On the Origin of Interoception

The neurobiology of interoception and affect

Scholars have argued for centuries that affective states involve interoception, or representations of the state of the body. Yet, we lack a mechanistic understanding of how signals from the body are transduced, transmitted, compressed, and integrated by the brains of humans to produce affective states. We suggest that to understand how the body contributes to affect, we first need to understand information flow through the nervous system's interoceptive pathways. We outline such a model and discuss how unique anatomical and physiological aspects of interoceptive pathways may give rise to the qualities of affective experiences in general and valence and arousal in particular. We conclude by considering implications and future directions for research on interoception, affect, emotions, and human mental experiences.

Aberrant heartbeat-evoked potential in schizophrenia

Self-disturbance is considered a core feature underlying the psychopathology of schizophrenia. Interoception has an important role in the development of a sense of self, leading to increased interest in the potential contribution of abnormal interoception to self-disturbances in schizophrenia. Several neuropsychological studies have demonstrated aberrant interoception in schizophrenia. However, cortical interoceptive processing has not yet been thoroughly investigated. Thus, we sought to examine resting-state heartbeat-evoked potential (HEP) in this population. We hypothesized that patients with schizophrenia would exhibit significant alterations in HEP compared to healthy controls (HCs). In this cross-sectional electroencephalogram (EEG) study, we compared the HEPs between age- and sex-matched groups of patients with schizophrenia and HCs. A 10-min resting-state EEG with eyes closed and an electrocardiogram (ECG) were recorded and analyzed for the time window of 450 ms to 500 ms after an ECG R peak. A positive HEP shift was observed in the frontal-central regions (F [1, 82] = 7.402, p = 0.008, partial η2 = 0.009) in patients with schizophrenia (n = 61) when compared with HCs (n = 31) after adjusting for confounders such as age, sex, and heart rate. A cluster-based correction analysis revealed that the HEP around the right frontal area (Fp2, F4, and F8) showed the most significant group differences (F [1, 82] = 10.079, p = 0.002, partial η2 = 0.021), with a peak at the F4 electrode site (F [1, 82] = 12.646, p < 0.001, partial η2 = 0.069). We observed no correlation between HEP and symptoms in patients with schizophrenia. A positive shift of HEP during the late component could reflect a trait abnormality in schizophrenia. Further research is required to determine the association between the altered cortical interoceptive processing indexed with HEP and self-disturbances in schizophrenia.

A roadmap to understanding interoceptive awareness and post-traumatic stress disorder: a scoping review

The concept of interoception has existed since the beginning of the 1900s. It is suggested that humans can observe feelings arising from the body that allows them to develop a sense of their emotional status and physical condition. The term interoceptive awareness appears to originate with clinicians working with individuals who had experienced trauma, in particular Post Traumatic Stress Disorder (PTSD). The purpose of this scoping review was to provide an overview of the existing literature surrounding the combination of these two themes: interoceptive awareness and PTSD. A total of 226 articles were initially screened and 52 articles were retained for comprehensive review. Nine articles were excluded, resulting in 43 studies included in the review. The review aimed to answer: (a) how is interoceptive awareness defined? (b) how is interoceptive awareness measured? (c) what is the function of interoceptive awareness? (d) is there/what is the relationship between interoceptive awareness and PTSD? The scoping review identified nine terms that are used synonymously throughout the literature surrounding interoceptive awareness and PTSD, and three primary ways in which interoceptive awareness is measured in relation to PTSD. The primary function documented was the role interoceptive awareness played in an individual's ability to regulate their emotions, and the most common and compelling function emerging was the association with emotion regulation. The evidence supports the utilisation of a definition of interoceptive awareness to include one that includes the quality of cognitive appraisal and focuses on the adaptive mindful approach to internal physical sensations as opposed to the heightened ruminative self-focus. Limitations and future research are suggested.

Disrupted interoceptive awareness by auditory distractor: Difficulty inferring the internal bodily states?

