#81: Theodore Schwartz - Gray Matters: brain surgery from the inside, the history and the future of neurosurgery

Theodore H. Schwartz is a neurosurgeon, author, and the David and Ursel Barnes Endowed Professor of Minimally Invasive Neurosurgery at Weill Cornell Medical Center and New York-Presbyterian Hospital.In this episode of Stimulating Brains, we talk about his book Gray Matters: A Biography of Brain Surgery, a vivid account of what brain surgery really is – personally, technically, historically, psychologically, and morally.We discuss what it actually feels like to be a neurosurgeon: the preparation before a difficult case, the pressure of thousands of micro-decisions, the responsibility for movement, language, memory, and personhood, and the question of when to enter the brain further and when to stop.We also talk about Ted's path from music and astrophysics toward neurosurgery, the culture of surgical training, trauma and gunshot wounds, the history of pioneers such as Cushing, Penfield, Dandy and others, as well as modern brain surgery, pituitary and skull-base surgery, awake mapping, aneurysms, epilepsy, psychosurgery and deep brain stimulation. We even wander toward consciousness, free will, brain-computer interfaces, and the future of less invasive and more computational neurosurgery.At the center of these more philosophical questions lies a deceptively simple question: what can brain surgery teach us about the brain, the self, and the stories we use to understand who we are?

In this episode of Stimulating Brains, I am delighted to welcome back Michael Okun, neurologist, movement-disorders specialist, Adelaide Lackner Distinguished Professor of Neurology at the University of Florida, Director of the Norman Fixel Institute for Neurological Diseases, and National Medical Advisor of the Parkinson's Foundation.Mike was previously on the podcast in episode 25 together with Kelly Foote. This time, we focus on his new book with Ray Dorsey, The Parkinson's Plan: A New Path to Prevention and Treatment.The book argues that Parkinson's disease should not only be treated after diagnosis, but also understood as a public-health challenge that demands prevention, better care models, patient advocacy, and policy. We talk about the PLAN framework: Prevent the disease, Learn why it begins, Amplify the voices of people affected, and Navigate the frontiers of treatment.We discuss environmental risk factors such as pesticides, solvents, dry-cleaning chemicals, air pollution, and paraquat; the idea that "prevention is not a pill, it is policy"; the Parkinson's 25 and the 0-10-100 by 2035 goal.We also talk about what a real care plan should look like for people living with Parkinson's today, including movement-disorder care, rehabilitation, mental health, caregiver support, exercise, speech and swallow therapy, sensors, and access to multidisciplinary teams.Since this is Stimulating Brains, we also return to deep brain stimulation and neuromodulation: where DBS fits into the broader Parkinson's Plan, what circuit-based therapies may still teach us, and how future treatments might connect prevention, biology, devices, genetics, and care.

Karl Friston is one of the most influential neuroscientists of our time and a central figure in the history of human brain mapping. Many listeners will know him for the free energy principle, active inference, dynamic causal modeling, voxel-based morphometry, and many other theoretical contributions.In this episode, we take a different route and go back to the early history of Statistical Parametric Mapping, or SPM: the software and statistical framework that helped turn functional neuroimaging from a local craft into a shared scientific language.We discuss how Karl moved from psychiatry into brain imaging, what the first PET activation experiments felt like, how SPM emerged at the MRC Cyclotron Unit and later the Functional Imaging Laboratory, how the software spread through the neuroimaging community, and how key collaborators helped shape modern PET, fMRI, VBM, DCM, EEG, and MEG analysis.We also talk about mentorship, the culture of the FIL, open software, MNI space, spatial normalization, and what it means for a scientific tool to become infrastructure for an entire field.

In this episode of Stimulating Brains, I speak with Keith R. Mullett, who can uniquely tell a part of the DBS history that is often skipped.We often begin the story of modern DBS in Grenoble around 1987, when Alim-Louis Benabid and colleagues showed that high-frequency VIM stimulation could suppress tremor. Keith reminds us that Medtronic's first DBS system had already been implanted in 1969, not for tremor or Parkinson's disease, but for severe chronic pain. Keith joined Medtronic in May 1972 and spent 37 years there, first in Minneapolis and later at the Bakken Research Center in Maastricht, where he arrived shortly after Frans Gielen.The conversation goes back before the Benabid era, into the period when Medtronic and its physician collaborators built the devices, surgical know-how, clinical relationships, and regulatory experience that later made DBS for movement disorders possible. We discuss Yoshio Hosobuchi and the first pain implants, RF systems with belt-worn transmitters, the transition from cardiac pacing to neurostimulation, the FDA call for data, ITREL, the Bakken Research Center, and the 1992 tremor study: the moment Keith describes as "the rest is history."This episode also connects to our recent conversations with Todd Langevin (episode 46) and Frans Gielen (episode 75). Todd described the internal venturing and business side of DBS after Benabid, while Frans described the engineering, clinical studies, training, imaging, and new indications that followed. Keith, who was Frans' boss, helps us ask what had to exist inside Medtronic before those later teams could build the modern field.

