Interoception is our internal GPS, a sensory system that helps us navigate the terrain of our bodily functions and emotional states. It's what helps you recognize that you're hungry, thirsty, tired, or emotionally distressed. Far from being just a passive sensor, interoception serves as a dynamic conversation between the body and the brain, shaping our perceptions, decisions, and even our social interactions. It's in this context that psychophysiology—the study of the relationship between the mind and the body—gains relevance. Understanding your body's internal signals doesn't just contribute to physical well-being—it's crucial for emotional health, too.

The concept may seem straightforward, but the underpinnings are a blend of complex neurobiology, psychology, and even philosophy. In terms of brain structure, the insular cortex is the star player, acting as the hub that receives and interprets signals from the entire body. But it doesn't operate in isolation. It's deeply connected to other brain regions responsible for emotion, cognition, and decision-making, making interoception a multi-dimensional experience that affects how we think, feel, and behave. Within this network, exteroceptive sensors, which gauge external stimuli like temperature and touch, also communicate with the insular cortex, providing a holistic view of our internal and external worlds.

Although our understanding of interoception has deep roots in diverse disciplines, from Eastern spirituality to Western medicine, it's only recently that science has begun to scratch the surface. Cutting-edge research in neuroscience and psychology is revealing how this "sixth sense" plays a role in a variety of conditions, from anxiety and depression to eating disorders and even autism. This is where the term "allostatic load," or the wear and tear on the body due to chronic stress, becomes relevant. Effective interoception can help manage this load, influencing both our physical health and our psychological states.

Given the complexities of modern life, interoception is garnering more attention than ever before. Why? Because in an age of constant external stimuli, the ability to tune into oneself is not just soothing; it's necessary for mental health. As a tool for self-regulation, it bridges various domains—physical health, emotional well-being, and even cognitive performance. Here, the psychosomatic connection—how our emotional state can affect our physical health—becomes vitally important. Mastering interoception can, therefore, serve as a preventative measure against psychosomatic illnesses and a cornerstone for comprehensive well-being.

Interoception manifests in various ways, each providing unique insights into your bodily and emotional state. Here's a list that breaks down the many forms of interception:

• Hunger Sensation: This form of interoception tells you when it's time to eat. Your stomach sends signals that it's empty, or ghrelin, the "hunger hormone," spikes, prompting you to seek out food.
• Thirst Perception: Your body alerts you when you're dehydrated or need fluids. This is crucial not just for comfort but for vital functions like temperature regulation and detoxification.
• Pain Awareness: Interoception helps you perceive pain, whether it's a dull ache or a sharp sting. This is the body's way of signaling that something is wrong and needs attention.
• Breath Monitoring: Paying attention to your breath is an interoceptive exercise that can help you become aware of your stress levels and emotional state. It's often used in mindfulness and meditation practices.
• Heart Rate Sensing: Recognizing a fast or slow heartbeat can be a signal of emotional or physical stress. This is why it's often monitored in biofeedback therapies to control stress or anxiety.
• Body Temperature: Feeling hot or cold and the ability to sense feverishness is another form of interoception, guiding behaviors like putting on or taking off layers of clothing.
• Muscle Tension: Sensing that your muscles are tight or relaxed is key for both physical activities, like exercise, and emotional states, like stress or relaxation.
• Gastrointestinal Signals: Your gut is often called the "second brain," and it sends signals that can affect mood and even decision-making, alongside more obvious functions like digestion.
• Sexual Arousal: Interoception helps you become aware of physiological changes related to sexual arousal, such as heart rate increase and muscle tension.
• Fatigue Detection: Your body alerts you when you need rest, whether it's sleep or just a break from physical or mental work.
• Emotional Awareness: While harder to quantify, emotions like happiness, sadness, and anger have physical correlates that interoception helps you tune into, like a lump in your throat or butterflies in your stomach.

The scientific understanding of interoception has expanded significantly in the past few decades, thanks to advances in neuroimaging technologies like fMRI (functional Magnetic Resonance Imaging) and PET scans, as well as rigorous behavioral studies.