Recent studies have associated interoceptive awareness, the perception of internal bodily sensations, with a predictive mechanism of perception across all sensory modalities. According to the framework, volitional attention plays a pivotal role in interoceptive awareness by prioritizing interoceptive sensations over exteroceptive ones. Consequently, it is hypothesized that the presence of irrelevant stimuli would disrupt the attentional modulation and interoceptive awareness, which remains untested. In this study, we investigated if interoceptive awareness is diminished by unrelated auditory distractors to validate the proposed perceptual framework. A total of 30 healthy human volunteers performed the heartbeat counting task both with and without auditory distractors. Additionally, we measured participant's psychophysiological traits related to interoception, including the high-frequency component of heart rate variability (HF-HRV) and trait interoceptive sensibility. The results showed that interoceptive accuracy, confidence, and heartbeat intensity decreased in the presence of distractor sound. Moreover, individuals with higher HF-HRV and a greater tendency to worry about bodily states experienced a more pronounced distractor effect on interoceptive awareness. These results provide support for the perceptual mechanism of interoceptive awareness in terms of the predictive process, highlighting the impact of relative precision across interoceptive and exteroceptive signals on perceptual experiences.

An Overview of the Bodily Awareness Representation and Interoception: Insights and Progress in the Field of Neurorehabilitation Research

In the last two decades, the scientific literature on so-called body representations has been increasing, and the notion of body awareness (BA) is particularly interesting for neurorehabilitation. In this article, we present results derived from recent studies on this representation, considering the different definitions and explicative models proposed as well as the empirical settings used to test it, providing an extensive overview of these issues. This article discusses the challenge of understanding how we integrate the sensory experiences of proprioception (knowing where our body is in space) and interoception (sensing internal bodily sensations, like hunger of thirst) with our perception of self. This is a difficult problem to analyze because our awareness of our body is inherently linked to our perspective, since the body is the means through which we interact with the world. Presenting the different viewpoints offered by recent theories on this concern, we highlighted that the neurorehabilitation and psychiatric settings offer two important fields useful for the study of BA because in them it is possible to analyze bodily representations by inducing/observing a controlled discrepancy between dysfunctional content and sensory inputs.

A computationally informed distinction of interoception and exteroception

While interoception is of major neuroscientific interest, its precise definition and delineation from exteroception continue to be debated. Here, we propose a functional distinction between interoception and exteroception based on computational concepts of sensor-effector loops. Under this view, the classification of sensory inputs as serving interoception or exteroception depends on the sensor-effector loop they feed into, for the control of either bodily (physiological and biochemical) or environmental states. We explain the utility of this perspective by examining the perception of skin temperature, one of the most challenging cases for distinguishing between interoception and exteroception. Specifically, we propose conceptualising thermoception as inference about the thermal state of the body (including the skin), which is directly coupled to thermoregulatory processes. This functional view emphasises the coupling to regulation (control) as a defining property of perception (inference) and connects the definition of interoception to contemporary computational theories of brain-body interactions.

Disturbed interoception in body dysmorphic disorder: A framework for future research

Body dysmorphic disorder is a severe psychiatric condition characterised by a preoccupation with a perceived appearance flaw or flaws that are typically not observable to others. Although significant advances in understanding the disorder have been made in the past decade, current explanations focus on cognitive, behavioural and visual perceptual disturbances that contribute to the disorder. Such a focus does not consider how perception of the internal body or interoception may be involved, despite (1) clinical observations of disturbed perception of the body in body dysmorphic disorder and (2) disturbed interoception being increasingly recognised as a transdiagnostic factor underlying a wide range of psychopathologies. In this paper, we use an existing model of hierarchical brain function and neural (predictive) processing to propose that body dysmorphic disorder involves defective interoception, with perceived appearance flaws being the result of 'interoceptive prediction errors' that cause body parts to be experienced as 'not just right'. We aim to provide a framework for interoceptive research into body dysmorphic disorder, and outline areas for future research.

The effect of 10-week long yoga training on interoceptive abilities: cross-sectional and longitudinal investigation of cardiac and gastric accuracy

Based on their characteristics, it is likely that mind-body techniques develop interoception, the perception of bodily state. Nevertheless, findings on mindfulness, meditation, yoga, and body scan techniques are inconclusive. Additionally, the methodological scope is not exhaustive, neither in terms of the intervention nor the applied measure of interoception. This study investigated for the first time the effect of regular yoga training on cardiac and gastric perceptual ability (measured with the mental heartbeat tracking task and the water load task, respectively). With the involvement of 90 female university students (yoga group n = 57, control group n = 33) we did not find any connection between baseline heartbeat perception score and gastric fullness. Moreover, the applied 10-week-long regular yoga training did not develop any of the measured interoceptive abilities. We conclude that yoga might develop other abilities than these specific sensations. Very probably, the measured cardiac and gastric perceptual abilities do not represent bodily sensations in general. It would be worth to investigate, however, the effect of longer yoga training on interoception.

