Key People

Barrett, Lisa Feldman — American neuroscientist and psychologist at Northeastern University, with appointments at Harvard Medical School and Massachusetts General Hospital, best known for developing the theory of constructed emotion and for her application of predictive processing to affective experience, elaborated in How Emotions Are Made: The Secret Life of the Brain (2017) and the more accessible Seven and a Half Lessons About the Brain (2020). Her central argument overturns the classical view that emotions are universal, biologically hardwired responses with distinct neural circuits and readable facial signatures — what she calls the "classical view" — replacing it with the claim that emotions are actively constructed by a predictive brain that continuously generates best-guess interpretations of incoming interoceptive signals (the body's internal state reports) in light of prior experience, learned conceptual categories, and current context, meaning that what we call "fear" or "anger" is not a discrete biological event triggered by the world but a construction the brain assembles to make meaning of ambiguous bodily sensation. Her work carries significant practical implications: because emotional experience is concept-dependent, a richer emotional vocabulary — what she terms "emotional granularity" — produces finer-grained emotional constructions and is associated with better affect regulation, psychological resilience, and physical health outcomes, positioning the deliberate expansion of one's emotional conceptual repertoire as a concrete lever for wellbeing.

Bergson, Henri — French philosopher (1859–1941), Nobel Prize in Literature, 1927. Proposed what is now called the "transmission theory" of consciousness: the brain does not generate consciousness but filters and channels it from a broader field, restricting awareness to what is relevant for action and survival. Aldous Huxley adapted this framework directly in The Doors of Perception.

Christoff Hadjiilieva, Kalina — Cognitive neuroscientist whose research focuses on spontaneous thought: mind-wandering, daydreaming, creative thinking, and flow states. She edited The Oxford Handbook of Spontaneous Thought. Her research using fMRI with experienced meditators (10,000+ hours of practice) examined the transition of material from the unconscious to conscious awareness. By tracking hippocampal activity, associated with memory and spontaneous thought, she found that neural activity associated with an incoming thought precedes conscious awareness of that thought by approximately four seconds. She interprets this as evidence that thoughts undergo a slow, competitive selection process before reaching awareness. Her broader argument: spontaneous thought is a primary site of creativity that modern technological distraction is systematically eliminating.

Crick, Francis — British molecular biologist who, with James Watson and using Rosalind Franklin's X-ray crystallography data, determined the double-helix structure of DNA in 1953 (Nobel Prize 1962). In the late 1980s, he turned to consciousness science, proposing that the methods of reductive biology could identify the neural correlates of consciousness, the specific brain structures or processes responsible for subjective experience. His program found suggestive correlations but could not bridge the explanatory gap from neural activity to felt experience.

Damasio, Antonio — Portuguese-American neuroscientist at the University of Southern California. Author of Descartes' Error (1994), among other works. His central contribution: feelings and emotions are not peripheral noise in the cognitive system but are constitutive of good decision-making. He demonstrated, through studies of patients with damage to emotion-processing brain regions (particularly the ventromedial prefrontal cortex), that the inability to experience emotion produces systematically worse decisions, disproving the Enlightenment assumption that rationality is best achieved by suppressing feeling. His deeper argument: the brain exists to keep the body alive, not the other way around, and feelings are how the body communicates its states to the brain.

Descartes, René — 17th-century French philosopher and mathematician. He proposed a strict dualism between mind (res cogitans) and matter (res extensa), holding that only humans possess rational souls and therefore genuine consciousness. Animals, in his view, were complex automata; their behaviors, including apparent expressions of pain, were purely mechanical. This position was used to justify vivisection of conscious animals without anesthesia. His most famous philosophical proposition, cogito ergo sum ("I think, therefore I am"), placed human consciousness at the center of epistemology while simultaneously evacuating consciousness from the rest of nature.

Frank, Adam; Gleiser, Marcelo; and Thompson, Evan — Authors of The Blind Spot: Why Science Cannot Ignore Human Experience (2024). Their argument: the physical sciences have a structural blind spot; they are products of human consciousness and cannot step outside it to achieve a purely objective view. The dismissal of qualia as "mere" constructions of the brain (e.g., treating the experience of redness as an illusion while treating the wavelength as real) is an unjustified methodological choice, not a neutral finding. A mature science of nature must find a way to include lived experience as a datum, not bracket it out.

