How to Change Your Body: The Science of Interoception and Healing Through Connection to Yourself and Others

By Saga Briggs and Julie Holland

How to Change Your Body provides an enlightening discourse on the missing piece of the mind-body relationship — our need for social connection. 

What if symptoms from some of our most common afflictions—everything from depression and anxiety to addiction and PTSD—could be traced back to a disconnection from our bodies?

How to Change Your Body explores this provocative question through a rigorous yet playful collection of interviews with scientists, somatic workers, and artists from around the world to uncover the social-emotional aspects of so-called mental illnesses. Saga Briggs is our compassionate guide, pairing peer-reviewed research with moving personal vignettes about her journey away from alcohol dependence to draw a profound link between bodily awareness, social connection, and mental well-being. Interoception, regarded by some as our eighth sense, is fundamental to human health and, Briggs argues, lies at the heart of many techniques shown to improve our relationships to ourselves and others, including psychedelic-assisted therapy, synchronous movement, and energy work.

Whether you are facing a mental health diagnosis or simply yearn for a deeper connection to yourself and your community, How to Change Your Body offers a potent antidote to alienation. Through remembering our bodies in all of their intricacy, we can increase our capacity for presence, reconnect with others, and begin to heal.

• Language: English
• Publisher: Synergetic Press
• Release date: Sep 19, 2023
• ISBN: 9781957869117

Saga Briggs

Saga Briggs is a freelance journalist. Her articles on interoception and psychedelics have been published by Scientific American, Aeon+Psyche, and DoubleBlind Magazine. She is a former editor for the MIND European Foundation for Psychedelic Science and former managing editor of InformED, a digital magazine connecting teachers and students with trends in educational psychology. Originally from the Pacific Northwest, she moved to Berlin in 2018 on a gut feeling and continues to move that way. 

Book preview

Introduction

One of the goals of taking psychedelics is to find a way to a certain state of mind without having to take psychedelics.

—Rick Doblin, MAPS

DURING LOCKDOWN IN MARCH 2020, AS THE PANDEMIC DIFFUSED INTO life in Berlin, I had an upsetting but revelatory dream: I was a blank canvas, and other people were the paint that coated me, enlivened me, brought me into being. Without others, I was nonexistent, or at least incapable of seeing myself. Weary of keeping my body alive in such a state of crisis, my brain pivoted out of uncertainty and woke me up.

Oddly enough, in the days of research following the dream, I found that scientists, philosophers, and clinicians were starting to ground this idea in their work: the quality of our connection to ourselves begins with our connection to others—not in a good conversation over coffee, per se, but in the felt experience of being seen by another—and this quality is determined very early in our lives.

At the University of Jyväskylä in Finland, Joona Taipale, PhD, a senior lecturer in the Department of Social Sciences and Philosophy, believes individuality is a developmental process. We are not born with a sense of separateness from others, he says; rather, it’s a gradual process of recognizing our otherness, which develops during infancy.

In developmental psychology, the prevailing notion is that the other—the object—is assumed to be differentiated from the self at the time of birth. But Taipale challenges this idea.

In the psychoanalytic tradition, this picture is turned upside down, he writes in his 2017 paper The Pain of Granting Otherness: Interoception and the Differentiation of the Object. Instead of taking the separateness of others as a point of departure, it argues that the capacity to grant the ‘otherness’ of others is preceded by a long and complex development—a painful process in and through which the object is gradually placed outside the area of the subject’s omnipotent control.

For example, as infants, there’s no reason to assume our mother’s breast (or our mother, for that matter) isn’t part of us, until we develop a sense of agency. Over time, we come to realize this isn’t the case, as we learn the breast (and mother) isn’t always immediately there when we want it, but we begin life under the illusion that it is.

From the point of view of an external observer, the infant and the mother are, of course, two different and distinct entities, he says, but the situation looks very different if considered from the point of view of the infant.

Taipale’s contention? We are born connected.

A team of French neuroscientists takes this notion one step further.

While cognitive psychologists have long tended to consider mental functions—including self-awareness—as isolated entities, recent arguments pointed out the fundamental social nature of self-awareness, writes Nesrine Hazem, PhD, who conducts research for the Social and Affective Neuroscience Laboratory at ICM in Paris. By experiencing the self as the object of another’s attention, infants may develop an initial representation of self and others as psychological entities. Rather than suppressing self-experience in adulthood, social contact would then give rise to the experience of being a cognitive-affective agent. Thus, a fundamental property of social contact throughout the life span would be to enhance self-awareness.