Interoceptive experiences and ecological care: an embodied approach within therapeutical realms

The conventional dichotomy between human health and disease has historically been approached through reductionist models that emphasize the exclusive causal relevance of physiological and pathological processes. Consequently, self-awareness and affective dimensions, integral to a phenomenological perspective, are often relegated to secondary traits, affording little consideration for the causal role of embodied living organization. Our interest lies in exploring the potential relevance of the phenomenology of embodied self-awareness in relation to interoceptive processes within therapeutic settings. As we illustrate, when the unfolding processes of interoceptive awareness and its affective capacity take precedence, the agent assumes an active, rather than passive, role in their own experience of health or illness. Departing from an enactive, phenomenological, and ecological standpoint, we propose a distinctive perspective on interoceptive processes, relying on an affective conceptualization of a spectrum of experiences of bodily being-in-the-world. Our primary argument posits that considering interoceptive processes from an embodied and ecological viewpoint of the self, interacting with the material and social environment, enables an approach to the gradient of affective experiences of embodied self-awareness-where pleasure or suffering is perceived and felt-in a naturalized, non-reductive, and relational manner. We discern two ways in which interoceptive processes interrelate with the experience of embodied self-awareness: sensitivity (self-affective) and affective-laden perception. Drawing on this distinction, we provide a nuanced description of these experiences within communities of cis-women, exemplified through the contexts of menstruation and endometriosis. This exploration seeks to enhance our understanding of the phenomenology of embodied, ecological, and affective self-experience from within diverse and situated bodies. The goal is to contribute to their autonomy and ability to adapt and self-regulate within therapeutic contexts.

A conceptual framework on body representations and their relevance for mental disorders

Many mental disorders are accompanied by distortions in the way the own body is perceived and represented (e.g., eating disorders, body dysmorphic disorder including muscle dysmorphia, or body integrity dysphoria). We are interested in the way these distortions develop and aim at better understanding their role in mental health across the lifespan. For this purpose, we first propose a conceptual framework of body representation that defines this construct and integrates different perspectives (e.g., cognitive neuroscience, clinical psychology) on body representations. The framework consists of a structural and a process model of body representation emphasizing different goals: the structural model aims to support researchers from different disciplines to structure results from studies and help collectively accumulate knowledge about body representations and their role in mental disorders. The process model is reflecting the dynamics during the information processing of body-related stimuli. It aims to serve as a motor for (experimental) study development on how distorted body representations emerge and might be changed. Second, we use this framework to review the normative development of body representations as well as the development of mental disorders that relate to body representations with the aim to further clarify the potential transdiagnostic role of body representations.

Changes in Interoception in Mind-body Therapies for Chronic Pain: A Systematic Review and Meta-Analysis

BACKGROUND

Emerging literature has demonstrated deficits in interoception (i.e., the perception of physical sensations from inside the body) in individuals with chronic pain conditions. Mind-body therapies (MBTs) are purported to improve chronic pain in part through improving or restoring interoceptive abilities. The present systematic review and meta-analysis aimed to examine changes in interoception in MBTs for chronic pain conditions.

METHODS

A systematic search of PubMed, PsycINFO, Scopus, CINAHL, and ProQuest Dissertation and Theses was conducted from database inception to February 2023. English language intervention studies evaluating the effect of MBTs on interoception in adults with chronic pain conditions were examined. Changes in pain (severity and interference) following treatment were examined as secondary outcomes.

RESULTS

A total of 11 studies (10 unique samples) were identified. Meta-analytic results reveal significant improvements in total interoceptive awareness (Becker's d = 1.168, p < .01) as well as improvements in seven of eight subdomains of interoceptive awareness (ds = 0.28 to 0.81). MBTs were also associated with reductions in both pain intensity (d = -1.46, p = .01) and pain interference (d = -1.07, p < .001).

