I'm fascinated by the extremes of the human experience, partly because it is so far removed from our own experience of life. In another way, when you look at people who have neurological disorders or diseases, these are really nature's experiments. They are ways of trying to understand how the brain works for all of us. By extrapolation from looking at these extremes, we can learn about the workings of our own brains. That's very much the case across all the areas of my work, whether it be sleep disorders, neurology, or epilepsy—how we regulate our emotions, how we move, how we experience the world.
I never intended to be a storyteller; I intended to be a story listener, which is what we do daily in our clinics. Telling these stories generates empathy, creates understanding, and hopefully inspires the next generation to pursue careers as doctors, psychologists, and healthcare professionals, fostering a fascination with the brain similar to what Oliver Sacks did for me.
Dr. Guy Leschziner is the author of The Nocturnal Brain, The Man Who Tasted Words, and other books. He is a consultant neurologist and a Professor of Neurology and Sleep Medicine at the Institute of Psychiatry, Psychology and Neuroscience, King's College London. He sees patients with a range of neurological and sleep disorders, and is actively involved in research and teaching. He has presented series on sleep and neurology for BBC World Service and Radio 4. His latest book is Seven Deadly Sins: The Biology of Being Human.
THE CREATIVE PROCESS
So we've really been enjoying your body of work, your most recent book, Seven Deadly Sins: The Biology of Being Human. So much of what your life's work encompasses—from your books, The Man Who Tasted Words and The Nocturnal Brain—really touches on aspects that are at the core of what we're interested in here at the creative process. You've written about synesthesia and sleep disorders. What can extreme neurological conditions teach us about the human mind?
GUY LESCHZINER
Well, I'm fascinated by the extremes of the human experience, partly because it is so far removed from our own experience of life. In another way, when you look at people who have neurological disorders or diseases, these are really nature's experiments. They are ways of trying to understand how the brain works for all of us. By extrapolation from looking at these extremes, we can learn about the workings of our own brains. That's very much the case across all the areas of my work, whether it be sleep disorders, neurology, or epilepsy—how we regulate our emotions, how we move, how we experience the world.
THE CREATIVE PROCESS
It makes me realize that all of life, or all of perception, is a kind of metaphor. We talk about symbolic language; language is symbols. It creates a picture in our minds. It just reminds me that there's something very beautiful about creativity in the human mind. We're constantly inventing stories.
LESCHZINER
I think one of the things that, hopefully, my books illustrate is that everybody's mind is different. One of the amazing things about the human experience—and indeed what manifests in terms of art and creativity—is that when we have such different minds, that is why all this creativity and all this art is possible.
THE CREATIVE PROCESS
Artists, of course, have found inspiration from their dreams. What have your examinations of the dreaming life revealed about its role in creativity?
LESCHZINER
There are many artists and musicians who have sought inspiration in their work. REM sleep, or dreaming sleep, has led to lots of songs and works of art that have been inspired by some sort of dream experience. Clearly, something happens in sleep that leads to the brakes coming off the creative process. There are parts of the brain that we suppress during waking life that become unsuppressed at night.
THE CREATIVE PROCESS
It's so fascinating to think about these blended states. It makes me think of your other book, The Man Who Tasted Words, and the subject we were touching on a little bit: synesthesia. We hear a lot about it from musicians and poets. It’s right there; it's blended all the time. You've met some really interesting synesthetes. For example, they can taste the flavors of words—like Tottenham Court Road has a flavor. It hints that our combination of senses can create a kind of reality that is, in some sense, a lie of the senses for the sake of efficiency.
LESCHZINER
Synesthesia covers a broad range of phenomena, but at its core, perhaps the most striking feature is the merging of different senses. Some people can taste words; others can see sounds. One person I describe in that book is actually a concert pianist. When she plays certain notes, keys, or chords, she sees colors in her vision or feels sensations over her body associated with that music. What all these individuals reflect is that our reality is entirely a function of how our brain works. Synesthetes have normal brains; there’s nothing wrong with their brains—it’s just that their brains are hyper-connected. Their experience of the world is very different from ours, which I think is magical and must give them a fuller experience of life, but it can also be very distracting. You can understand why individuals with synesthesia may be more creatively gifted; the number of synesthetes who are writers, poets, or musicians is indeed very high.