Her team’s own work substantiates the link between not only social contact and self-awareness, but the fundamentally body-based nature of both. We showed that hearing one’s own name spoken by another person and being touched by another person both increased bodily self-awareness, just as perceiving direct gaze does. This provides the first empirical demonstration that social contact irrespective of sensory modality elicits bodily self-awareness. In doing so, it supports the notion of the social nature of the self—i.e., that human self-awareness emerges in interpersonal contacts.

Why does any of this matter? Because nearly every mental illness under the sun—anxiety, depression, addiction, schizophrenia, eating disorders, posttraumatic stress disorder (PTSD)—is associated with impaired bodily awareness. Which, if the social self-awareness theory is correct, suggests they are interpersonal disorders too.

Psychedelic science, a rapidly growing field showing great promise in advancing human health, seems to be revealing a common thread throughout these illnesses: relational disconnection. Not just to ourselves, our bodies, and others—but also to the very fragile threads tying these three things together.   

One of the main drivers behind the therapeutic effects of psychedelics is now thought to be a change in one’s experience of social relationships. As the research is beginning to suggest, that means a change in one’s experience of oneself and one’s body. These things can’t be separated.

But it wasn’t until recently that relationships became a core focus of psychedelic science. Around the time Michael Pollan’s book How to Change Your Mind came out in 2018, researchers believed the hallmark of a transformative psychedelic experience was ego dissolution (or ego death) through a quieting of the default mode network, a region of the brain thought to drive self-referential thinking. Things have evolved since 2018.

It’s not so much the self-loss but rather the connectedness that seems to be driving the well-being, says David Yaden, PhD, who studies transcendent experiences at the Johns Hopkins Center for Psychedelic and Consciousness Research, in an interview with humanistic psychologist Scott Barry Kaufman. He concedes that there’s a correlation between self-loss and connectedness, but his studies show that only connection seems to be correlated with beneficial outcomes related to well-being. I think a lot of researchers are maybe barking up the wrong tree in terms of ego dissolution, and this feeling of social connectedness is where the real action is at. My prediction is that these processes related to social connectedness and attachment will end up being the real mediator in at least some of the therapeutic benefits.

If social awareness, self-awareness, and bodily awareness are inextricably linked, this implies that one important reason psychedelics work to treat a wide range of afflictions is because they have the capacity to change one’s experience of bodily feelings, not just one’s thoughts.  

In Pollan’s book, one depressed patient who had taken psilocybin, the psychoactive compound in magic mushrooms, described his experience as follows: Once I was in this state, it was beautiful—a feeling of deep contentment. I had this overwhelming feeling—it wasn’t even a thought—that everything and everyone needs to be approached with love, including myself.

Although the effect lasted a few weeks, it eventually faded in the following months and his depression returned. One year later he wrote, The insights I gained during the trial have never left and will never leave me. But they now feel more like ideas.

This notion hasn’t escaped more recent psychedelic studies. The Watts Connectedness Scale, for example, provides the first scientific model for measuring feelings of connectedness during psychedelic experiences. Dr. Rosalind Watts and her research team published a paper in 2022 describing their initial findings on the relationship between psilocybin and connectedness in participants with depression. As you might expect, study participants reported feeling more connected to themselves, other people, and the greater world after ingesting psilocybin. Interestingly, few people reported feeling more connected in a singular domain without experiencing greater connectedness in the others.

Based on the findings of this study, we now predict, for example, that an individual reporting feeling connected to a sense of meaning and purpose as well as their body and emotions would also report feeling connected to other people; or that someone describing feeling connected to nature would also report feeling connected to humanity at large and their own emotions, they write. Overall, high scores on one domain (self/others/world) suggest high scores on others, just as low scores in one aspect suggest a disconnection across multiple domains.

To me, this begs the question: is it that psilocybin enhances connectedness by making it feel multidimensional, or that connectedness itself is already multidimensional, and psilocybin reveals it to be so?

One clue, perhaps, is in the way study participants tend to describe their experiences of self-connection: I have felt connected to my body; I have felt connected to my senses; I have felt connected to a range of emotions.

