Summary
Three Brains: Balancing the Left and Right Hemispheres for a Healthier Life
It could be argued that we have three brains: the right hemisphere, the left hemisphere, and the many neurons in our gut—equivalent in number to a dog’s brain. Today, I’d like to focus on the differences between the left and right hemispheres of the brain. These distinctions are explored brilliantly by Iain McGilchrist in his books The Master and His Emissary and The Matter with Things. He describes fascinating cases of people with damage to the right hemisphere and the profound effects this has on behaviour.
Examples of Right Hemisphere Damage
Consider these striking illustrations:
- When asked to draw a clock, they might only draw half of it.
- Given a plate of food for dinner, they’ll eat only from one side.
- In more serious cases, they might deny ownership of their own arm, claiming it belongs to their mother or the doctor.
- Asked to draw an elephant, they can sketch individual elements—like the trunk, a leg, or the tail—but fail to integrate them into a coherent whole.
These examples reveal key insights into how the hemispheres function. The left hemisphere is detail-oriented, focused on grasping and manipulating the world piece by piece. In contrast, the right hemisphere perceives the big picture, understanding how elements connect and form a unified whole.
For comparison, when someone with left hemisphere damage draws an elephant, they produce a recognizable overall shape but with far less internal detail. This highlights the complementary roles: the left excels at precision, while the right provides holistic context.
Insights from Split-Brain Experiments
These differences become even clearer in the work of Michael Gazzaniga, who studied patients with severe epilepsy. To prevent life-threatening seizures, surgeons severed the corpus callosum—the bundle of fibres connecting the hemispheres. This procedure saved lives but created a unique window into brain function.
In one experiment, information presented to the right eye is processed by the left hemisphere, and vice versa for the left eye. Researchers gave participants a puzzle involving cubes that needed to be arranged to match a target image.
- With both hands free, the hand controlled by the right hemisphere (the left hand) would start solving the puzzle holistically.
- However, the left hemisphere’s hand (right hand) would interfere, fiddling with individual cubes without grasping the overall pattern—disrupting the progress.
Applying This to Our Lives
Why discuss these examples? Because they offer practical tools for becoming our healthiest selves. Most of us don’t have brain injuries, but our lives can still feel out of balance. We might not know why things feel “off,” and hemispheric imbalance could be part of the puzzle.
Take a business scenario: If you’re fixated on KPIs—ticking boxes on a spreadsheet to hit targets—you’re leaning heavily on the left hemisphere. This detail-focused mode can cause you to overlook the human element. Perhaps a team member is welcoming a new child or grieving a loss. Without the right hemisphere’s broader view, you treat people as data points rather than fully conscious individuals navigating life’s complexities.
This imbalance stems from modes of attention: The right hemisphere attends to the whole, while the left zooms in on parts. We need both—the left’s precision is invaluable—but overemphasizing it erodes holistic well-being.
In personal life, consider creating a spreadsheet for workouts or habits: “If I just check these boxes, everything will be fine.” You might succeed, yet still feel unfulfilled. What’s missing? The right hemisphere reminds us of our embodied humanity—the warmth of sun on skin, the flutter of a butterfly, a bird on a branch, the flow of a river, or music stirring deep emotions. It honours connections with loved ones, offering respect, affection, and love.
In extreme right-hemisphere compromise, people may even perceive others as automatons—lacking vitality or consciousness. The left sees mechanisms; the right sees living essence. Without balance, life loses its vibrancy.
The Bigger Picture: Technology, AI, and Society
To thrive, we must consciously attend to both: Dive into details when needed, but regularly lift our gaze—out the window, toward mountains or sea—to embrace the full human experience.
This principle applies broadly, even to the rise of technology and AI. AI exploded into public awareness with tools like ChatGPT, and its trajectory feels unpredictable. Will it achieve general intelligence? Could it deem humanity obsolete? We’ve arrived here through left-hemisphere dominance: Brilliant engineers solving intricate problems (“How do we build this system?”) without pausing for right-hemisphere questions (“Should we? Does this serve humanity?”).
Consider job displacement: Replacing 90% of roles with machines disrupts meaning and purpose. Yet the focus remains on “what can be done,” fueled by profit motives like the AI gold rush. Even immense wealth—say, becoming the richest person alive—can’t compensate if it erodes shared human experience. Studies show happiness plateaus around $60,000 annually once basics are covered; beyond that, money adds little joy.
This left-dominant thinking fuels a global anxiety crisis. But I caution against fixating on macro events we can’t control. Instead, focus on your sphere: What needs attention in your health, relationships, or community? Use the right hemisphere to see the whole—what do your loved ones need? Then deploy the left’s skills to act.
Final Thoughts
A healthy life demands balance: Honour the big picture to infuse vitality, then harness details to make it real. Thank you.