Gopnik, Alison — Developmental psychologist at UC Berkeley. She draws a fundamental distinction between two modes of consciousness. "Lantern consciousness," characteristic of young children, is a diffuse, 360-degree, undirected awareness that takes in information from all directions without filtering or hierarchizing it. "Spotlight consciousness," characteristic of adults, is the narrowed, goal-directed, filtered attention that blocks out peripheral information to concentrate resources on a task. She calls the extreme adult form "professor consciousness." Her research shows that lantern consciousness, though it appears undisciplined, enables more divergent thinking and allows children to solve problems adults cannot. She has noted that LSD produces something resembling lantern consciousness in adults: having tried it herself in her sixties, she recognized it as the state children inhabit continuously.

Grof, Stanislav — Czech psychiatrist and one of the founders of transpersonal psychology. Conducted pioneering research in the 1960s and 1970s on LSD-assisted psychotherapy, including work with terminally ill cancer patients to reduce existential fear and death anxiety. His research documented systematic categories of psychedelic experience and forms the foundation for much current psilocybin-assisted therapy research on end-of-life distress.

Halifax, Joan — American Zen teacher and Buddhist chaplain. Founder and abbess of Upaya Zen Center in Santa Fe, New Mexico. Trained in medical anthropology; has worked extensively with the dying. Formerly married to Stanislav Grof and participated in early psychedelic-assisted therapy research administering LSD to terminally ill patients in the 1970s. Her Zen teaching style, characterized by resistance to conceptual discussion, embodies the don't-know mind — the cultivation of open, non-grasping awareness as a practice in itself.

Hurlburt, Russell T. — Psychologist at the University of Nevada, Las Vegas. Creator of the Descriptive Experience Sampling (DES) method, developed in 1973. Subjects wear a beeper that emits a sharp, unambiguous tone at random intervals throughout the day. At each beep, they record the precise character of their mental activity at that exact moment, not what they were thinking about generally, but what was happening in their mind in the instant before the tone. After each day's beeps, subjects undergo a detailed debriefing in which Hurlburt interrogates the reports to help them become more accurate observers of their own minds. After fifty years of data collection, his key finding is that only about one-third of people think primarily in words; another third think primarily in images; and a significant portion experience what he calls "unsymbolized thought" — inner experience with no verbal or visual medium at all. He has deliberately declined to draw theoretical conclusions from his data.

Huxley, Aldous — British novelist and essayist. In The Doors of Perception (1954), he proposed that the brain functions as a "reducing valve": evolution shaped it to filter out most available consciousness, admitting only the narrow trickle of experience needed for survival and productive functioning. His term "mind at large" refers to the broader field of consciousness that is normally suppressed by this filter. He proposed that psychedelics (he wrote specifically about mescaline) open the valve, flooding awareness with suppressed perceptual and conscious material. He drew this transmission theory of consciousness from the philosopher Henri Bergson.

Jackson, Frank — Australian philosopher. Creator of the Mary's Room thought experiment (1982). Mary is a scientist who possesses all physical knowledge about color vision (neuroscience, optics, the physics of wavelengths) but has lived her entire life in a completely black-and-white environment. When she finally sees red for the first time, she appears to learn something new — something not contained in all her prior physical knowledge. Jackson used this to argue that physicalism is incomplete: there are facts about subjective experience (qualia) that no amount of third-person physical knowledge can capture. The thought experiment has been extensively debated, and Jackson himself later recanted his original conclusion, though it continues to be widely used to frame the explanatory gap.

James, William — 19th-century American psychologist and philosopher, widely considered the father of American psychology, though his approach now reads more as philosophy than empirical science. He functioned as a phenomenologist, attending to the structure and texture of mental experience as it is actually lived, rather than reducing it to measurable correlates. His 1890 essay "The Stream of Consciousness" (from The Principles of Psychology) remains one of the most precise accounts of thought ever written. He argued that thought is not a sequence of discrete units but a continuous, dynamic flow, a stream, in which each moment is colored by what preceded it and shapes what follows. He developed an unusually rich vocabulary for the penumbra surrounding formed thought: "auras," "halos," "accentuations," "associations," "suffusions," "feelings of tendency," "premonitions," "psychic overtones," and "the fringe of unarticulated affinities." He also wrote The Varieties of Religious Experience, which includes a systematic account of mystical states across traditions and documents his own experiments with nitrous oxide to probe the outer reaches of consciousness.

