What Is Interoception?
Right now, in this moment, do you know where your body is? Literally. Can you feel your feet on the floor? Your heartbeat? Do you know if you're hungry, or are you just assuming you should eat because it's noon? Do you know if you're tired, or are you running on a vague sense of something being off that you've been quietly ignoring for three hours?
Some of you read that and just got very uncomfortable because you realized you have no idea. Some of you are like, of course I know, I can feel everything, it's overwhelming and I wish I couldn't. And some of you went, huh, that's a weird question, and then kept reading, and I appreciate that. All three of those responses are about the same thing: interoception. The sense you probably were never taught you had, that explains more about how you function than almost anything else.
PART ONE: THE EIGHTH SENSE
You were taught about five senses in school. Sight, hearing, smell, taste, touch. Maybe you got a bonus lesson on proprioception, which is the sense of where your body is in space, like knowing your arm is raised even when your eyes are closed. And maybe, if you were lucky, someone mentioned vestibular sense, which is balance and movement through space. But interoception? Almost nobody learns about interoception in school. And it might be the most important one.
There is an ongoing debate about how to number the senses, and depending on who you ask, humans have anywhere from six to twenty-one of them. Interoception consistently makes the list of the ones researchers consider most fundamental but it never made it into the elementary school curriculum.
Interoception is your brain's ongoing sensory map of the inside of your body. The internal state of the organism you are living in right now. Heart rate. Breathing. Temperature. The stretch and pressure of your gut. Muscle tension. Bladder fullness. Pain. Itch. Nausea. Hunger. The particular flavor of wrong that happens when your blood sugar drops and you haven't noticed yet. It is your body talking to your brain, constantly, on a channel most of us were never taught to tune into.
The neurosceintist Antonio Damasio spent decades making the case that the body is the foundation of the self. The brain is embedded in a body that is sending it information every single second, and that information shapes your mood, your memory, your attention, and the decisions you think you're making with pure logic. Interoception is how that mechanism runs. It is the sensory system that carries the body's state into the brain's awareness, continuously, as the raw material for everything else.
PART TWO: THE NEUROSCIENCE, WITHOUT MAKING IT BORING
Your body has a massive network of sensory receptors embedded in almost every organ and tissue. These are dedicated internal sensors, distinct from the ones that track the external world. They detect mechanical stretch, like when your stomach fills. They detect chemical signals, like changes in blood oxygen or glucose. They detect temperature changes. They detect inflammation. They detect pain. And they send that information up through a dedicated highway.
That highway runs primarily through the vagus nerve, an extraordinary cranial nerve that wanders down from your brainstem, through your neck, into your chest and abdomen, carrying a two-way conversation between brain and body. About eighty percent of the fibers in the vagus nerve run upward, from body to brain. Your brain is mostly listening. It receives far more than it sends. The body has more influence over the brain than most people assume, and the brain's job is largely to make sense of what the body is already doing.
That information lands in the insular cortex, or the insula. The insula is tucked inside a fold of your brain, and it integrates all of that incoming body signal and does a first pass at asking: what does this mean? It is where raw physical sensation starts becoming something we can be aware of. Damage to the insula is associated with difficulty recognizing thirst, difficulty feeling the urge to breathe normally, and profound disruptions to emotional expereince. The insula connects to your anterior cingulate cortex, which handles attention and emotional salience, then to your prefrontal cortex, which handles executive function and decision-making, and then to deeper limbic structures involved in emotion and memory. All of these regions are talking to each other, all the time, building a constantly updated model of what your body's state means for what you should do next.
Neuroscientist Karl Friston theorized predictive processing. He posited the core idea of it is that your brain is a prediction machine. It is constantly generating a model of what it expects to be true, comparing that model to the actual incoming signals, and updating when there is a mismatch. The brain runs a continuous simulation of its own body, and the incoming interoceptive signal is used to correct errors in that simulation. Much of what the brain is predicting, all the time, is the body's state. What is my heart rate going to do? How full is my stomach? Am I hot or cold? What is my energy level? Interoception is the sensory side of that loop. It is the incoming signal that the brain uses to check its body-predictions against reality. When there is a mismatch between what the brain predicted and what the body is actually reporting, the brain has to resolve it. Sometimes it updates the prediction. Sometimes it modifies the body's state to match the prediction. Sometimes, when the signal is unclear or unreliable, it keeps running the old prediction. That is where the downstream problems accumulate.