CONCLUSIONS

Preliminary research suggests that MBTs demonstrate improvements in interoceptive awareness and reduce pain in adults with chronic pain. Literature on changes in other domains of interoception, such as interoceptive accuracy, following MBTs is severely lacking. Although more rigorous studies are needed to corroborate results, the present findings lay an important foundation for future research to examine interoception as a possible underlying mechanism of MBTs to improve pain outcomes.

Experiences of participating in a group-based sensory modulation intervention for mental health service users

BACKGROUND

People with mental health issues often experience difficulties with sensory modulation affecting occupational engagement. Research conducted in inpatient units has shown positive effects of individual sensory modulation interventions, however, research on experiences of group-based interventions in outpatient units is limited. Hence, a group-based sensory modulation intervention was adapted and tested within Swedish mental health outpatient units.

AIM

To explore the experiences of participating in a group-based sensory modulation intervention for service users in mental health outpatient units.

MATERIAL AND METHODS

This qualitative study involved interviews with 25 informants who had participated in the intervention. The interview data were analysed using reflexive thematic analysis.

RESULTS

Synthesis of the interviews resulted in one overarching theme of 'Embodied awareness facilitates improved coping and sense of self' organised into four themes: (1) 'Developing embodied awareness and strategies', (2) 'Taking control of everyday life', (3) 'Creating a stronger sense of self', and (4) 'From alienation to belonging'.

CONCLUSION AND SIGNIFICANCE

The informants experienced the intervention to provide new embodied coping strategies that had previously been neglected. This understanding may enrich occupational therapy practice in new ways to support service users' engagement in occupations.

Interoceptive Awareness Among the General Public in Saudi Arabia: A Cross-Sectional Study

Background Interoception refers to the cognitive process of perceiving internal bodily states. This encompasses various physiological indicators, including heart rate fluctuations, stomach distention, internal temperature, hydration levels, sensory input from free nerve terminals in the fascia and muscles, as well as hormonal, stretch, and pain receptors. This study aimed to examine the interoceptive awareness among the general public in Saudi Arabia. Methods A cross-sectional online survey was undertaken in Saudi Arabia to investigate the level of interoceptive awareness within the overall population of the country in October 2023. This research used a previously developed questionnaire named the Multidimensional Assessment of Interoceptive Awareness, version 2 (MAIA-2). In a binary logistic regression analysis, the mean interoceptive awareness score of the participants was utilized as the dummy variable to determine the variables that influence interoceptive awareness. Results A total of 814 participants were involved in this study. Overall, the study participants demonstrated a marginal level of interoceptive awareness with a mean score of 94.3 (standard deviation (SD): 29.3) out of 185 (representing 51.0% of the maximum attainable score). The mean interoceptive score was not consistent across different subscales and ranged between 37.7% and 63.3%. The highest mean interoceptive score was observed for the Trusting subscale (9.5 (SD: 4.5) out of 15) (representing 63.3% of the maximum attainable score for this subscale). The lowest mean interoceptive score was observed for the Not-Distracting subscale (11.3 (SD: 6.9) out of 30) (representing 37.7% of the maximum attainable score for this subscale). Binary logistic regression analysis did not identify any statistically significant difference in the likelihood of having a higher level of interoceptive awareness among the participants based on their demographic characteristics (p>0.05). Conclusion The participants in our research demonstrated a modest degree of interoceptive awareness. The study's results suggest that the participants demonstrated a heightened inclination towards internal experiences rather than being attentive to their bodily sensations. Further investigation is required to examine interoceptive awareness across various cohorts.