Kabat-Zinn, Jon — American professor emeritus of medicine at the University of Massachusetts Medical School and founder of the Stress Reduction Clinic there, best known for developing Mindfulness-Based Stress Reduction (MBSR) in 1979 — a structured eight-week clinical program that adapted secular mindfulness meditation practices drawn primarily from Theravada Buddhist tradition for use in mainstream medical and psychological settings, described in his foundational works Full Catastrophe Living (1990) and Wherever You Go, There You Are (1994). His central contribution is the operationalization of mindfulness — defined in his now widely cited formulation as "paying attention in a particular way: on purpose, in the present moment, and nonjudgmentally" — into a reproducible, clinically testable intervention, which opened the practice to rigorous empirical investigation and generated decades of research demonstrating its efficacy in reducing chronic pain, anxiety, depression relapse, and stress-related illness, while establishing mindfulness as a legitimate object of scientific inquiry rather than a purely spiritual or contemplative concern. His work forms the foundation of the modern secular mindfulness movement and has directly influenced the development of Mindfulness-Based Cognitive Therapy (MBCT), Dialectical Behavior Therapy (DBT), and Acceptance and Commitment Therapy (ACT), as well as the broader integration of contemplative practice into medicine, psychology, education, and organizational life.

Koch, Christof — German-American neuroscientist, former president and chief scientist of the Allen Institute for Brain Science in Seattle. One of the founders, alongside Francis Crick, of the modern scientific program to identify the neural correlates of consciousness in the late 1980s and early 1990s. Over decades, he substantially changed his views from confident reductive materialism to a serious engagement with panpsychism and, after ayahuasca experiences in Brazil, with idealism. He invokes the Mary's Room thought experiment to explain why a pharmacological explanation of his psychedelic experience does not fully account for what he felt he learned: the experience had epistemic weight that a third-person causal account cannot dissolve.

Leary, Timothy — American psychologist and psychedelic researcher (1920–1996). His lasting scientific contribution is the concept of "set and setting": the content, emotional tone, and interpretive frame of a psychedelic experience are profoundly shaped by the subject's mental state going in (set) and the physical and social environment in which the experience occurs (setting). This framework is now standard in clinical psychedelic research protocols.

Levin, Michael — American developmental and synthetic biologist at Tufts University, where he directs the Allen Discovery Center, whose research focuses on the bioelectric and cognitive properties of living systems at scales ranging from individual cells to whole organisms, with major works and findings published across journals including Trends in Cognitive Sciences, Physics of Life Reviews, and Biosystems. His central and most provocative contribution is the argument that cognition, memory, and goal-directed behavior are not properties unique to neural systems but are fundamental features of life itself: ordinary cells, tissues, and organs process information, store memories, pursue goals, and solve problems through bioelectric signaling — the same electrochemical currency used by neurons, only more slowly — which means that the capacity for something like primitive awareness or agency may be far more ancient and widespread in nature than neuron-centric accounts of mind allow.

Levine, Peter A. — American psychologist and biophysicist, best known as the developer of Somatic Experiencing (SE), a body-oriented therapeutic approach to trauma described in his foundational work Waking the Tiger: Healing Trauma (1997) and elaborated in In an Unspoken Voice: How the Body Releases Trauma and Restores Goodness (2010). His central argument is that trauma is not primarily a psychological or cognitive event but a physiological one: when an organism is overwhelmed by threat and cannot complete the defensive motor responses — fight, flight, or freeze — that the nervous system has mobilized, the incomplete discharge becomes stored in the body as chronic activation, producing the symptoms of post-traumatic stress.

Mancuso, Stefano — Italian plant neurobiologist at the University of Florence and a leading figure in the field of plant intelligence research. His experiments have shown that standard anesthetics used in human medicine, including xenon gas, which is chemically inert and works through a mechanism not fully understood even in humans, suppress the responsiveness of plants for a defined period, after which they recover normal function. He interprets this as evidence that plants have at least two distinct states of being (responsive and non-responsive) analogous to waking and sleeping. He has also demonstrated that plants sleep by Tononi's criteria and that they possess approximately twenty distinct sensory capacities, including sensitivity to pH, sound, electrical signals, and gravity. His ethical position: pain requires the ability to respond by moving away from a threat; since plants are sessile, pain would not be adaptive, and plant awareness of damage is likely not accompanied by suffering.