When the interoceptive signal is clear and consistent, the brain's predictions stay close to reality, it updates efficiently, and it can generate responses that match what's actually happening. When the signal is noisy, muted, delayed, or overwhelming, the predictions drift. And when the body-predictions drift, everything downstream is affected. Emotion regulation. Attention. Decision-making. Energy management. Social behavior. Sense of self.
Everything.
PART THREE: WHAT INTEROCEPTION ACTUALLY DOES FOR YOU
Interoception is how you know you're hungry. It might sound obvious to some of you, some of you can absolutely imagine how many people genuinely do not reliably receive that signal. Many folks don't feel a clear, recognizable hunger signal until you've gone so long without food that you're suddenly crashing, irritable, unable to focus, or nauseated. And you often have no idea interoception is what's missing. You may have been told, or have told yourself, you're just bad at self-care. Interoception is also how you know you're tired. The actual felt sense of fatigue in your muscles and behind your eyes and in your chest, as distinct from the cultural version where you've been told it's time to sleep. A lot of people override this signal for so long and so consistently that you lose access to it. You may run on stimulants, like caffeine, and adrenaline and momentum, and then wonder why you crash so hard. The signal stopped being audible over everything else.
Interoception is a major driver of emotion. What we call emotions are partly body events that the brain interprets. When you notice your heart rate increasing and your chest tightening and your breathing changing, your brain has to decide what that means. Is this fear? Is this excitement? Is this anger? Is this the beginning of a panic attack? The context shapes the interpretation, but the raw material is bodily sensation. Reduced interoceptive access means reduced accuracy in identifying what you're feeling emotionally. You feel something, but it arrives without a label, or with the wrong one.
Interoceptive awareness is correlated with emotional granularity, which is the ability to distinguish between similar emotional states with precision. Not just whether something feels tolerable or overwhelming, but whether what you're experiencing is frustration versus disappointment, or excitement versus anxiety, or grief versus exhaustion. These distinctions matter because they map onto very different responses. Treating anxiety like excitement leads somewhere very different than treating it like dread. The right label isn't semantics,it is the difference between a response that fits the situation and one that compounds it.
Interoception also shapes motivation and reward. When you are in a state of bodily need, whether that's hunger, fatigue, pain, or depletion of some kind, your motivational system is shaped by that signal. Damasio's somatic marker hypothesis argues that bodily states act as markers that bias our decision-making toward options that have historically resolved similar states. Your body has been tracking outcomes for your whole life, associating certain choices with certain physical consequences, and those associations show up as felt inclinations before you've had time to think things through consciously. Clear interoceptive access is how you read those markers. Without it, your decision-making is working without crucial information, and you may find yourself making choices that don't serve you without knowing why. And interoception is foundational to your sense of self. Anil Seth at the University of Sussex argues that the felt sense of being you, of having a continuous, embodied self, is partly constructed from your ongoing interoceptive experience. You feel real, in part, because you feel your body, continuously, as a coherent physical presence in the world. The mechanism is literal: the brain uses interoceptive continuity as one of the anchors for the sense that there is a consistent self having these experiences. When that signal is disrupted, the sense of self can feel disrupted too. This is part of why depersonalization and derealization often involve disrupted interoception.
PART FOUR: INTEROCEPTION IN OCCUPATIONAL THERAPY (OT)
OT is fundamentally concerned with how people participate in the activities that make up their lives, which scopes interoception amazingly well. If you cannot feel when you're tired, you cannot respond appropriately to fatigue. If you cannot feel hunger, mealtimes become disconnected from genuine need. If you cannot accurately read your level of physical discomfort or arousal, self-care and daily functioning require workarounds you probably didn't know you were doing.
Kelly Mahler is an occupational therapist who developed an interoception curriculum specifically designed to help people build awareness of and relationship with their body's signals. Her work emerged from practice with autistic and other ND people, and it has been applied far more broadly, because the need is far more broadly distributed than the clinical literature historically acknowledged. Her central idea is that interoception is a prerequisite for emotional regulation. Before you can regulate an emotion, you have to be able to notice that you're having one. Before you can notice you're having an emotion, you have to be able to feel the bodily state that generates it. With poor interoceptive access, the first signal you might get that something is wrong is behavioral. You've already exploded, or shut down, or fled, before you had any conscious awareness that you were escalating. This is a sensory processing difference. The intervention is to build the sensory access that makes noticing possible in the first place. You cannot regulate what you cannot feel.