THE CREATIVE PROCESS
What have your studies and writings taught you about the nature of memory? You talk about having not quite accurate memories or that memory is a kind of creative process.
LESCHZINER
Sleep is really important for memory. We think that one of the primary functions of sleep is to consolidate memories, both autobiographical and emotional. One of the theories about why we dream is that it helps clean up our memories and rid them of their emotional content, which is why some researchers have termed sleep a form of overnight therapy. But one of the other theories about dreaming is that while we're dreaming, we are tweaking our model of the world. The brain doesn’t just interpret our senses; it also works as a prediction machine. We expect what we’re going to see and experience, and when our senses tell us something different from our expectations, we adjust our expectations. It’s difficult to do that when we’re awake because we’re processing many impulses from our surroundings. But when we’re in dreaming sleep, when we’re offline, that’s the time to integrate our experiences of the day into our model of the world. So, it’s the adjustment of how we understand reality that may be happening in REM sleep.
THE CREATIVE PROCESS
I think that’s definitely true. There are many ways we can learn outside of the classroom, and one of those ways is through your books and programs. We've been discussing inner landscapes and the beauty of the human brain and imagination. Could you reflect on our outward environment? Many speculate that our disconnection with the natural world causes us to lose inner harmony, calm, and focus. I’d love to hear your reflections on the beauty and wonder of the natural world and why that is beneficial for our minds.
LESCHZINER
Most of us live in urban environments that are busy, exciting, and full of stimuli, but they can also be dirty, noisy, and distracting. In many respects, it's a wonderful place to live. However, it’s not particularly conducive to calm, relaxation, or mindfulness. There’s an increasing body of medical literature tying mindfulness-based approaches to better brain and physical health. We need to try to introduce aspects of nature—calm and green spaces—into our cities. I think that will be good for our health, and we'll likely focus more on those aspects of urban living in the future.
THE CREATIVE PROCESS
There are obviously benefits. With AI and imaging, it’s hard to interview some of the people you study if their behavior occurs while they are sleeping; they don’t remember it afterward. Will these advances in technology help you unlock those mysteries?
LESCHZINER
One of the reasons we’ve made leaps forward in understanding sleep is due to technological advances. AI is undoubtedly going to help that process. As you mentioned, one of the difficult things we face is extracting subjective experiences from individuals who are sleeping; it’s almost impossible. We rely on other modalities like imaging and electrical activity, along with a whole range of other techniques and technologies, to interrogate the human brain. AI will have a role in that.
THE CREATIVE PROCESS
I think that's very insightful, as it shows how more isolated cases can tell us about traditional sleep patterns for people who don’t have abnormalities in their own sleep. Building off that regarding your book, The Nocturnal Brain, I noted you mentioned sleepwalking and how certain individuals have different parts of their brain awake while others are asleep. You referred to the cingulate cortex and prefrontal cortex. Given this, how might frequent sleepwalking episodes disturb someone's ability to differentiate between wakefulness and sleep?
LESCHZINER
Wake and sleep exist on a spectrum. We know that even while we're awake, there are small areas of our cerebral cortex that simulate sleep. While you and I are chatting, there are areas in both of our brains probably dipping in and out of sleep. Sleepwalking, too, is a significant spectrum. Some individuals may do very simple things like sit up in bed, look around, and then go back to sleep. Others might prepare an entire meal or drive a car in their sleep. This behavioral spectrum reflects how different amounts of the brain need to be active. For someone riding a motorbike, for example, a significant portion of their brain needs to be awake to see hazards, follow signs, navigate, and maintain balance. But for others, the bits responsible for memory or rational thinking might not be active, leading to just simple actions while the rest of the brain remains asleep.
THE CREATIVE PROCESS
We’re approaching the 100th anniversary of the rise of fascism in the last century. You discussed it at the beginning of Seven Deadly Sins. You’re the child of Holocaust survivors, and I wonder what your reflections are on this and how your upbringing, having been born in Germany, influenced your view of the world and your pursuit of neurology.