Nagel, Thomas — American philosopher, best known for his 1974 essay "What Is It Like to Be a Bat?" published in The Philosophical Review. The essay argues that consciousness is essentially subjective: for any conscious entity, there is something it is like to be that entity, a felt, first-person quality of experience. His test for consciousness: if there is something it is like to be a creature, that creature is conscious. If there is nothing it is like to be a thing (a thermostat, a toaster), it is not conscious. The bat is a deliberate choice; bats navigate by echolocation, a sensory modality so different from our own that we cannot imaginatively inhabit it, which is precisely Nagel's point: subjective experience is irreducibly first-personal and cannot be fully captured by any third-person, objective account.

Ogden, Pat — American psychologist and founder of Sensorimotor Psychotherapy, a body-centered therapeutic modality that integrates somatic awareness, movement, and sensation into the treatment of trauma and attachment disorders, described in her foundational texts Trauma and the Body (2006) and Sensorimotor Psychotherapy: Interventions for Trauma and Attachment (2015), co-authored with Janina Fisher. Her central contribution is the recognition that trauma is encoded not only in memory and emotion but in the body's habitual postures, gestures, movement patterns, and physical tensions — what she calls "body memory" — and that lasting therapeutic change requires working directly with these somatic patterns rather than relying exclusively on verbal or cognitive processing.

Porges, Stephen W. — American neuroscientist and professor in the Department of Psychiatry at the University of North Carolina at Chapel Hill and Distinguished University Scientist at Indiana University, best known for developing Polyvagal Theory in 1994, a neurophysiological framework that reinterprets the autonomic nervous system's role in social behavior, emotional regulation, and trauma response, elaborated in The Polyvagal Theory: Neurophysiological Foundations of Emotions, Attachment, Communication, and Self-Regulation (2011) and made more accessible in The Pocket Guide to the Polyvagal Theory (2017). His central contribution is the argument that the autonomic nervous system is not a simple two-branch system (sympathetic activation versus parasympathetic rest) but a three-tiered hierarchy of evolutionary responses: the most primitive is an immobilization or shutdown response (dorsal vagal), inherited from ancient vertebrates and activated under life threat; the intermediate is the sympathetic fight-or-flight response; and the most evolutionarily recent is the social engagement system (ventral vagal), a uniquely mammalian circuit linking the myelinated vagus nerve to the muscles of the face, voice, and middle ear that, when active, produces the physiological conditions for felt safety, social connection, and emotional co-regulation. His theory has been widely influential in trauma treatment, proposing that the therapeutic restoration of felt safety — achieved through prosodic voice, facial expressivity, and attuned relational presence rather than primarily through cognitive intervention — is the necessary precondition for the nervous system to exit defensive states and become capable of the higher-order processing, learning, and relational engagement that healing requires.

Schore, Allan N. — American psychologist and researcher on the faculty of the UCLA David Geffen School of Medicine, widely regarded as one of the leading theorists of the neurobiological underpinnings of emotional development, attachment, and trauma, best known for his dense and extensively referenced trilogy Affect Regulation and the Origin of the Self (1994), Affect Dysregulation and Disorders of the Self (2003), and Affect Regulation and the Repair of the Self (2003), as well as the more accessible The Science of the Art of Psychotherapy (2012). His central contribution is a detailed neurobiological account of how early attachment relationships — specifically the attuned, face-to-face, affectively charged interactions between caregiver and infant in the first two years of life — literally shape the structural development of the right hemisphere of the brain, which he identifies as the neurological substrate of implicit, bodily, and emotional processing, unconscious self-regulation, and the capacity for empathic connection; when early attachment is disrupted or traumatic, this right-hemispheric development is compromised in ways that manifest across the lifespan as difficulties in affect regulation, relational attunement, and resilience.

Seth, Anil — British neuroscientist at the University of Sussex. Author of Being You (2021). He proposes that conscious experience is a form of "controlled hallucination": the brain does not passively receive reality but actively generates its best-guess model of the world based on prior expectations and incoming sensory data. What we experience as reality is a prediction, not a readout. He treats the self as a perception, a construction the brain makes about its own body and agency, rather than a fixed metaphysical entity. His TED talk on consciousness as controlled hallucination is among the most widely viewed in the series.

