Children who suffer perinatal strokes may be left with large holes or lesions where brain regions should be. Many are severely disabled. But some are not disabled at all.
One woman, Helen Santoro, was so little affected by the lack of a left temporal lobe that she got dropped from a research study of the aftermath. Now a science writer, she published an article last week in the New York Times about her efforts to understand and unravel the mystery.
Perinatal stroke is often discovered, as in her case, when the newborn child has trouble with breathing or sucking reflexes. A brain scan showed “a huge hole’ where her left temporal lobe should have been, just above the ear. Because that lobe is thought to be involved with “a wide variety of behaviors, from memory to the recognition of emotions, and considered especially crucial for language,” her mother was advised as follows by medical professionals:
They told her I would never speak and would need to be institutionalized. The neurologist brought her arms up to her chest and contorted her wrists to illustrate the physical disability I would be likely to develop.
But month after month, I surprised the experts, meeting all of the typical milestones of children my age. I enrolled in regular schools, excelled in sports and academics. The language skills the doctors were most worried about at my birth — speaking, reading and writing — turned out to be my professional passions.Helen Santoro, “The Curious Hole in My Head” at New York Times (September 4, 2022)
Santoro did so well that, having developed an interest in neuroscience, she ended up interning in the lab of Ruth Nass, the pediatric neurologist who had dropped her from the study. But here’s the challenge she poses:
My case is highly unusual but not unique. Scientists estimate that thousands of people are, like me, living normal lives despite missing large chunks of our brains. Our myriad networks of neurons have managed to rewire themselves over time. But how?Helen Santoro, “The Curious Hole in My Head” at New York Times (September 4, 2022)
In fact, she was spurred to write about her personal experiences by a recent story in Wired about a woman of normal mental development who was also missing her left temporal lobe. (See “Woman missing key language part of brain scores 98% in vocab test”.)
As Santoro puts it, “For more than a century, the left hemisphere of the brain has been considered the center of language production and comprehension.” But some neuroscientists now think that language processing is not limited to specific brain regions:
“I believe that language in the brain is distributed throughout the entire brain,” said Jeremy Skipper, the head of the Language, Action and Brain Lab at University College London (and my former college psychology professor).Helen Santoro, “The Curious Hole in My Head” at New York Times (September 4, 2022)
Neurology, it appears, is not an exact science. In any event, Santoro found herself part of a project sponsored by MIT cognitive neuroscientist Evelina Fedorenko, along with seven other participants with significant neurological variances. The current best guess is that the human brain is very plastic in infancy and may just rewire around a deficit.
For example, the woman featured in Wired had adapted by switching sides. She processed language via the right temporal and frontal lobes, not the left ones. But Santoro’s adaptation is harder to account for: “A preliminary analysis of the scans showed that, even without a left temporal lobe, I still process sentences using my left hemisphere.” Dr. Fedorenko thinks that there is perhaps “enough healthy tissue in the back for the language system to take root.”
Two things we know for sure: Brain scanning, far from confirming a materialist interpretation of neuroscience, is revealing many instances of people who function normally with brains that are missing key components — or with only half a brain (or maybe less).
Yet, at the same time, a foundation of modern neuroscience is that the mind is simply what the brain does. And, while the question is not raised in the otherwise most informative New York Times piece, that simply does not appear to be true.
Eventually, theory and evidence will need to meet up.
You may also wish to read: A neurosurgeon on why some people function with only half a brain. The study results are reassuring and they point to two larger truths. First, the mind is not the brain and second, people tend to see the mind–brain relationship in terms of the cultural conceptions that matter to them.