Firstly, much of the neural basis for interoception is rooted in the insular cortex—a region of the brain that is known to process bodily sensations and emotional states. Studies have found that the insular cortex is activated when people are asked to focus on internal sensations, whether it's heart rate, breath, or even emotional feelings. This lends credence to the idea that there's a dedicated neural "hub" for interoception.

But it doesn't stop there; the insular cortex is intricately connected to other brain regions like the amygdala, which is involved in emotional processing, and the prefrontal cortex, known for decision-making. This network suggests that interoception isn't just about sensing what's happening inside the body but also about integrating these perceptions into broader cognitive and emotional contexts.

In addition to brain studies, behavioral research has shown correlations between interoceptive awareness and various psychological conditions. For example, people with anxiety disorders often exhibit heightened interoceptive sensitivity, meaning they are extremely tuned into internal sensations like a racing heart or rapid breathing, which can exacerbate their anxious states. Conversely, conditions like depression and some eating disorders are often linked to reduced interoceptive awareness, pointing to a disconnect between bodily sensations and emotional understanding.

Interestingly, interoceptive training, often in the form of mindfulness or meditation, has shown promise as a therapeutic intervention. Clinical studies indicate that learning to tune into one's bodily sensations can help regulate emotional states, reduce stress, and even improve decision-making skills.

So, while the study of interoception is still a growing field, the evidence so far paints a compelling picture of its importance in understanding the intricate interplay between our bodies and minds. Far from being a fringe topic, it can be argued that interoception is becoming central to our understanding of human psychology and well-being. It's a science-backed reminder to "listen to your body," and that's something worth taking seriously.

If you're curious about specific scientific evidence or discussion on our interoceptive mechanisms, here's a list of related research you can check out:

• Gerritsen 2005 discusses the complex molecular pathways involved in hunger and satiety, highlighting the role of proteins like ghrelin and obestatin in signaling hunger and adequacy. Davidson 2005 supports the notion that ghrelin acts as an interoceptive hunger cue, as it produces similar sensory properties to those induced by food deprivation.
• Gizowski 2018 discusses the involvement of higher-order brain regions such as the anterior cingulate cortex and insular cortex in the perception of thirst, while also emphasizing the role of circumventricular organs in monitoring changes in blood osmolality and orchestrating appropriate responses. Millard-Stafford 2012 explores the multifactorial nature of thirst perception, influenced by social and psychological cues, and suggests that perceived thirst and ad libitum drinking are not equivalent measures.
• Ginzburg 2015 found that individuals with higher body awareness were more likely to exhibit complete habituation to pain, especially among those with low levels of pain catastrophizing. However, d'Alcalà 2015 did not find a significant difference in interoceptive awareness and body awareness between individuals with chronic pain and those without.

A more complete list of references can also be found at the bottom of this post.

By tuning into your body's internal signals, you can gain a richer understanding of your emotional landscape, make more informed decisions, and even regulate physiological responses to stress or discomfort. Let's explore some specific examples.

Mental Health

1. Anxiety Management: If you're prone to anxiety, you likely know the feeling of a racing heart or shallow breathing. Using interoception, you can become aware of these early signals and implement calming techniques, like deep breathing or progressive muscle relaxation, before the anxiety escalates. For instance, when you notice your heart rate climbing, you can pause and take five deep, slow breaths, focusing your attention solely on the inhalation and exhalation.
2. Mindfulness for Depression: Interoceptive practices can be particularly beneficial for breaking the cycle of rumination that often accompanies depression. When you catch yourself sinking into a depressive spiral, try a body scan exercise. Focus on each part of your body, starting from your toes and moving upwards, to shift focus away from negative thought patterns and create a grounding experience that moves you into your body and out of your brain.