In this episode of Stimulating Brains, I’m honored to speak with Mary Elizabeth Sutherland, a Deputy Editor at Nature whose areas of responsibility include cognitive neuroscience and a broad range of the behavioural and social sciences. If you work with clinical or human neuroscientific data in the field of brain stimulation and choose to submit to Nature, chances are high that Mary Elizabeth will handle your work.Before moving into scientific publishing, she studied at Cornell, completed her PhD at McGill, and did postdoctoral work in Santiago, Chile. Her own research background includes auditory cognitive neuroscience and music cognition. I’m especially looking forward to talking with her about what the job of a Nature editor actually looks like, how editorial decisions are made in a journal with limited space and broad ambition, how human studies are evaluated in that setting, and where scientific publishing may be heading next.The conversation moves through career paths into editorial work, the day-to-day work of a Nature editor, how scientists become professional editors, and the bar for publishing in Nature, with an emphasis on the choices, constraints, and judgments that shape Mary Elizabeth Sutherland's work.

In this episode of Stimulating Brains, we are honored to sit down with György Buzsáki, Professor of Neuroscience at New York University and one of the most influential thinkers in modern neuroscience.Dr. Buzsaki trained as a physician in Hungary, completed his PhD in neuroscience at the Hungarian Academy of Sciences, and went on to postdoctoral training in North America before building a decades-long academic career spanning UC San Diego, Rutgers University, and now NYU.In this conversation, we explore the ideas behind his work on hippocampal oscillations, sharp-wave ripples, and the organization of neural activity across states such as sleep and wakefulness. Dr. Buzsáki reflects on how his early life experiences, technological innovation, and persistent questioning of dominant frameworks shaped a scientific philosophy centered on internal dynamics rather than task-based explanations.Tune in for a rare opportunity to hear one of neuroscience’s most original voices reflect on the past, present, and future of understanding the brain.

In today’s episode of Stimulating Brains, we have the pleasure of speaking with Frans Gielen — a physicist and biomedical engineer who played a foundational role in shaping modern deep brain stimulation. Over more than three decades at Medtronic, Frans worked at the intersection of engineering, neurology, and surgery during the formative years of DBS, when stereotactic imaging protocols, targeting strategies, and surgical workflows were still being defined in real time.He supported and trained teams in more than 2,000 DBS implantations worldwide, helping refine operative techniques and imaging standards long before they became routine. Beyond the operating room, Frans designed and managed several of the pivotal clinical trials that ultimately led to CE marks in Europe and FDA approvals in the United States — including landmark studies in VIM DBS for tremor, STN and GPi DBS for Parkinson’s disease, the first controlled trial of DBS for obsessive–compulsive disorder, and later the MORE trial in epilepsy.In this conversation, we explore the practical, technical, and regulatory work required to transform DBS from a promising idea into a reliable, evidence-based therapy — and reflect on what it took to build the foundations that the field stands on today.

In this episode of Stimulating Brains, we sit down with Dr. Ludwig Zrinzo, Professor of Functional Neurosurgery at University College London and Head of the Functional Neurosurgery Unit at Queen Square.Drawing on decades of experience at the forefront of deep brain stimulation, Dr. Zrinzo reflects on the evolution of DBS from awake procedures to image-guided surgery under general anesthesia, emphasizing why precision, verification, and closing the loop are essential for improving patient outcomes.We discuss how his experience shaped a rigorous, data-driven approach to targeting, why imaging quality remains a very critical factor in DBS accuracy, and how systematic post-operative verification transformed clinical practice. Beyond technique, Dr. Zrinzo shares deeply insightful perspectives on patient selection, mentorship, leadership, and the responsibility of building sustainable teams in academic neurosurgery.The conversation also ventures into neuropsychiatric DBS, including OCD, where we examine how stimulation in different targets may have differential effects on behavior, illuminating the brain’s underlying circuitry. Finally, we look into the future of adaptive and closed-loop stimulation, emerging electrode technologies, and the future balance between innovation, scalability, and patient-centered care.Tune in for a thoughtful and wide-ranging conversation on precision, evidence, and humanity in brain stimulation — and on how functional neurosurgery continues to teach us how the brain truly works.

In this episode of Stimulating Brains, we sit down with Dr. Eyal Zadicario, Chief Operating Officer at Insightec, to explore the remarkable evolution of focused ultrasound – from its experimental origins to its transformative role in functional neurosurgery today.Dr. Zadicario shares insights from over two decades at the forefront of innovation, reflecting on the challenges of translating breakthroughs from academia to industry, designing clinician-friendly systems that prioritize the patient experience, and overcoming skepticism toward disruptive technologies.Together, we revisit key milestones – from the first MRgFUS based thalamotomy in 2008 and early applications in breast cancer, to the expanding frontiers of neuromodulation. Looking ahead, we discuss the exciting possibilities of blood brain barrier opening, the acoustic neurosurgical suite, and even brain mapping through focused sound.Tune in for a fascinating conversation on how precision acoustics are reshaping the landscape of brain therapy and beyond.

Today, we had the privilege of speaking with Dr. John Rolston, a leading voice at the intersection of neurosurgery, epilepsy, and brain stimulation.Dr. Rolston is an Associate Professor of Neurosurgery at Harvard Medical School and the Director of Epilepsy Surgery at Brigham and Women’s Hospital. His pioneering work bridges clinical neurosurgery and computational neuroscience, focusing on how electrical stimulation can modulate dysfunctional brain networks to treat epilepsy, movement disorders, and disorders of consciousness.In this episode, we explored the complexities of neuromodulation—what makes stimulation effective, why patient-specific targeting matters, and how brain states influence therapeutic outcomes. Dr. Rolston also shared his lab’s work on traveling waves in the brain and how these insights are transforming seizure localization and surgical decision-making. From closed-loop stimulation to stem cell therapy for Parkinson’s disease, Dr. Rolston walks us through the evolving landscape of functional neurosurgery and its future.