A staple of coffee room chatter has been left brain vs. right brain thinking. You know, “He’s one of those left-brain types; he’d fire us all to save money!” or “She’s really a right-brain kind of person so if something looks beautiful, she probably isn’t thinking about what would happen if…”
Left brain, right brain… Its one of those complex cultural concepts that starts in conventional science fact, explodes into pop psychology chatter, and then settles into a small, murky world that can only be navigated by serious thinking.
First, vertebrates generally have brains divided into two lobes, an arrangement that may go back half a billion years. The right hemisphere usually controls the left side of the body and vice-versa.
In addition to that, different parts of the brain have specialties and that can come with a cost. As Robert H. Shmerling a senior editor at Harvard Health Publishing, explains, the effects of brain damage show clearly what the different halves do. But then he goes onto say,
But for more individual personality traits, such as creativity or a tendency toward the rational rather than the intuitive, there has been little or no evidence supporting a residence in one area of the brain. In fact, if you performed a CT scan, MRI scan, or even an autopsy on the brain of a mathematician and compared it to the brain of an artist, it’s unlikely you’d find much difference. And if you did the same for 1,000 mathematicians and artists, it’s unlikely that any clear pattern of difference in brain structure would emerge. – Robert H. Shmerling, “Right brain/left brain, right?” Harvard Health Publishing, March 24, 2022
Humans are not machines; we are each an integrated mind and body, changing through time and adapting to a variety of circumstances. For example, while most humans are right-handed, about one in ten is left-handed. Lefties, according to a large 2021 study, “often use different sides of their brains for working memory, language, vision, and hand control.” For that matter, about 1% of humans are ambidextrous. Of course, it’s unclear how many ambis are lefties quietly adapting to a right-handed world. At any rate, lefties and ambis are generally excluded from brain research. That omission might unintentionally create the notion that right-handedness is an architectural feature of the human brain.
And, just to confound matters, brain imaging continues to identify humans living roughly normal lives who are missing large or key parts of their brains.
Neuroscience is not an especially rewarding field for the pursuit of dogma
Most neuroscience sources are now appropriately cautious about claims for the left brain personality vs the right brain personality. For example, a classic consumer source, Healthline, tells us,
Whether you perform a logical or creative function, you receive input from both sides of your brain. For example, people credit the left brain with language, but the right brain helps you understand context and tone. The left brain handles mathematical equations, but the right brain helps out with comparisons and rough estimates.
General personality traits, individual preferences, or learning styles don’t translate into the notion that you’re left-brained or right-brained. – Ann Pietrangelo, “Left Brain vs. Right Brain: What Does This Mean for Me?” HealthLine, May 9, 2022
Even debate opponents agree that the situation is fuzzy
A recent exchange between cognitive scientist Scott Barry Kaufman and psychiatrist and writer Iain McGilchrist at IAI.TV shows how murky the topic is. Kauffman, author of Transcend (TarcherPerigee, 2020), assures us,
The latest findings from the real neuroscience of creativity suggest that the right brain/left brain distinction does not offer us the full picture of how creativity is implemented in the brain. Creativity does not involve a single brain region or single side of the brain.
Instead, the entire creative process– from preparation to incubation to illumination to verification– consists of many interacting cognitive processes (both conscious and unconscious) and emotions. Depending on the stage of the creative process, and what you’re actually attempting to create, different brain regions are recruited to handle the task. – Scott Barry Kaufman, “Creativity is not a right brain phenomenon,” IAI.TV, 12th July 2023.
While McGilchrist, author of The Matter with Things (Perspectiva Press, 2021, 2 volumes), thinks that the right side of the brain really does handle creativity, he nonetheless admits, “Of course, and for the umpteenth time, both hemispheres are involved in everything we do, and are in normal subjects always active together.” He then points up some of the difficulties with the whole area of research:
A central problem in the research into brain correlates is that it is difficult, to say the least, to get people to ‘be creative’ to order, for the purposes of experiment: great artists and original scientific thinkers alike make clear that creativity cannot be summoned in this way. As a result, routine tasks, such as finding as many uses as possible for a coat-hanger, substitute for what was done by Mozart. … Many of the studies on creativity are wholly or partly linguistic in nature, involving reading, speaking or generating words – or all three. Language alone inevitably recruits more left hemisphere areas than a non-linguistic creative task, skewing our assessment of creativity per se. – Iain McGilchrist, “The right brain is essential to creativity,” IAI.TV, 13th July 2023.
In short, we probably can’t really know. It’s not even clear what there is to know.
The main difficulty would seem to be this: The type of neuroscience research that offers correlates for bowling, filing, or choosing a sofa may never be suited to understanding Mozart. The risk then is not that we will know nothing but that we will know just enough to get it all wrong.
You may also wish to read: Does left brain-only thinking impoverish our mental world? How? A discussion of the left brain vs the right brain that avoids pop science can set us thinking, as psychiatrist McGilchrist and neurologist Dirckx show. Materialism impoverishes mind–brain discussions due to Egnor’s dilemma: If your hypothesis is that your mind is an illusion, then you DO NOT HAVE a hypothesis.