According to a range of authorities from Shakespeare to Blondie, our hearts generate our defining emotional and moral qualities. Whether it’s work, relationships or politics, we follow our hearts, even as we try not to let them rule our heads.
Except, of course, we know damn well that while our hearts may keep us alive, they don’t govern our selves. Soft hearts, hard hearts, warm hearts, cold hearts, brave hearts, true hearts, hearts of glass, achy-breaky hearts: we know that they’re all metaphors, that the heart is just a pump that can be transplanted from one human being to another with no transference of personality, loves, or passions. If you want to discuss an organ in philosophical rather than mechanical terms, you need to start looking at the brain.
We may not wear little stylised brains on chains around our necks, but we’re certainly reading more and more books about them. Norman Doidge, the author of The Brain That Changes Itself, enthralled the crowds at last year’s Sydney Writers’ Festival with his discussions on "neuroplasticity", the ability of the brain to restructure itself throughout the course of our lives. This year’s festival features another author interested in the brain, Perminder Sachdev, whose book The Yipping Tiger and other tales from the neuropsychiatric clinic was released last year.
Sachdev is the director of the Neuropsychiatric Institute at the Prince of Wales Hospital in Sydney. He has published a clutch of scholarly papers and books, but The Yipping Tiger is his first book for a general readership.
In conversation at the Institute that provides the book’s setting, Sachdev tells me that he had begun writing up a few of his case studies some time ago. He gestures around his office at the books and furniture and paraphernalia of his day job and I believe him when he says he had never had the time to turn them into a full-length book until recently. And The Yipping Tiger does have the air of a book that has evolved over a long period of reflection; it has been two decades since Sachdev decided that he wanted to explore the relationship between the brain and the mind.
As a medical student, Sachdev opted for psychiatry rather than neurology, because he thought it offered the scope for examining "the human condition". Taking up the position at the Neuropsychiatric Institute was his response to "the realisation that just as the neurology of my training years was mindless, the psychiatry I had adopted as my profession was largely brainless". The mind and the brain had come to be considered as separate entities, with psychiatrists focusing on the former and neurologists the latter. At the Neuropsychiactric Institute, patients’ mental and neurological conditions could be treated in tandem.
The Yipping Tiger describes Sachdev’s encounters with a range of patients whose conditions range from golfer’s "yips" to brain injury to Tourette Syndrome. The young man in search of drugs for cognitive enhancement that he hopes will make him exceptional, out-of-the-ordinary; the reserved, sweet-natured young woman who cannot restrain her expletive-laden abusive outbursts; the patient who struggles to control his "alien hand syndrome" after brain surgery seems to give his limb a mind of its own: Sachdev uses their stories to reflect on questions about the relationship between the mind and the brain and the implications of neurological disorders for the concept of free will. Can we really be said to have free will when our minds can be so convincingly overruled by the neurological functioning of our brains?
Now, sitting in his office, Sachdev returns to the subject of free will, explaining that it is possible to detect activity in the relevant parts of the brain microseconds before we form any conscious intent to perform even a simple action, like picking up a pen. For the patient with "alien hand syndrome", such activity can be sufficient to generate movement against the will of the patient, who can be left, like Dr Strangelove, with one hand slapping down the disobedient actions of the other.
I had never, ever been conscious of my brain directing the actions of my hand until suddenly, it failed to perform the same simple task that Sachdev is enacting before me, pointing from his head to his hand, lifting the pen from the table. I was about to begin teaching an undergraduate Asian studies class and I tried to pick up a pen to mark the date on the attendance sheet. Somehow, the transmission signals between my brain and the right hand side of my body had broken down. There was nothing wrong with my hand, except that when I told it to pick up the pen, it could only manage a clumsy fumble. My "alien hand" was not moving against my will — but it wasn’t moving when I told it to move, either.
Of course, I thought tumour, followed by imminent death, followed by I’d better get to the doctor once we get this discussion on Confucius out of the way. It wasn’t a tumour — it was multiple sclerosis, which sounded like a mild dose of the flu, by comparison. But this is still my brain we’re talking about, and I can’t help finding that just a wee bit existential. Lying with my head enclosed in an MRI machine I have to tell myself over and over again that it is only my brain being scanned, and not my soul. The machine can detect lesions and disease progression, but it cannot read my inner-most self, my soul. Wherever my soul might reside, it’s not inside my skull.
So it comes as a jolt to read in Sachdev’s book about 17th century anatomist Thomas Willis, who was among those who believed that the soul resided in the corpus callosum. I’m only slightly reassured to read in the next sentence that the corpus callosum is now conceptualised as a bridge between the hemispheres of the brain, rather than as the seat of the soul. I seek further reassurance from Sachdev — what about the soul?
"I only really mention the soul in parentheses," he tells me. "Once you start talking about the soul, you’re moving away from the realm of neuroscience."
But the mind — yes, the mind exists, intimately enmeshed with the brain. Some areas of our brains generate impulses that run counter to our minds’ sense of what is appropriate or moral, but other areas of the brain should have the capacity to suppress those impulses — and, Sachdev says, free will can be defined as the ability to refrain from turning impulse into action. Individuals with some medical conditions lose this capacity, and then society must decide to what extent they can be held responsible for the consequences. Absolute free will, Sachdev concludes, is a "myth", but even those whose free will is compromised by their neurological conditions retain their personhood, their selves.
Even if it does not attempt to analyse the soul, The Yipping Tiger raises profound questions about how neurology impacts upon who we are. Sachdev portrays his patients as three-dimensional characters rather than as a series of freaks, and in discussing their brains and minds, he invites us to reflect upon our own. Perhaps his book will start a fad for brain-shaped jewellery and fluffy cushions — although I’m thinking, probably not. Another neurological mystery: why does the idea of wearing a brain locket seem so disturbing, when wearing a heart locket only seems saccharine?