Previous conceptualisations of ‘self-connection’ have been largely cognitive, emotional, and behavioral, and have not included embodied/somatic aspects, Watts and her team report. Self-connectedness in psychedelic therapy tends to be described as connectedness to the senses, the body, and emotions.

When I consider how I’ve managed my own illnesses—substance abuse and anxiety—I notice that the things that worked for me functioned in a very similar way to how MDMA, a psychedelic-type drug known to enhance both bodily awareness and sociality, may work, without MDMA being part of the picture. It was a resocialization process, and it happened through my body.

Is it the bodily experience that we should be honoring and paying more attention to, with or without psychedelic drugs, when it comes to mental health treatment?

For the past three years, a large part of my journalistic efforts have been aimed at answering this question through the lens of interoception, the process of sensing the body from within. Increased capacity for interoception—considered by some to be the eighth sense—relieves mental illness and promotes well-being by helping us connect to ourselves and others, and plays an underacknowledged role in a wide range of wellness practices and treatments, from yoga to psychedelic therapy. What follows is a summary of what I’ve learned so far, from the scientific literature, from researchers and practitioners around the world, and from my own personal science and reflection. Much like psychedelic research, the research on interoception is just arriving, but that doesn’t mean we can’t use our imaginations, be right about the things we imagine, and start putting them into practice now.

This is a book about connection. It is also an argument for reframing mental health as relational health. Because the number one thing that soothes the nervous system, and does not damage it over time—that makes the body feel safe, allowing the mind to follow—is authentic human connection. 

I. PREDICTING THE BODY

Predicting the Body

For six years, I drank to connect. It began in 2011 in Ohio, like the flip of an epigenetic switch, taking a shot of rum from the kitchen cupboard before going to meet some college friends I wanted to impress. Five years later, I found myself knocking back Negronis on a Monday night in Seattle until I couldn’t stand up. Once I scaled it back, my withdrawal symptoms lasted a full year. It took me two more to stop drinking completely. 

When we talk about using substances to numb, we’re suggesting that we don’t want to feel. But humans never stop feeling. As the neuroscientist Antonio Damasio said, Humans are not thinking machines; humans are feeling machines that think. I used alcohol to control the way I felt, and to reduce uncertainty around how I would feel. I didn’t drink to numb. I drank to predict.

PREDICTIVE CODING

One of the most widely accepted accounts of human brain function is the predictive coding theory, which argues that the brain evolved to generate a reliable model of the world around us and eliminate false guesses as efficiently as possible. According to this theory, the brain creates models for our perception, concepts, and feelings based on experience, and anything falling outside these models results in a prediction error, which is then either updated by new information (adapting to the temperature of a hot bath) or by prior beliefs (the feeling of having a real limb where one is missing, as in phantom limb syndrome). Although it’s meant to serve an adaptive function, too much prediction in the wrong direction can trap us into destructive belief systems and habits, including substance abuse.

I used to know exactly how confident I would be on a date after two gin and tonics. I knew how thick to slice a lime to stuff the pulpy wedge into the neck of a Pacifico, and how the first sip meets your lime-slicked lips and jazzes on the tongue. I knew the protective warmth of Yellow Tail shiraz, sails lifting the solar plexus, expanding the space between the ribs. I knew the proud feeling of being the cool girl who orders a White Russian or a whiskey neat.

When I went out with my boyfriend and our friends in Portland, Oregon, back in 2012–2013, I would usually start with cocktails or a shot, then switch to beer. Whatever chemistry occurred in my brain as a result of that order of things seemed to improve my memory, focus, and attention in a way that made socializing easier. Normally, for example, I might be trying to tell a story and be hypervigilant about other people’s perceptions of me while I was telling it, which takes mental resources away from the actual telling of the story. But liquor made it easier to eliminate that hypervigilance and focus on myself, which led to better storytelling. I came to associate a Fireball and a High Life with social performance, and my prediction rarely failed me. I also knew that if I started the night with beer or wine, my thinking became muddled and my brain fuzzy, which made it harder to hold a conversation, so I avoided that.  