Physical Health

1. Pain Management: If you suffer from chronic pain, interoception can help you tune into the nuanced sensations around pain zones, allowing you to differentiate between types of pain (sharp, dull, throbbing). You can then tailor your pain management strategies accordingly. For example, recognizing a certain type of back pain could tell you that it's muscular in nature and would benefit from heat therapy rather than cold.
2. Diet and Nutrition: How often do we eat not because we're hungry but because we're bored, stressed, or just because food is available? Practicing interoception can make you more attuned to your body's actual needs. Imagine pausing to do a quick internal "scan" before reaching for that extra snack. Are you really hungry, or are you bored or stressed?

Hybrid (Mental and Physical)

1. Exercise Optimization: Interoception can help you understand your body's signals during exercise, helping you strike a balance between pushing your limits and knowing when to rest. Let's say you're a runner; attuning to your body can help you recognize the difference between the "good" kind of muscle fatigue and the onset of a potential strain or injury.
2. Sleep Quality: Using interoceptive techniques like progressive muscle relaxation before bed can help you tune into any physical tension and release it, promoting better sleep quality. If you often struggle with racing thoughts at bedtime, try a focused breathing exercise to shift your attention away from cognitive stress and towards bodily sensations.

Improving your interoception is a journey of self-discovery that involves both mental and physical practices. Here are some ways to practice or enhance your interoceptive skills:

Mindfulness and Meditation

Mindfulness exercises, which require you to focus on the present moment, are a great starting point for interoceptive training. Basic mindfulness meditation directs your attention to your breath, helping you become aware of each inhalation and exhalation. Over time, this cultivates a broader awareness of other bodily sensations, such as heartbeat, muscle tension, or even emotional states. It's like tuning an instrument; the more you practice, the more refined your awareness becomes.

Body Scans

In a similar vein, body scan meditations can be extremely helpful. Here, you mentally "scan" your body from head to toe, paying close attention to any sensations or areas of tension. This not only enhances your physical awareness but often leads to emotional insights. For instance, you might realize that stress manifests as a clenched jaw or that happiness makes your chest feel lighter.

Journaling

Journaling isn't just for your thoughts and emotions; it can also be an excellent tool for tracking bodily sensations and how they correlate with your emotional state. Write down what you feel and when, and try to identify patterns. This serves two purposes: it enhances your awareness, and it provides you with data that can help you better understand the relationship between your body and mind.

Biofeedback

Biofeedback techniques use electronic monitoring to provide real-time information about physiological functions like heart rate, skin temperature, and muscle tension. This immediate feedback helps you recognize how thoughts and feelings impact your body, making it easier to learn self-regulation techniques.

Physical Activities

Engaging in physical activities like yoga, Tai Chi, or even simple stretching routines can be valuable. These activities force you to pay attention to your body's mechanics, improving your sensory awareness. Plus, they often incorporate breathing exercises, which, as we've seen, are crucial for interoceptive practice.

Consult Experts

If you're having difficulty honing your interoceptive skills, consider consulting professionals. Therapists trained in body-mind techniques can guide you, and workshops or retreats focused on mindfulness, yoga, or somatic experiencing can offer deeper insights.

Practical Application

Finally, try to apply what you've learned in real-world scenarios. When faced with a decision, take a moment to "check in" with your body. What is it telling you? When you're in social situations, use your newfound awareness to gauge your comfort level or emotional state.

The concept of interoception isn't entirely new, but it gained more formal scientific footing in the 20th century. Early discussions of internal sensations can be traced back to philosophical musings and religious texts, where introspection and body awareness were considered a path to enlightenment or self-knowledge. However, it was only in the late 20th century that researchers began to study it systematically. The term itself was coined by British neurophysiologist Charles Sherrington in the early 1900s, but a comprehensive understanding began to emerge much later with advances in neuroimaging techniques. With the ability to look into the brain's activity, scientists started exploring the neurobiology of how we perceive internal bodily states.

Historically, interoception was often relegated to the background in discussions centered around the "five senses." It was considered less important, perhaps because it lacked the immediate, tangible influence that senses like sight and hearing have on our interaction with the external world. In Eastern philosophies and practices like Buddhism and yoga, however, there's been a long-standing recognition of the importance of tuning into one's bodily sensations as a way to achieve mindfulness or spiritual awakening.

