A neurosurgeon's delicate dance with the cortex
The cortex is the brain’s stage and its spotlight, a wrinkled sheet of grey matter where everything that makes us human performs. It is thin, standing only a few millimetres tall, and yet, it holds our language, laughter, memories, dreams, passwords, and grudges. Beneath it lies machinery; above it, personality. It’s the surface that thinks. If the brain were Mumbai, the cortex would be South Bombay—dense, opinionated, elegant, and convinced it runs the place.
A 28-year-old advertising executive named Tara came to me after her colleagues noticed that she would suddenly stop mid-sentence, stare into space, and then continue as if nothing had happened. “It’s not stress,” she told me. “Though working in advertising is basically paid stress.” Her MRI showed a small lesion in the left temporal cortex, the patch of brain that handles language and memory. A subtle cortical tumour. It wasn’t big enough to terrify, but mischievous enough to demand attention.
The cortex has the thickness of three credit cards placed on top of each other but with the complexity of the cosmos. Each square millimetre contains thousands of neurons, a buzzing marketplace of thoughts and impulses, all talking over each other in 220-volt enthusiasm. When a tumour grows there, it is like a loud neighbour moving into an already overcrowded apartment block. It’s no wonder, then, that the other residents—speech, comprehension, logic—start complaining.
We decided to remove the tumour. Tara was awake during surgery, so that we could test her speech while working near her language area. Awake brain surgery may sound dangerous to most people, but patients usually find it oddly peaceful. You feel no pain, and you get to talk while someone edits your neurons. Think of it as giving a live TED Talk from the inside of your own head.
Under the microscope, the cortex looked as it always does—pink-grey, shimmering, alive. Its folds rose and dipped like the Western Ghats seen from above. I mapped the surface with tiny electrodes. When she counted numbers and her speech area lit up on the monitor, we marked it safe. Then, millimetre by millimetre, I began removing the tumour, the soft, sticky, slightly rebellious tissue, from a place where words are born.
“Doctor,” she said mid-surgery, “are you sure you’re not deleting my imagination?”
“No,” I said. “Just the part that makes bad taglines.” The room laughed. For a moment, the theatre felt lighter, as if the brain itself were in on the joke. When we finished, the cortex looked serene again, its gentle ripples restored. Tara recovered beautifully. Her speech was intact, her sense of humour sharper than before.
A month later, she sent me an ad campaign she had worked on, with the tagline—“A mind is a terrible thing to waste, so I didn’t.”
The cortex is where we live, although we rarely think about it. It turns electricity into ideas, sound into language, light into meaning. It lets us write poetry, cook biryani, remember our exes, and occasionally forget their birthdays. It gives the brain personality, and with that, irony, that such a delicate film of matter can hold all the weight of who we are. When I look at it under the microscope, I often reaffirm to myself that this is the edge of existence. Below it are reflexes and rhythms; above it, everything that makes us sentient. The cortex is where biology becomes biography.
We, surgeons, tread lightly here. We don’t just cut tissue; we edit identity. Every millimetre saved might mean a preserved laugh, a recovered memory, or one more sentence someone will finish one day.
Tara’s MRI is now clear. Her career is back on track, her brain’s advertising budget restored. She still texts me sometimes, signing off, “To my favourite copy editor, the one who worked inside my head.” And I reply, “Just did some market research!”
The author is consultant neurosurgeon at Wockhardt Hospital, Mumbai.
mazdaturel@gmail.com @mazdaturel
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