Mahler's curriculum works from the ground up. It starts by building body awareness through structured, low-stakes practice. What does running in place feel like? Where do you notice it? Can you describe it? What changes when you stop? It builds an experiential vocabulary. Over time, that vocabulary becomes available for more complex internal states, because the brain has practice attending to and labeling body signals when there is nothing riding on the answer.
The OT framework also recognizes that interoception exists on a spectrum of accuracy and sensitivity. If you are interoceptively hypersensitive, you are receiving a strong, loud internal signal that may be overwhelming, distracting, or difficult to regulate around. The fire alarm is going off all the time and it is hard to do anything else. If you are interoceptively hyposensitive, you are receiving a muted or absent signal and flying blind about your own internal state. Both affect function, through different mechanisms. The same person can be hypersensitive in some domains and hyposensitive in others. You might have a very intense awareness of pain and almost no awareness of hunger. You might feel every fluctuation in your heartbeat but have almost no access to your fatigue signals. Interoception is a collection of different sensory streams, and those streams can have very different levels of clarity and intensity. A global assessment of someone's interoceptive profile misses most of what's actually happening.
PART FIVE: INTEROCEPTION ACROSS NERVOUS SYSTEMS
Every nervous system has its own interoceptive signature. The research on autism and ADHD shows variation in how the system works. The word deficit implies there is one right way to have interoception, and there isn't.
For autistic people, the research has consistently found differences in three distinct dimensions: interoceptive accuracy, which is how closely your body-reading matches what's actually happening; interoceptive sensibility, which is how much you attend to and trust your internal signals; and interoceptive awareness, which is the alignment between your perceived accuracy and your actual accuracy. These three things don't always move together. Someone can have high sensibility, meaning they attend closely to body signals, and still have low accuracy, meaning what they report does not reliably match external measures. Understanding which dimension is where the variation lives matters for what kind of support is actually useful. Some autistic people have very high interoceptive sensibility, meaning they are intensely attending to body signals, but the signal itself may be intense, variable, or difficult to contextualize. The volume is high but the map for making sense of what the volume means is still being drawn. Others have lower sensibility, meaning they have learned, often through years of being told their experience doesn't match what's expected, to suppress or dismiss the signal. Some of this suppression is learned. It is adaptive in environments that don't accommodate the way you process. Adaptive suppression still has a cost: you lose access to information your nervous system was generating.
For people with ADHD, different patterns show up. Attention is regulated at the level of the nervous system, and interoception is itself an attentional process. The insula and anterior cingulate cortex are your interoceptive processing hubs, and they are also heavily involved in attentional regulation. When attention is dysregulated, the ability to sustain focus on slow-moving internal signals is affected too. You might miss hunger because you're hyperfocused on something interesting. You might miss fatigue for the same reason. And then you crash. The signal was present, but the attentional resources to register it were elsewhere.
There is also a phenomenon called interoceptive disconnection that shows up in trauma responses. When the body becomes associated with threat, one adaptive strategy is to dampen the incoming signal. To become less aware of what the body is feeling, because feeling it is dangerous. This is part of the neuroscience of dissociation, and it is important context for why many people with trauma histories have difficulty with interoception. The disconnection served a protective function. The work of reconnecting is slowly building a new relationship with a signal that previously meant danger. Every nervous system interacts with interoceptive processing in its own way, and understanding how yours works creates opportunities for support that actually addresses the mechanism rather than just the symptom.
PART SIX: ALEXITHYMIA AND THE PROBLEM OF NOT HAVING WORDS
Alexithymia is closely connected to interoception and wildly underrecognized.
Alexithymia is a term that comes from the Greek: a, meaning without; lexis, meaning words; thymos, meaning emotion. It describes a pattern in which people have difficulty identifying and describing their own emotional states. They have emotions. They have limited access to those emotions as nameable, describable things. And the research suggests this is strongly connected to interoception. From the inside, alexithymia can feel like a kind of blankness where other people seem to have rich emotional experiences you cannot quite access. Or it can feel like a wall of undifferentiated something, a sense that you are experiencing something significant but cannot pin down what it is. If you experience alexithymia, you might describe knowing intellectually that a situation should produce an emotional response while not being able to feel that response clearly. You may describe an emotional experience in physical terms instead, because the body signal may be available even when the emotional label is not.
