with sentence structure in my mind's eye while jogging and take mental notes about specific phrasing I want to fix before posting online.

From years of road-tested experience, I've learned that jogging stimulates my imagination and facilitates the creative process—and this appears to be universal. It seems that bipedal aerobic movement optimizes the functional connectivity of all four brain hemispheres in ways that help people write better.

Blogger's note: I'm well aware this blog post isn't going to win a Pulitzer Prize for "excellence in journalism" and is "meh" by New Yorker writing-quality standards. But that's OK. It was fun and easy to compose; the ideas flowed from my mind through my fingertips in a way that felt "superfluid" and effortless.

Hopefully, this post will inspire anyone who pigeon-holes themselves as "only a right-brained, visual learner" (Rinaldi & Gurung, 2008)—or says "I'm too left-brained to be creative and think outside the box"—to realize that your daily habits can reshape the functional connectivity of your brain at any age.

Remember: When it comes to neuroplasticity and reshaping the hemispheric lateralization of your brain, white matter functional connectivity is never completely set in stone.