Thermosensory thalamus: parallel processing across model organisms

The thalamus acts as an interface between the periphery and the cortex, with nearly every sensory modality processing information in the thalamocortical circuit. Despite well-established thalamic nuclei for visual, auditory, and tactile modalities, the key thalamic nuclei responsible for innocuous thermosensation remains under debate. Thermosensory information is first transduced by thermoreceptors located in the skin and then processed in the spinal cord. Temperature information is then transmitted to the brain through multiple spinal projection pathways including the spinothalamic tract and the spinoparabrachial tract. While there are fundamental studies of thermal transduction via thermosensitive channels in primary sensory afferents, thermal representation in the spinal projection neurons, and encoding of temperature in the primary cortical targets, comparatively little is known about the intermediate stage of processing in the thalamus. Multiple thalamic nuclei have been implicated in thermal encoding, each with a corresponding cortical target, but without a consensus on the role of each pathway. Here, we review a combination of anatomy, physiology, and behavioral studies across multiple animal models to characterize the thalamic representation of temperature in two proposed thermosensory information streams.

The evolutionary psychology of ownership is rooted in the Lockean liberal principle of self-ownership

The psychology of ownership is rooted in self-ownership. The human brain has an evolved interoceptive sense of owning the body that supports self-ownership and the ownership of external things as extensions of the self-owning self. In this way, evolutionary neuroscience supports a Lockean liberal conception of equal natural rights rooted in natural self-ownership.

The thermoception task: a thermal imaging-based procedure for measuring awareness of changes in peripheral body temperature

Although thermal body signals provide crucial information about the state of an organism and changes in body temperature may be a sign of affective states (e.g., stress, pain, sexual arousal), research on thermal awareness is limited. Here we developed a task measuring awareness of changes in peripheral body temperature (thermal interoception) and compared it to the classical heartbeat counting task (cardiac interoception). With an infrared light bulb we delivered stimuli of different temperature intensities to the right hand of 31 healthy participants. Thermal interoceptive accuracy, i.e., the difference between participants' real and perceived change in hand temperature, showed good interindividual variability. We found that thermal interoception did not correlate with (and was generally higher than) cardiac interoception, suggesting that different interceptive channels provide separate contributions to awareness of bodily states. Moreover, the results hint at the great salience of thermal signals and the need for thermoregulation in day-to-day life. Finally, thermal interoceptive accuracy was associated with self-reported awareness of body temperature changes and with the ability to regulate distress by focusing on body sensations. Our task has the potential to significantly increase current knowledge about the role of interoception in cognition and behavior, particularly in social and emotional contexts.NEW & NOTEWORTHY We developed a novel task measuring awareness of changes in peripheral body temperature (i.e., thermal interoception). To avoid tactile confounds present in existing thermoceptive tasks, we used an infrared light bulb to deliver stimuli of different temperature intensities to the hand of participants and asked them to judge the perceived change in their hand temperature. Performance in the task showed good interindividual variability, did not correlate with cardiac interoceptive tasks, and was associated with self-reported thermosensitivity.

Mind your heart to bear the weight: Cardiac interoception predicts action-related visual perception when wearing a heavy backpack

Visual perception can be modulated by the physiological potential for action. For instance, it was famously shown that a geographical slant appears steeper when wearing a heavy backpack than not wearing any. However, those results are not always replicated. In the present exploratory study, we test the hypothesis that the backpack weight's effect on perception relies on the ability of the cognitive system to integrate the physiological constraint's change rather than the change itself. Young adults (n = 54) wore an electrocardiogram monitor and completed a computerised task in which photographs of real geographical slants were displayed on a screen while wearing a heavy versus light backpack. The activity of the vagus nerve, as an index of physiological adaptability, was recorded as a proxy of the physiological state during the task. The participants also completed an interoception task assessing one's ability to detect his or her own heartbeat as the index of integration ability of the cognitive system. While Bayesian analyses revealed no difference in angle estimation between carrying a heavy versus light backpack, the results indicated that interoception predicted less accurate angle estimation only when wearing a heavy backpack. In contrast, there was anecdotal evidence that vagal activity changes predicted visual perception. Interoception might thus play a crucial role in the interplay between the physiological potential for action and action-related visual perception.

Interoception, alexithymia, and anxiety among individuals with alcohol use disorder

Background

Interoception (i.e., the ability to recognize bodily signals), alexithymia (i.e., the inability to recognize emotional states) and negative affect (i.e., unpleasant feelings such as anxiety) have been associated with alcohol use disorder (AUD). Previous research suggests that interoception may underlie alexithymia, which in turn may be associated with negative affectivity. However, this remains to be empirically tested. This study investigates whether alexithymia mediates the association between interoception and anxiety and whether this association differs across individuals with AUD and a healthy control (HC) comparison group.

