Learning from my own hard-won experience
I used to love the simplicity of it. Right brain for creativity, left brain for logic. It gave me a neat way to explain why some of my clients struggled with balance in their lives.
It also gave me a handy excuse for my own lapses: โAh, thatโs just my left brain overdoing it.โ
But neatness and truth rarely line up. And in this case, neatness has misled us for decades.
Where the myth came from
Back in the 1960s, neuroscientists studied โsplit-brainโ patientsโpeople whoโd had their corpus callosum cut to treat severe epilepsy. These studies (notably by Roger Sperry and Michael Gazzaniga) showed that certain tasks could be localised: language more often on the left, spatial awareness more often on the right.
But popular psychology took these partial truths, stripped them of nuance, and sold them as identity labels: โYouโre left-brainedโanalytical, rational. Youโre right-brainedโcreative, intuitive.โ It was catchy. It sold books. It gave workshops a framework.
And it was neurobollocks.
What neuroscience actually shows
Modern brain imaging has shredded the myth.
- Both hemispheres are deeply interconnectedโvia around 200 million fibres in the corpus callosum.
- Creativity and logic light up networks across both hemispheres, not neatly divided.
- Even language, the poster-child of left-brain dominance, involves right-hemisphere contributions to prosody, metaphor, and context.
As Banich & Compton (2018) put it, โhemispheric specialisation exists, but the brain does not divide people into types.โ
Why this matters in psychotherapy
The problem isnโt just scientific inaccuracy. Itโs how the myth is used.
Iโve sat in workshops where clients were labelled โtoo left-brainedโ to connect emotionally. Iโve seen managers write off employees as โnot creativeโ because of their supposed hemisphere bias. AndโtruthfullyโIโve been guilty of repeating the shorthand myself when I should have known better.
But these myths shape identity. They can box people in, or worse, let therapists sound authoritative while drifting further from real science.
A more honest takeaway
Hemispheric differences are fascinating. But they donโt divide us into types. A better metaphor: the hemispheres are like band membersโdifferent instruments, but always playing together.
The insight I had to learn the hard way? Clients donโt need to be told theyโre left-brained or right-brained. They need help integrating, experimenting, and finding flexibility across the whole orchestra. Thatโs where growth happens.
References
- Banich, M. T., & Compton, R. J. (2018). Cognitive neuroscience (5th ed.). Cambridge University Press.
- Corballis, M. C. (2014). Left brain, right brain: facts and fantasies. PLOS Biology, 12(1), e1001767. https://doi.org/10.1371/journal.pbio.1001767
- Gazzaniga, M. S. (2000). Cerebral specialization and interhemispheric communication: Does the corpus callosum enable the human condition? Brain, 123(7), 1293โ1326.