Your body knew before you did
In the early 1990s, neuroscientist Antonio Damasio ran an experiment that changed how we understand decision-making. Participants played a card game — the Iowa Gambling Task — choosing from four decks. Two decks were rigged to produce large gains but catastrophic losses. Two others produced modest gains with small losses, netting positive over time. Most players needed about 80 cards before they could consciously explain which decks were dangerous. But their skin conductance responses — measurable changes in palm sweat — started spiking before they reached for the bad decks after only 10 cards. Their bodies had identified the pattern 70 cards before their conscious minds caught up.
This is not a metaphor about "trusting your gut." This is empirical evidence that your body processes information your conscious mind has not yet assembled into a narrative. Physical sensations — tension in your shoulders, a knot in your stomach, a sense of ease in your chest — are not noise. They are data. And if you are building an epistemic infrastructure for clear thinking, ignoring an entire data channel is a design flaw.
Somatic markers: the body's tagging system
Damasio named this mechanism the somatic marker hypothesis. The core claim: when you encounter a situation that resembles a past experience, your body generates a feeling — a "marker" — that biases your decision-making before conscious deliberation begins. These markers are processed in the ventromedial prefrontal cortex and the amygdala, brain regions that link emotion, body state, and decision logic into a single circuit.
Think of somatic markers as metadata tags your nervous system attaches to situations. You walk into a meeting room where the last three meetings produced bad outcomes. Before anyone speaks, your chest tightens. That tightness is not irrational — it is your body retrieving a compressed summary of three previous experiences and flagging: pay attention here. The compression is lossy. You cannot decompose the tightness back into the three specific meetings. But the signal is real, and research on patients with ventromedial prefrontal cortex damage shows what happens without it: they can reason about options perfectly well on paper but make catastrophically poor decisions in practice, because they have lost the body's tagging system.
The critical nuance is that somatic markers are not verdicts. They are flags. They bias your attention toward or away from options, narrowing the decision space so your slower, deliberate reasoning has fewer candidates to evaluate. Damasio was explicit about this: the body does not decide for you. It reduces the combinatorial explosion of choice by pre-filtering based on accumulated experience.
Interoception: the skill of reading your own body
Not everyone reads body signals with equal accuracy. The field studying this skill is called interoception — the perception of internal bodily states. Sarah Garfinkel and colleagues at the University of Sussex drew a critical distinction in 2015 between three dimensions: interoceptive accuracy (how well you actually detect signals like your heartbeat), interoceptive sensibility (how well you think you detect them), and interoceptive awareness (how well your confidence tracks your actual accuracy). These three dimensions are dissociable — you can be accurate without knowing it, or confident without being accurate.
This matters because interoceptive accuracy correlates with better decision-making. A 2022 study published in Frontiers in Psychology found that children with higher interoceptive accuracy showed measurable advantages in decision tasks, and the effect holds in adults. People who can accurately count their heartbeats without touching their pulse make better choices under uncertainty — not because the heartbeat itself carries decision-relevant information, but because accurate interoception gives you access to the somatic markers that do.
The practical implication: interoception is trainable. Garfinkel's research demonstrated that eight sessions of interoceptive training improved heartbeat detection accuracy and reduced anxiety symptoms. You can get better at reading your own body, and getting better changes the quality of information available to your decision-making.
Embodied cognition: thinking is not just a brain event
The somatic marker hypothesis is one piece of a larger research program. Embodied cognition — advanced by researchers including Lawrence Barsalou, George Lakoff, and Mark Johnson — argues that cognition is not a purely neural event running on brain hardware. It is shaped by the body's structure, its sensory systems, and its physical interactions with the environment.
Lakoff and Johnson demonstrated that our most basic abstract concepts derive from physical experience. "Understanding" is "grasping." A "weighty" decision carries physical metaphorical load because your body knows what weight feels like. These are not decorative metaphors — they are evidence that the neural circuits handling abstract reasoning reuse the same circuits that handle physical sensation. Gallese and Lakoff argued that knowledge itself is mapped and processed within the sensorimotor system, meaning your body is not just a vehicle that carries your brain around. It is part of the cognitive apparatus.
Barsalou's work on modal symbols reinforces this. When you recall a concept, your brain partially reactivates the sensory and motor states present when you first learned it. Remembering what "sharp" means involves a micro-activation of the neural patterns associated with touching something sharp. This means every concept you hold has a somatic signature — a body-state fingerprint. When something "feels off" about a plan, that feeling may be the partial reactivation of body states from similar situations that went wrong.
Gut feelings: when the body outperforms analysis
Gerd Gigerenzer, director of the Harding Center for Risk Literacy, spent decades studying when simple heuristics — including body-based intuition — outperform complex analytical models. His research shows that in environments with high uncertainty, limited data, and time pressure, the fast-and-frugal strategies that gut feelings embody often produce better outcomes than exhaustive deliberation.
Gigerenzer's signature example: experienced chess players generate the best move first and do not improve with additional deliberation time. Novices benefit from extended analysis; experts do not. The expert's body of experience has been compressed into pattern-recognition circuits that express themselves as feelings — a sense of rightness or wrongness about a position — before the player can articulate the strategic logic.