Siegel, Daniel J. — American clinical professor of psychiatry at the UCLA School of Medicine and executive director of the Mindsight Institute, best known for developing the concept of interpersonal neurobiology (IPNB), an interdisciplinary framework that synthesizes findings from neuroscience, attachment theory, complexity theory, and contemplative practice to describe how the mind, brain, and relationships mutually shape one another, elaborated across numerous works including The Developing Mind (1999), Mindsight (2010), and The Whole-Brain Child (2011). His central contribution is the argument that the mind is not confined to the brain or the skull but is a relational and embodied process — an emergent property of both neurological activity and the flow of energy and information between people — and that mental health is best understood as the flexible, adaptive integration of differentiated systems, whether within the brain itself (linking cortical and subcortical regions, left and right hemispheres) or between individuals in relationship. He developed the clinical concept of mindsight, the capacity to perceive and work with the internal states of oneself and others.

Solms, Mark — South African neuropsychologist and psychoanalyst at the University of Cape Town, a fellow of the Royal College of Psychiatrists, and one of the leading figures in the field of neuropsychoanalysis — an interdisciplinary project that seeks to ground psychoanalytic concepts in contemporary neuroscience — best known for The Brain and the Inner World (2002, with Oliver Turnbull) and The Hidden Spring: A Return to the Source of Consciousness (2021). He argues, against the dominant assumption that consciousness originates in the cerebral cortex, that it arises first in the upper brainstem, with primordial feelings (hunger, pain, itch, temperature) as its earliest and most basic form. This makes consciousness inherently embodied and affective from the start, with sophisticated cortical cognition as a later elaboration. He also proposes that "consciousness is felt uncertainty": it arises specifically when automated processes cannot resolve competing needs or novel contingencies, opening a deliberative space. A fully predictable world would have no need for consciousness.

Taft, Michael — Meditation teacher whose guided sessions are widely available on YouTube. His approach emphasizes non-engagement rather than control: rather than attempting to suppress or direct thought, simply let the machinery of the mind run without following it, put it down the way you might put down a phone.

Tononi, Giulio — Italian-American neuroscientist and psychiatrist at the University of Wisconsin-Madison, where he directs the Wisconsin Institute for Sleep and Consciousness, best known for developing Integrated Information Theory (IIT), one of the most mathematically rigorous and philosophically ambitious formal theories of consciousness currently under active scientific investigation, elaborated across a series of papers and in accessible form in Phi: A Voyage from the Brain to the Soul (2012). His central contribution is the proposal that consciousness is identical to integrated information — measured by a quantity he designates phi (Φ) — defined as the amount of information generated by a system as a whole above and beyond the information generated by its parts independently, such that a system is conscious to precisely the degree that its internal causal structure is irreducible: a claim with the striking implication that consciousness is not an emergent byproduct of neural complexity but a fundamental feature of any system with sufficiently high phi, potentially including simple organisms and, in principle, non-biological systems, while excluding systems like feedforward neural networks that process information without true internal integration.

Turkle, Sherry — American sociologist and clinical psychologist at MIT, where she is the Abby Rockefeller Mauzé Professor of the Social Studies of Science and Technology and founder of the MIT Initiative on Technology and Self, best known for a trilogy of works tracking the psychological and relational consequences of digital technology across four decades: The Second Self: Computers and the Human Spirit (1984), Life on the Screen: Identity in the Age of the Internet (1995), and Alone Together: Why We Expect More from Technology and Less from Each Other (2011), followed by the more prescriptive Reclaiming Conversation: The Power of Talk in a Digital Age (2015). Her central argument, developed through decades of ethnographic interviews and clinical observation, is that digital technology — and increasingly AI companionship — does not merely augment human connection but subtly substitutes for it, training people to prefer the frictionless, always-available, endlessly validating interactions that machines offer over the effortful, unpredictable, and mutually demanding encounters of genuine human relationship, with the result that capacities for empathy, solitude, and self-reflection — all of which require tolerance of discomfort and uncertainty — are progressively eroded.

van der Kolk, Bessel — Dutch-American psychiatrist and founder of the Trauma Center in Boston, best known for The Body Keeps the Score: Brain, Mind, and Body in the Healing of Trauma (2014), one of the most widely read works on trauma in the clinical and popular literature. His central argument is that traumatic experience is not primarily stored as narrative memory but as sensory and somatic imprints, fragmented images, physical sensations, autonomic arousal patterns, and motor impulses, that persist in the body and nervous system largely outside conscious verbal recall, producing symptoms that standard talk therapy, which operates primarily through language and cognitive reflection, is structurally ill-equipped to resolve.