Predictive coding affects the entire nervous system (e.g., knowing something in your heart has a real physiological basis) and is closely tied to a process called interoception, which is our sense of what’s going on inside our bodies. Any jitters I had before that first drink are an example of the elegant interplay between interoception and predictive coding: my body recognized an environment (bar, social gathering) where it could predict the conditions under which I would be nervous or relaxed, and if the conditions for relaxation weren’t yet available (read: prediction error), I’d feel nervous. Once I consciously picked up on that nervousness, the predictive coding kicked into full force and I couldn’t relax until I resolved the prediction error with a shot and a beer back. Alcohol dependence became a rigid predictive mold encasing my nervous system.

In the most general terms, interoceptive perceptions—that is, what is experienced—derive from the brain’s best guess about the causes of events in the body, with incoming sensory inputs keeping those guesses in check, says Lisa Feldman Barrett, PhD, who pioneered the EPIC (Embodied Predictive Interoception Coding) model of cognition. Not only has your past sensory experience reached forward to create your present experience, but how your body feels now will again project forward to influence what you will feel in the future. It is an elegantly orchestrated self-fulfilling prophecy, embodied within the architecture of the nervous system.

In other words, not only does information flow from our senses to our higher faculties to be processed so we can understand and interact with the world, but those higher faculties also often predict the input from our environment, thereby influencing our perception of the world before we actually get a chance to sense it.

You experience, in some sense, the world that you expect to experience, says Andy Clark, DPhil, a cognitive scientist at the University of Edinburgh in Scotland. All experience is controlled hallucination.

Again, the reason for this controlled hallucination is efficiency: think of the way a computer stores video files, which contain enough redundancy from one frame to the next that it’s more efficient to encode the differences between adjacent frames and then work backward to interpret the entire video than to encode every pixel in every image when compressing the data. Memory is thought to work the same way, eliminating nuance and preserving the gist of the experience.

But when it comes to circumventing this self-fulfilling prophecy, and not only creating behavior change but rewiring your own predictions, the more energetically efficient solution may be to extract the data and consider each pixel. And when that happens, the body—not the mind—is the first player up to bat.

Recently, there has been much interest in the concept of predictive coding in interoception, neuroscientists Karen Dobkins, PhD, and Andy Arnold, PhD, write in a theoretical paper on the topic. Here, the notion is that, as part of homeostatic processes, the interoceptive system tries to minimize errors between what is predicted versus actual, since errors are energetically expensive. While they agree that prediction errors are energetically expensive, they also note that reinforcing one’s predictions can itself be expensive, especially in the social domain. A concrete example of this might be ‘getting worked up’ about an upcoming presumed-difficult conversation. This can be exhausting, not to mention the fact that bracing for a difficult conversation can lead to a negative self-fulfilling prophecy. We suggest that the most energetically efficient solution is to acknowledge one’s priors and yet go into a social interaction with a ‘beginner’s mind,’ staying present to, and trusting, one’s interoceptive signals as the situation unfolds.

To sit with uncertainty—the feeling, not the concept—is the first step toward knowing.

INTEROCEPTION

One rainy day in Portland, in the fall of 2016, I was writing and listening to Bob Dylan’s Blood on the Tracks when I noticed my fingers trembling as I held them over my keyboard. I knew what was happening. I’d been experimenting with drinking less in the previous few months, and this was my body’s reaction to it. The strange thing was that I’d felt fine on the inside, at least most of the time, for the entire five years prior to cutting back. But it struck me in that moment that I must not have been fine, despite thinking I was fine, and that somehow I must have missed the part where my body warned me things were getting bad.

Instead of noticing two main body states—less relaxed before an expected drink and more relaxed after an expected drink—I began having no frame around my feelings. One night I helped my brother-in-law set up appetizers in his kitchen as guests arrived for dinner, and the anxiety was like the flash of a camera inside me, a photonic fear, my body sublimating on the spot. I worried about my body most of all—how to arrange it in space around others, where to be, how to stand, how to occupy time and space in a suitable embodied rhythm. Speaking was a physical act, too: would I try to be connected to the words coming out of my mouth, or would it be easier to stay disem-bodied and follow a script? The more I thought about these things, the less grounded in my body I was and the less of a chance there was for my authentic self to show up at the party. 