LESCHZINER
I think what’s going on in the world is very deeply worrying. I worry for my children and for society as a whole. I hope that the pendulum will eventually swing back, as it has throughout human history. However, it is very concerning indeed. My upbringing was atheistic, rooted in a Germanic Lutheran perspective on right and wrong. That perspective fueled some of the life choices I made, with the goal of making the world a little bit better. I’m not saying I have made the world better, but I believe we should strive to improve society for the sake of others, not just for personal gain. I try to do this through my work as a clinician. I remember reading The Man Who Mistook His Wife for a Hat by Oliver Sacks as a 15-year-old and finding it fascinating. It raised concepts of what it means to be human in neurological terms that I had never considered before. My interest in neurology and neuroscience was sparked by books like Sacks's, which also inspired me to write. I don’t think I do it as well as he did, but if one person reads one of my books and thinks, “This is a fascinating area I want to pursue,” then I’ve done my job.
THE CREATIVE PROCESS
We should also mention that, while we've focused on your books, you're a storyteller and presenter. You've presented programs on BBC Radio 4 and BBC World Service about the mysteries of sleep, the senses, and phantoms in the brain. You move from the listening and storytelling process one-on-one with patients to writing your stories down. What have these different storytelling processes taught you about communicating medicine and science?
LESCHZINER
I never intended to be a storyteller; I intended to be a story listener, which is what we do daily in our clinics. We listen to patients' stories, write them down, and try to understand them in a medical context to achieve diagnoses and deliver treatment. It became apparent later on that telling stories is as powerful as listening to them. Through storytelling, you communicate with a wider audience outside your clinic room. Telling these stories generates empathy, creates understanding, and hopefully inspires the next generation to pursue careers as doctors, psychologists, and healthcare professionals, fostering a fascination with the brain similar to what Oliver Sacks did for me.
THE CREATIVE PROCESS
You talk about these extraordinary things that some people experience, like sleepwalking, where the body is awake but the mind isn't. They don’t remember it afterward. It makes us question free will. We think we’re making decisions, but how awake are we? Are we being manipulated by social media and AI to have more extreme reactions? We like to believe we’re reasonable animals in control, yet we can easily be influenced, like birds flocking together. Social media and AI use neuroscience to create these realities. But there are also many positive aspects; that’s just the dark side.
LESCHZINER
To consider that we don’t have free will in everything we do runs counter to our own experience. It’s a distressing idea that we lack free will in any decision. However, there are influences on our decisions and actions that are beyond our control.
THE CREATIVE PROCESS
So, what are your reflections on AI, the changing political landscape driven by algorithms, and how it affects us neurologically?
LESCHZINER
Society is undoubtedly becoming more polarized. Historically, nation-states were held together by a common narrative. For example, during World War II, there was a unifying narrative that shaped how citizens saw themselves. Social media has disrupted that common narrative, leading to various narratives that individuals select to match their worldview. This divergence of perspectives partly explains our increased polarization. It creates an environment where our views are constantly reinforced by the social media we consume. In The Man Who Tasted Words, I discuss how our realities differ based on our experiences, genetics, knowledge, and culture. It’s crucial to remember that everyone's perspective is unique, yet social media expands those differences.
THE CREATIVE PROCESS
As you think about the future, what lessons have been important for you as you reflect on the kind of world we’re leaving for the next generation? What would you like young people to know, preserve, and remember?
LESCHZINER
It’s easy to be pessimistic about the future. However, if we look at the world in general—at the number of individuals leading easier lives, having better access to food and medicine, enjoying a cleaner environment and clean water—those improvements have been continuous over the years. Overall, humanity is leading better lives than even in the last generation. I think about my children and how they inhabit a slightly kinder world in some respects. Yes, there are issues, but it is a world where people are generally kinder, and behaviors that were once acceptable are now not tolerated. In the developing world, many countries have improved dramatically compared to when we were growing up. The key thing is to maintain hope and avoid pessimism about the future, as that kind of negativity can become a self-fulfilling prophecy.