Interoception shares conceptual kinship with a range of practices, philosophies, and fields of study across the world, each offering a unique lens through which to explore the relationship between mind, body, and spirit. Below is a thorough breakdown of similar concepts throughout other belief systems from around the world.

Eastern Philosophies

• Qi Gong & Tai Chi: These ancient Chinese practices focus on cultivating and balancing life force, or "Qi," through fluid movements, breathing techniques, and mental focus. Like interoception, they promote an intimate awareness of bodily sensations and how they relate to one's environment.
• Pranayama in Yoga: This is an ancient Indian practice focusing on breath control. The awareness of breath, rhythm, and physical sensation in Pranayama aims to enhance the life force, "Prana," similar to the goals of interoception.
• Vipassana Meditation: Rooted in Buddhist tradition, Vipassana trains you to observe sensations throughout your body objectively, promoting a heightened state of awareness and equanimity.

Western Philosophies & Clinical Practices

• Somatic Psychology: This form of psychotherapy emphasizes the mind-body connection, helping people become aware of their bodily sensations to heal trauma and emotional issues.
• Biofeedback in Psychology: Here, physiological functions are monitored and reported back to you in real-time, enabling a heightened awareness of bodily states.

Indigenous Practices

• Shamanic Journeying: In some indigenous cultures, a trance-like state is induced, often through rhythmic drumming and dance or the use of psychedelic substances, to promote self-awareness and healing. The focus on bodily sensations during the trance is similar to interoceptive practices.

Modern Science

• Polyvagal Theory: This is a biological framework for understanding the human autonomic nervous system and its role in social behavior and stress. The theory encourages people to become aware of their physiological states to better regulate emotions, similar to interoception.

Spiritual Practices

• Kabbalistic Practices: In Jewish mysticism, or Kabbalah, there are exercises that involve focusing deeply on divine names or structures, leading to a form of heightened bodily awareness and inner vision.
• Contemplative Prayer in Christianity: This form of prayer, often associated with mystics like St. Teresa of Avila, involves intense focus and bodily awareness to commune more deeply with the divine.
• Sufi Whirling: This is a form of physically active meditation practiced by Sufi Muslims. The dizzying spinning induces a trance-like state aimed at spiritual transcendence but also brings about deep bodily awareness.
• Chakra Meditation: Originating from ancient Indian traditions, this involves focusing on various energy centers in the body, recognizing each one's unique quality and sensation, somewhat akin to interoceptive awareness.

By understanding these varied practices and philosophies, we can see that the idea behind interoception is not isolated but part of a larger, cross-cultural dialogue about the intrinsic connection between mind, body, and, in some cases, spirit. The diverse approaches not only validate the concept but enrich it by offering various methods and philosophies for exploring inner awareness.

Here's a curated list of books that delve into the subject of interoception, each from a different angle:

• "How Emotions Are Made: The Secret Life of the Brain" by Lisa Feldman Barrett: This book offers groundbreaking research on emotions and the brain, including the role of interoception in shaping our emotional experiences.
• "The Body Keeps the Score: Brain, Mind, and Body in the Healing of Trauma" by Bessel van der Kolk: A seminal work on trauma, this book touches on the importance of body awareness, including interoceptive skills, in healing and understanding trauma.
• "Aware: The Science and Practice of Presence" by Daniel J. Siegel: Siegel explores the science of presence and mindfulness, including the crucial role that interoception plays in achieving a state of awareness.
• "Buddha's Brain: The Practical Neuroscience of Happiness, Love, and Wisdom" by Rick Hanson: This book offers a look into the neuroscience of well-being, touching upon how mindful awareness, which includes interoception, can change the brain for the better.
• "Radical Acceptance: Embracing Your Life with the Heart of a Buddha" by Tara Brach: This book combines Western psychology with Eastern spiritual practices, discussing the importance of body awareness and interoception in achieving radical acceptance.
• "The Polyvagal Theory: Neurophysiological Foundations of Emotions, Attachment, Communication, and Self-regulation" by Stephen Porges: A more technical read, this book delves into the Polyvagal Theory, which has interoception as one of its key components.
• "Interoception: The Eighth Sensory System" by Kelly Mahler: Specifically aimed at understanding interoception as a sensory system, this book is a practical guide aimed at therapists, teachers, and parents.
• "Mindfulness: An Eight-Week Plan for Finding Peace in a Frantic World" by Mark Williams and Danny Penman: Though not solely about interoception, mindfulness practices in the book help in enhancing interoceptive awareness.
• "Waking the Tiger: Healing Trauma" by Peter A. Levine: This book explores the concept of somatic experiencing, a form of therapy that involves understanding and utilizing bodily sensations, including interoceptive awareness, to heal trauma.
• "The Embodied Mind: Cognitive Science and Human Experience" by Francisco J. Varela, Evan Thompson, Eleanor Rosch: This book explores the intersection between cognitive science and human experience, touching on interoception as a part of embodied cognition.