This maps directly onto professional expertise in any domain. A senior engineer reviews a pull request and feels tension in their jaw before they can name the bug. A seasoned product manager reads a roadmap and feels a heaviness in their chest before they can articulate why the strategy will not hold. These are not mystical phenomena. They are the output of thousands of hours of pattern exposure, compressed by the nervous system into somatic signals that arrive faster than propositional reasoning.
The key insight from Gigerenzer is that gut feelings are not the opposite of intelligence. They are intelligence — unconscious, embodied, experience-weighted intelligence operating through heuristics that evolution refined over millions of years and professional experience refined over thousands of hours.
AI has no body, and that matters
Here is where this lesson connects to the broader landscape of human-AI collaboration. Large language models process text. They identify statistical patterns across billions of tokens. What they do not have is a body — no nervous system, no interoceptive signals, no somatic markers, no embodied history of physical interaction with the world.
This is not a temporary limitation waiting for a hardware upgrade. Researchers studying embodied AI — including work at the Human Brain Project and Meta's Fundamental AI Research lab — argue that human-level cognition may require embodiment as a prerequisite, not an accessory. The somatic marker system works because it evolved inside a body that feels consequences: pain when you touch a hot surface, nausea when you eat spoiled food, tension when social dynamics threaten your standing. An AI that processes the word "danger" has a statistical representation of co-occurring tokens. A human who encounters danger has a full-body state change that alters breathing, muscle tension, hormonal balance, and attentional focus.
This means your body is a cognitive asset that AI cannot replicate. When you use AI to analyze options, generate plans, or evaluate arguments, the AI contributes pattern matching across vast textual corpora. Your body contributes something the AI cannot: a felt sense grounded in your specific history of physical, emotional, and social experience. The optimal workflow is not choosing between analytical AI and somatic intuition. It is triangulating between them — letting AI surface options your conscious mind might miss, while letting your body flag which options feel right or wrong based on experiential data the AI has no access to.
The risk is that over-reliance on AI for decision-making gradually atrophies your interoceptive skill. If you always defer to analytical output and dismiss body signals as "irrational," you are voluntarily shutting down a data channel that has been calibrating itself since before you could speak. The discipline is to keep both channels active: read the AI's analysis and check what your body says. When they diverge, that divergence is itself a signal worth investigating.
Protocol: building somatic data literacy
Step 1 — Establish a baseline. Three times daily for one week, pause and scan five body regions: jaw, shoulders, chest, stomach, and hands. Rate each on a 1-to-5 tension scale. Note what you were doing. This creates a somatic baseline — a map of your body's resting state versus its activated states.
Step 2 — Tag decision moments. Before any non-trivial decision (accepting a meeting, approving a design, responding to a difficult message), pause for 10 seconds. Note the strongest body sensation and its location. Write it alongside your reasoning. Do not act on the sensation — just record it.
Step 3 — Correlate retrospectively. After two weeks, review your log. Look for cases where your body signal predicted an outcome your analysis missed — and cases where it led you astray. You are calibrating your somatic instrument, learning where it is reliable and where it is noisy.
Step 4 — Triangulate. When facing a decision, explicitly gather three data streams: your analytical assessment, your somatic signal, and (when available) AI-generated analysis. Where all three converge, confidence is high. Where they diverge, slow down and investigate the disagreement. The divergence is the most information-rich signal of all.
Your body has been collecting data your whole life
The previous lesson — Notice what you are not seeing — asked you to identify gaps in your perception. This lesson adds a channel you may have been ignoring entirely. Your body has been processing information about every environment you have entered, every person you have interacted with, every decision you have made. That processing leaves traces: tensions, ease, constrictions, openness. Those traces are data.
The next lesson — Suspend the need to be right — will ask you to hold positions loosely, treating them as hypotheses rather than identities. Body awareness makes this easier. When you notice that your jaw clenches every time someone challenges your position, you have a somatic signal that you have fused with a belief. The body reveals attachment that the intellect can rationalize away.
You do not need to become a meditation practitioner or a yoga instructor to use this skill. You need to stop dismissing physical sensation as irrelevant to cognition. Your body carries data. Learn to read it.
Sources:
- Damasio, A. (1994). Descartes' Error: Emotion, Reason, and the Human Brain. New York: Putnam.
- Bechara, A., Damasio, A., Damasio, H., & Anderson, S. (1994). Insensitivity to future consequences following damage to human prefrontal cortex. Cognition, 50(1-3), 7-15.
- Garfinkel, S. N., Seth, A. K., Barrett, A. B., Suzuki, K., & Critchley, H. D. (2015). Knowing your own heart: Distinguishing interoceptive accuracy from interoceptive awareness. Biological Psychology, 104, 65-74.
- Gigerenzer, G. (2007). Gut Feelings: The Intelligence of the Unconscious. New York: Viking.
- Lakoff, G., & Johnson, M. (1999). Philosophy in the Flesh: The Embodied Mind and Its Challenge to Western Thought. New York: Basic Books.
- Barsalou, L. W. (2008). Grounded cognition. Annual Review of Psychology, 59, 617-645.
- Dunn, B. D., Galton, H. C., Morgan, R., Evans, D., Oliver, C., Meyer, M., Cusack, R., Lawrence, A. D., & Dalgleish, T. (2010). Listening to your heart: How interoception shapes emotion experience and intuitive decision making. Psychological Science, 21(12), 1835-1844.