In 2017, I went to Paris to stay with a French boyfriend I’d met while traveling. In some ways I could not summon the life force to participate in normal things. I couldn’t rent bikes with him because the whole thing seemed to require too much energy. If we weren’t drinking, I’d just want to go back to his flat and lie in bed and watch a movie while the sun shone outside and tourists scaled the Eiffel Tower. We were doing the non-touristy thing, I told myself, just living the way Parisians live. My hand shook under the blanket, completely out of control, as we snuggled up around his laptop screen. Alongside these withdrawals, I started noticing these moments of love for him that filled me completely. It was everywhere in my body at once. My chest, my arms, parts of my body I couldn’t name. It seemed to glow without a point of origin.

It was as if I’d opened a floodgate in the previous six months and all sensations—pleasant and unpleasant, exaggerated and exact—were rushing through at once. While some of the feelings were transformative in a positive way, many were debilitating. In fact, it was quickly becoming clear that I could not love a person fully while my body lived in fear. I wanted to know: how could I regain control over my situation, how could I inhabit a different reality, how could I change my body?

All of these experiences fall under the category of interoception. As I said before, interoception is the process of sensing the body from within. It’s how we know when we’re thirsty, hungry, horny, joyful, anxious, tired, angry, sick, elated. A lesser known sense compared to the main five (which are collectively called exteroception), interoception is like mindfulness for the body—it’s what allows us to be aware of our own well-being. And it’s unique for everyone, although it’s generalizable enough that we can often understand each other’s descriptions of interoceptive sensations. 

You may have noticed that emotional and physical feelings are part of the same list. That’s because the interoceptive process that allows us to sense the state of our internal organs also allows us to experience and regulate emotion. Although it wasn’t always believed that emotions arise from anywhere but the mind, neuroscientists have found that the same part of the brain—the insular cortex (or insula)—is a primary hub for body sensing and emotion processing. We tend to think that signals for emotions like joy or anger have nothing to do with signals for body processes like hunger and thirst, but this is a mistake. They are part of the same interoceptive system. Body and emotion are inseparable. 

Along these lines, Dobkins and Arnold argue that loneliness is a social hunger signal, managed by the same process as hunger for food. In their view, a healthy social existence is not defined by the number of connections you have, but by listening closely to what’s going on inside your body.

At least for physiological needs, they say, "we (and all animals) have evolved mechanisms to 1) sense current amounts of resources as well as 2) motivate behavior to acquire needed resources. For example, ‘hunger’ is a sensation that signals a lack of food, inciting us to acquire that resource, else we would die of starvation. The mechanism for sensing hunger is interoception—a system for sensing internal physiological states of the body (e.g., hunger, thirst, temperature) as a means of regulating and maintaining homeostatic conditions."

Similar to physical hunger, they say, social hunger should serve to motivate social (re)connection. They propose that interoception plays an important role in indicating whether one feels lonely or socially connected—i.e., adequate interoception may buffer one from loneliness.

But you have to pay attention to your body to recognize the signal.

One may ignore (or be insensitive to) one’s feelings of loneliness, similar to ignoring physical hunger pains, and therefore not be motivated to (re) connect with others, they write. Or you might recognize the signal but avoid responding to it socially because of a negative past experience: One may actively avoid the social world because past social interactions have been low quality and therefore, unrewarding. Over time, this could also lead us to ignore the signal.

The point to remember is that bodily signals often precede emotion, and it is specifically our awareness and interpretation of those signals that allow the construct of emotion to arise at all.

One of the first psychologists to suggest that body states precede emotions was William James. James believed our heart pounds not because we are anxious, but rather that we’re anxious because our heart pounds. Certainly, believing we’re anxious may cause our heart to pound even harder, but the reason our heart starts pounding initially is for a fairly neutral reason: it’s alerting us to something important, something that most likely requires our attention and energy. It’s our subjective interpretation of the pounding heart as anxiety, fear, or panic that induces the unpleasant emotional state that follows. The bottom line is that we can learn to interpret—and respond to—the signal in healthier ways.

You can already start to see how faulty interoception might lead to sustained illness.

One of the world’s foremost authorities on interoception is Sarah Garfinkel, PhD, a clinical affective neuroscientist at University College London. She subscribes to James’s notion of emotions arising from body states, and thinks interoception is behind it. Much of her work focuses on heartbeat perception, which is closely related to emotion in the brain. What often happens in the case of mental illness, she believes, is that people become disconnected from truly understanding what’s happening inside their bodies. 

"It was actually PTSD that