Here are some key figures who have made significant contributions to the understanding and study of interoception:

• Lisa Feldman Barrett: A renowned psychologist and neuroscientist, Barrett has made groundbreaking contributions to the understanding of emotions, including the role of interoception in emotional experiences.
• Bessel van der Kolk: A leading expert in the field of trauma research, van der Kolk has explored the critical role of body awareness, including interoception, in the healing of trauma.
• Stephen Porges: Known for his Polyvagal Theory, Porges has delved into the physiological and psychological importance of interoceptive awareness, especially as it relates to emotional regulation and social engagement.
• Antonio Damasio: A neuroscientist specializing in emotions and feelings, Damasio has examined the role of bodily sensations, including interoception, in decision-making and consciousness.
• Bud Craig: A neuroscientist who has made significant contributions to the study of interoceptive neuroscience, particularly in mapping the insular cortex, which plays a key role in interoceptive processing.
• Kelly Mahler: An occupational therapist and author of "Interoception: The Eighth Sensory System," Mahler has focused on the practical applications of interoception in daily life and therapy.
• Peter A. Levine: Known for his development of Somatic Experiencing, a body-awareness approach to healing trauma, Levine has touched on the significance of interoceptive awareness in this therapeutic model.
• Sarah Garfinkel: A neuroscientist whose work revolves around the relationship between the heart and the brain, Garfinkel has researched how interoceptive signals, such as heartbeat awareness, affect cognitive and emotional processes.
• Jon Kabat-Zinn: While not exclusively focused on interoception, Kabat-Zinn is a significant figure in the field of mindfulness, which inherently involves the practice of interoceptive awareness.
• Daniel J. Siegel: A psychiatrist known for his work in interpersonal neurobiology, Siegel has explored the role of mindfulness and interoceptive awareness in emotional regulation and mental well-being.

Thanks to Jonny Miller for his research into interception and the insights he shares in his course on mastering the nervous system through breathwork and body awareness. Below are many of the sources he has identified and that contributed to his courses and this topic on interception. 

1  ‘What’s Really Impacting Your Decision Making’ by Michael Ashcroft (link)

2  'On the Origin of Interoception' by Ceunen et al., 2016,  (link)

3  ‘Interoceptive Awareness Skills for Emotion Regulation: Theory and Approach of Mindful Awareness in Body-Oriented Therapy (MABT)’ by Price & Hooven, 2018, (link)

4  ’Emotional Resilience in Leadership Report’ by Miller & Chipchase, 2020, (link) 

5  ‘Interoception and Social Connection’ by Arnold et al., Nov 2019, (link)

6 ‘Multidimensional Assessment of Interoceptive Awareness (MAIA)’ Version 2, 2018, (link)

7  ‘The Multidimensional Assessment of Interoceptive Awareness (MAIA),’ Price et al., Nov 2012, (link)

8 ‘Toolkit for Sleep’ Huberman, Sept 2021, (link)

9 ‘Increased dopamine tone during meditation-induced change of consciousness’ by Kyaer et al. 2002, (link)

10 ‘Reconnecting to the Body’ by movement specialist Sam Sager, 2022 (link)