The model that most researchers now work with is that emotion identification depends on reading bodily states. When the interoceptive signal is unclear, muted, or difficult to interpret, the downstream process of naming and understanding your emotional state is also impaired. You feel something is wrong but you cannot say what it is. You know you're not fine but you cannot locate why. You get asked how you feel and you genuinely don't know, because you don't have access to the information. Alexithymia is present in a significant proportion of autistic people, and it is increasingly recognized as relevant in ADHD, trauma, and many other contexts. Research by Damian Milton, Rebecca Brewer, and others pulled apart which aspects of autistic experience are attributable to autism itself and which are attributable to co-occurring alexithymia. Some things historically attributed to autism, like reduced emotional response or seeming emotionally flat, may be more specifically related to alexithymia. The distinction matters clinically and personally, because the support that helps with alexithymia is different from the support designed around other aspects of autistic experience.
Alexithymia is trainable. When people develop better interoceptive awareness, their emotional identification often improves. The words become available because the underlying signal becomes clearer. The interoceptive system and the language system have to build new connections, and that takes repeated practice in contexts where the stakes are low enough to pay attention. People who have spent decades without reliable emotional vocabulary can start developing it.
PART SEVEN: PREDICTIVE INTEROCEPTION AND THE BODY BUDGET
Friston's predictive processing framework and Lisa Feldman Barrett's body budget concept come from different directions and land in the same place, which is a good reason to take notice.
Barrett uses the metaphor of a body budget to describe what the brain is doing with interoceptive information. Your brain is constantly forecasting what resources your body will need, allocating them in advance, and then adjusting based on what actually happens. Heartbeats, breath, glucose, immune resources: all of this is being tracked and managed through a predictive loop. The brain is running the books. And like any budget, it can run a surplus, or it can run a deficit. When the body budget is well-managed and the predictions are accurate, you feel reasonably well. When predictions are systematically off, when the brain is consistently over or underestimating what's needed, you feel off in ways that are hard to localize. You're not sick, exactly. You're not in pain, exactly. But something feels wrong. You're tired but can't sleep. You're flat. You're dysregulated and you don't know why. That is a budget deficit from the inside.
Barrett argues that affect, the basic felt sense of valence and arousal that underlies all more specific emotions, is partly a read-out of the body budget. Are things roughly balanced? Are you running a deficit? Is your brain predicting an incoming demand it doesn't have resources for? All of that shapes a felt sense that colors everything you experience. When the budget is stressed, threat feels more likely, effort feels more costly, and the world narrows. When the budget is solvent, the same situations read differently. This is why sleep, food, movement, and social connection have such a measurable effect on mental health. They are the primary inputs that keep the body budget solvent. When any of those inputs is chronically disrupted, the interoceptive signal that the brain is working with is degraded, the predictions drift, and everything downstream reflects that. You cannot think or feel or regulate your way out of a depleted body budget. You have to actually replenish it. It also explains something a lot of people in neuroinclusive communities have known empirically for years: regulation is a lot easier when the basics are covered. This is just budget math.
PART EIGHT: HOW INTEROCEPTION DEVELOPS AND WHAT HAPPENS WHEN IT DOESN'T
Interoception develops over time, and that development depends on both biological maturation and experience.
In early childhood, the body signals are there, but the capacity to interpret them, to attach meaning and language to them, develops through interaction. When a caregiver consistently and accurately responds to a child's bodily states, naming them, validating them, and helping the child learn to associate internal signals with meaning, they are scaffolding the child's interoceptive development. This is sometimes called co-regulation. It is teaching the nervous system to make sense of itself. The child learns it through having their internal states reflected back somewhat accurately by someone who can help read them. When this scaffolding is absent, inconsistent, or misattuned, the child's interoceptive development can be disrupted. The signal is there but there's no map for making sense of it. Sometimes, the child learns that the signal is unreliable because their caregivers' responses didn't match their actual states. Children may also learn to suppress the signal because expressing their internal state led to unpredictable or punishing outcomes. In each case, the child's relationship with their own interoceptive experience is shaped by what happens when they try to communicate it.
Caregivers can only scaffold what they themselves have. A caregiver who is alexithymic, or who is themselves operating from a poorly mapped interoceptive system, cannot accurately mirror what they cannot feel. This is how interoceptive difficulty transmits across generations, through the relational scaffolding that either builds or fails to build the map, not through genetics alone. It is important to understand this as a mechanism rather than a moral failure in some circumstances.