Methods

The AUD group consisted of 99 participants enrolled in an 8-week abstinence-based inpatient treatment program. The HC group included 103 healthy individuals. The heartbeat counting task (HCT) was used to assess interoception (cardiac interoceptive accuracy). The Toronto Alexithymia Scale (TAS-20) was used to assess alexithymia. The Brief Symptom Inventory (BSI) was used to assess anxiety.

Results

The moderated mediation model with interoception as the predictor, alexithymia as the mediator, and negative affect (i.e., state anxiety) as the dependent variable was tested. The analysis showed that the conditional indirect effect of interoception on anxiety via alexithymia was significant for individuals with AUD [ab = -0.300, bootstrap 95% CI = (-0.618, -0.088)], as well as for HCs [ab = -0.088, bootstrap 95% CI = (-0.195, -0.014)]; however, the conditional indirect effect significantly differed across HCs and individuals with AUD. Namely, the mediated effect was greater among individuals with AUD compared to the HC group.

Conclusion

The results suggests that interoceptive impairment contributes to greater negative affect (i.e., state anxiety) via alexithymia especially for individuals with AUD. Improving emotion recognition via therapeutic methods focused on strengthening interoceptive abilities could improve outcomes for individuals receiving treatment for AUD.

Discrepancies in the Definition and Measurement of Human Interoception: A Comprehensive Discussion and Suggested Ways Forward

Interoception has been the subject of renewed interest over the past 2 decades. The involvement of interoception in a variety of fundamental human abilities (e.g., decision-making and emotional regulation) has led to the hypothesis that interoception is a central transdiagnostic process that causes and maintains mental disorders and physical diseases. However, interoception has been inconsistently defined and conceptualized. In the first part of this article, we argue that the widespread practice of defining interoception as the processing of signals originating from within the body and limiting it to specific physiological pathways (lamina I spinothalamic afferents) is problematic. This is because, in humans, the processing of internal states is underpinned by other physiological pathways generally assigned to the somatosensory system. In the second part, we explain that the consensual dimensions of interoception are empirically detached from existing measures, the latter of which capture loosely related phenomena. This is detrimental to the replicability of findings across measures and the validity of interpretations. In the general discussion, we discuss the main insights of the current analysis and suggest a more refined way to define interoception in humans and conceptualize its underlying dimensions.

Development and validation of the Exteroceptive Body Awareness (EBA-q) questionnaire

The conscious processing of body signals influences higher-order psychological and cognitive functions, including self-awareness. Dysfunctions in the processing of these signals has been connected to neurological and psychiatric disorders characterized by altered states of self-consciousness. Studies indicate that perceiving the body through interoceptive signals (e.g., from internal organs such as heartbeat and breathing) is distinct from perceiving the body through exteroceptive signals (e.g., by relying on visual, tactile and olfactory cues). While questionnaires are available for assessing interoception, there are no validated self-report instruments for measuring bodily exterception. To fill this gap, we performed three studies to develop and validate a novel scale designed to assess bodily self-consciousness based on the processing of exteroceptive bodily signals. Exploratory factor analysis (Study 1, N = 302) led to an 18-item questionnaire comprised of four factors. We called this instrument Exteroceptive Body Awareness questionnaire (EBA-q). Confirmatory factor analysis (Study 2, N = 184) run on a second sample showed an acceptable fit for a bifactor model, suggesting researchers may use the questionnaire as a unidimensional scale reflecting exteroceptive bodily self-consciousness, or use each of its four sub-scales, reflecting "visuo-tactile body awareness", "spatial coordination", "awareness of body changes" and "awareness of clothing fit". Overall EBA-q showed good internal consistency. Convergent and divergent validity were assessed via cross-validation with existing body awareness questionnaires (Study 3, N = 366) and behavioral measures (Study 3, N = 64) of exteroceptive and interoceptive bodily self-consciousness. Research applications are discussed within a multi-faceted model of exteroception and interoception as distinct, but at the same time interconnected, dimensions of bodily self-consciousness.

