Interoception and the autonomic nervous system
The autonomic nervous system is not simply an automatic control system that runs in the background without the brain's involvement. It is continuously monitored, modeled, and regulated by the brain through a sensory process called interoception — the brain's ongoing reading of the body's internal state. How accurately the brain reads those signals, and how it responds to what it reads, determines the quality of autonomic regulation. When that reading is miscalibrated — when the brain's model of internal body state diverges from actual body state — the regulatory outputs it generates diverge with it. A 2023 editorial framework by Ueno and colleagues in Frontiers in Neuroscience provides the conceptual scaffolding for understanding this bidirectional relationship, and it matters for anyone trying to understand why POTS, ME/CFS, and dysautonomia conditions are not simply hardware failures but involve the entire sensing-and-regulating system.
What Interoception Is and Why It Matters
Interoception is the brain's process of sensing the internal state of the body. It encompasses signals from the cardiovascular system (heart rate, blood pressure, vascular stretch), the respiratory system (lung volume, CO2 levels, diaphragm tension), the gastrointestinal system (gut motility, fullness, chemical environment), the musculoskeletal system (through proprioceptive afferents from joints, tendons, and muscles), the immune system (cytokine signaling that reaches the brain via vagal afferents and the bloodstream), and the skin (temperature, touch, pain). All of these signals are continuously transmitted to the brain through autonomic afferent nerves, spinal pathways, and the bloodstream, and are integrated in specific brain regions — notably the insular cortex, anterior cingulate cortex, and brainstem nuclei — into a moment-to-moment model of the body's current physiological state.
This model is not passive. The brain actively generates predictions about what internal body state should be given current behavioral context and prior history, and compares incoming sensory signals to those predictions. When incoming signals match predictions, the prediction is confirmed and minimal adjustment is required. When they don't match, the brain must update either its prediction or its estimate of the signal's meaning. This predictive processing framework for interoception is the same framework that underlies the miscalibration model of autonomic dysfunction — the brain is not simply measuring body state. It is continuously predicting what body state should be and comparing that prediction to what it senses.
The Bidirectional Loop: Brain to Body, Body to Brain
The critical architectural feature of interoception that the Ueno framework emphasizes is bidirectionality. The autonomic nervous system sends signals upward from the body to the brain — this is the afferent interoceptive pathway. But the brain also sends signals downward through autonomic efferent pathways that modulate body state in response to what it has read. This is not a one-way reporting system. It is a continuous feedback loop: body state is sensed, brain generates regulatory response, regulatory response changes body state, new body state is sensed, loop continues.
The quality of this loop depends on two things: the accuracy of the afferent sensing (how precisely the brain reads body signals) and the accuracy of the efferent response (how precisely the brain's regulatory commands match what the body actually needs). When either is miscalibrated, the loop becomes unstable. The brain may be sending regulatory commands calibrated to a body state that is not the actual current state. The commands produce the wrong response. The body state changes in the wrong direction. The brain senses the new state and generates another miscalibrated response. The loop oscillates rather than converging.
This oscillating, miscalibrated loop is a plausible mechanistic description of what dysautonomia conditions produce. The tachycardia in POTS is not simply a heart that is beating too fast — it is the heart responding to a regulatory command that was calibrated to an incorrect model of body state. The command was generated by a brain that assessed orthostatic hemodynamic stress as requiring more heart rate compensation than the physiology actually needed, or that failed to accurately read the baroreflex signals that would normally calibrate the response downward. The tachycardia is the compensatory output of a regulatory loop that is not converging accurately.
Interoceptive Accuracy and Its Consequences for Regulation
Interoceptive accuracy — how precisely a person can sense specific internal body signals — varies across individuals and across conditions. People with high interoceptive accuracy are better at detecting heartbeats, estimating physiological states, and correlating their internal sense of body state with what objective measurement reveals. People with lower interoceptive accuracy have a looser relationship between their subjective body model and actual physiological state.
In autonomic dysfunction, interoceptive accuracy is likely altered in ways that are condition-specific. Some dysautonomia patients appear to be hyperinteroceptive in specific domains — acutely sensitive to heartbeat, respiratory changes, or gut sensations that most people do not consciously detect. Others show disconnects between subjective experience and objective measurement, reporting severe symptoms at physiological values that would not be expected to produce them in an accurately calibrated system. Both patterns are consistent with a miscalibrated interoceptive loop that is not accurately tracking or predicting body state.
In ME/CFS specifically, the Owens research on predictive processing and interoceptive inference establishes that the condition involves systematic over-prediction of physiological cost — the brain is generating threat responses to body signals that would not trigger threat responses in healthy individuals. This is an interoceptive calibration problem: the system is using the wrong priors, generating the wrong predictions, and producing regulatory responses calibrated to predicted threats that are larger than actual threats. The fatigue, the pain amplification, the post-exertional malaise, are all outputs of this miscalibrated predictive loop.
The Autonomic System as a Regulatory Output, Not a Standalone Organ
The practical implication of the interoception framework for understanding dysautonomia is a shift in how the problem is located. Standard clinical framing of autonomic dysfunction asks: what is wrong with the autonomic nervous system? The interoception framework reframes this as: how is the brain modeling and regulating body state, and where in that process is the calibration off?
These are different questions with different therapeutic implications. Treating the autonomic output — suppressing tachycardia with beta-blockers, expanding volume with fludrocortisone — addresses the regulatory command without addressing the sensing and modeling process that generated it. In some patients, treating the output is sufficient to restore functional capacity while the upstream calibration corrects itself. In others — particularly those with persistent miscalibration from chronic sensory processing disruption, proprioceptive degradation from lax connective tissue, or sustained elevation of threat-prediction signals from chronic illness experience — the calibration problem is not self-correcting and needs to be addressed directly.
This is why the social environment matters physiologically: perceived threat from clinical dismissal and disbelief activates the same interoceptive threat-prediction system that generates autonomic stress responses. Reducing that perceived threat — through accurate illness framing, credible clinical communication, and supportive social environment — is reducing an input to the interoceptive loop that is driving miscalibrated regulatory output. It is not a soft intervention. It is modifying a quantifiable input to a regulatory system whose miscalibration is the problem.
A Conceptual Framework, Not a Diagnosis
The Ueno 2023 paper is an editorial introduction to a research collection, not a clinical study. It does not provide specific findings about specific patient populations. What it provides is the conceptual framework for understanding how interoception connects brain and autonomic function — the architectural description of the sensing-modeling-regulating loop that conditions like POTS, ME/CFS, and hEDS are disrupting at various points.
For readers new to this framework, this paper is a conceptual entry point. Understanding that the autonomic nervous system operates within a brain-governed interoceptive loop — that it is not simply an automatic machine that either works or breaks, but a regulatory system that is continuously calibrated by a brain that may or may not be reading body state accurately — changes how the conditions on this site make sense. They are not conditions in which the body is simply malfunctioning. They are conditions in which the sensing, modeling, and regulation of body state has become miscalibrated. That framing opens different therapeutic directions than the purely peripheral hardware failure model, and it grounds the importance of the brain's involvement in dysautonomia at a level that the orthostatic and perfusion research alone does not capture.