For children whose nervous systems process interoception differently, which includes many autistic and ADHD children, there is an additional layer. Their signals may not match the cues that caregivers have been taught to read. They may have very intense signals in some domains and nearly absent signals in others. A caregiver who doesn't know this may consistently misread or correct the child's self-reports, inadvertently teaching the child that their body-signal is wrong. That is a very hard thing to unlearn, especially when it happens early, consistently, and from people you depend on. If you need support and resources for parenting a neurodivergent kiddo, I offer education and practical strategies.
Interoception is plastic, though. The brain continues to learn to read the body more accurately throughout life. It is slower work in adulthood than in childhood, as most developmental things are. But the capacity does not close. People rebuild interoceptive access after trauma. People develop emotional vocabulary in their forties that they never had in their twenties. The window is long, and the nervous system is responsive to experience for much longer than we used to think.
PART NINE: THE PRACTICAL STUFF
Where does any of this land in real life? Because education that doesn't go somewhere actionable is just trivia (and no hate, I live trivia, but I also love when it becomes applicable). Building interoceptive awareness requires returning attention to the body repeatedly, in ordinary moments, over time. In moments when you have a little space. What does this feel like? Where do I notice it? Can I describe it without immediately judging it? The goal early on is contact, not accuracy. Just staying in enough relationship with the signal to begin building a map.
Body scan practices, which come out of mindfulness traditions and have been adapted in clinical settings, work by systematically directing attention through different regions of the body with the goal of noticing rather than changing. Mahler's OT framework offers structured activities for people who find that open attention to the body is too much, too fast. Starting with movement, with proprioceptive input, with things that generate clear and grounded body signals, builds a foundation that makes more subtle internal awareness possible later. You earn the quieter signals by practicing with the louder ones first.
If you're a clinician or a coach, shifting your client's regulation work toward an interoceptive frame often changes what's accessible to them. The question is what are you noticing in your body right now, rather than how do you feel, which for many people with alexithymia or interoceptive differences is an unanswerable question that tends to produce shame. Slow down. Make space. Don't automatically interpret for them. Let them practice finding the signal. Describe what you observe from the outside, if they give you permission, and offer it as information. Ypu could say, "I notice your breathing has changed. What do you notice?"
I offer consulting services and training to clinicians, coaches, and clinics on interoception.
For people with ADHD specifically, external reminders, body check-ins, and building signals into routines can help compensate for attentional inconsistency. The attentional system is demand-sensitive. It needs the body signal to be brought into competition with whatever else is claiming its attention, and external scaffolds do exactly that. An alarm that says check in with your body makes a real signal audible again.
And for anyone who finds that the body feels like a foreign country, who feels more comfortable in their head than in their skin, who has spent years of effortful performance of being fine while internally the signal is chaos or silence: you developed adaptations that made sense given what your nervous system was working with. Adaptation is protective. It also has a cost. Adaptations that were built for one environment tend to need recalibration when the environment changes. And sometimes the most useful thing you can do is go back and build the foundation you didn't get to build at the time. You have more resources now and more context, and your nervous system can work with that. It is not starting over. It is picking up a thread that was always yours.
If you or your organization could use an LPC, coach, consultant, or need some training from someone who thinks like this, I am available. And if you want some free resources or to learn more about Neurocontextual Systems Design or Therapy, book a consultation with me.
REFERENCES:
• Friston, K., & Kiebel, S. (2009). Predictive coding under the free-energy principle. Philosophical transactions of the Royal Society of London. Series B, Biological sciences, 364(1521), 1211–1221. https://doi.org/10.1098/rstb.2008.0300
• Mahler, K. https://www.kelly-mahler.com/
• Barrett, L. F. (2017). How Emotions Are Made: The Secret Life of the Brain. Houghton Mifflin Harcourt.
• Bael, Kristen & Scarfo, Jessica & Suleyman, Emra & Katherveloo, Jessica & Grimble, Natasha & Ball, Michelle. (2024). A systematic review and meta-analysis of the relationship between subjective interoception and alexithymia: Implications for construct definitions and measurement. PLOS ONE. 19. 10.1371/journal.pone.0310411.
• Damasio, Antonio. (2010). Self Comes to Mind: Constructing the Conscious Brain.