Psychometric properties of an Arabic translation of the multidimensional assessment of interoceptive awareness (MAIA-2) questionnaire in a non-clinical sample of Arabic-speaking adults

BACKGROUND

Interoception refers to processes through which the nervous system identifies, analyzes, and integrates the information generated by the physiological state of the body (e.g., from internal organs such as the stomach, heart, or lungs). Despite its potential interest for clinical research and its wide use globally, no Arabic adaptation and validation of the Multidimensional Assessment of Interoceptive Awareness (MAIA-2) questionnaire exists to date. The goal of this study was to examine the psychometric properties of an Arabic translation of the MAIA-2 in a sample of Arabic-speaking community adults from Lebanon. We hypothesized that the Arabic version of the MAIA-2 would yield adequate internal consistency coefficients; the 8-factor structure model would show a good fit to our data, with measurement invariance and good convergent validity.

METHOD

The Arabic adaptation of the MAIA-2 was developed using the forward-backward translation method. A non-clinical sample of Arabic-speaking adults (n = 359, 59.9% females, mean age = 22.75 years (SD = 7.04)) took part of this validation study. To check if the model was adequate, several fit indices were calculated: the normed model chi-square (χ²/df), the Steiger-Lind root mean square error of approximation (RMSEA), the Tucker-Lewis Index (TLI) and the comparative fit index (CFI). Values ≤ 3 for χ²/df, and ≤ 0.08 for RMSEA, and 0.90 for CFI and TLI indicate good fit of the model to the data.

RESULTS

Confirmatory Factor Analyses corroborated the validity of the original 8-factor structure of the MAIA-2 [χ2/df = 1603.86/601 = 2.67, RMSEA = 0.068 (90% CI 0.064, 0.072), SRMR = 0.058, CFI = 0.903, TLI = 0.892]. Reliability estimates in our sample revealed good internal consistency, with McDonald's ω coefficients for the subscales ranging from 0.86 to 0.93. Our analyses also revealed measurement invariance of the Arabic MAIA-2 for gender. No statistically significant difference between men and women in all dimensions, except for the not worrying and attention regulation subscales where men scored significantly higher than women. Finally, the Arabic MAIA-2 dimensions showed positive correlations with the intuitive eating dimension "Reliance on Hunger and Satiety Cues", thus providing support for convergent validity.

CONCLUSION

We contribute the literature by providing the first Arabic adaptation and validation of a measure assessing the multidimensional construct of self-reported interoception. The Arabic MAIA-2 demonstrated good psychometric properties. We thus preliminarily recommend its use to measure the interoceptive awareness construct among Arabic-speaking communities worldwide.

Interoceptive awareness in a Norwegian population: psychometric properties of the Multidimensional Assessment of Interoceptive Awareness (MAIA) 2

BACKGROUND

Interoception plays a vital role in human cognition and emotion and is an increasingly important part of clinical studies of mind-body approaches and mental health. Interoceptive awareness (IA) encompasses numerous mind-body components and can be assessed by employing a self-report measure such as the Multidimensional Assessment of Interoceptive Awareness (MAIA), which has been adapted and validated across several countries and is used in experimental and clinical settings. In this study, the MAIA-2, which was developed due to the psychometric shortages of MAIA, was thoroughly translated, and its psychometric features were examined in a sample of 306 Norwegian-speaking participants (81% females, ages 16 through 66 plus).

METHODS

The participants completed the MAIA-2 Norwegian version (MAIA-2-N) and the COOP/WONCA Functional Assessment Charts measuring psychological, physical, and overall health. The following psychometric qualities of the MAIA-2 were investigated: factor structure, internal consistency, and the moderating role of gender.

RESULTS

Confirmatory Factor Analysis (CFA) revealed that an 8-factor model of MAIA-2-N provided the best fit. Also, a bifactor model revealed a proper fit. Good internal consistency and a moderating role of gender, age, and education on the relationships between certain MAIA-2-N factors and health were observed.

CONCLUSIONS

The MAIA-2-N is an adequate measure of IA in Norwegian-speaking individuals. The factor-structure corresponds with the original MAIA-2 and it shows good internal consistency. Some moderating effects of gender were observed, particularly related to the relationship between IA and physical and psychological state, with the physical state/fitness more closely linked to IA in males and psychological state in females.

Visual respiratory biofeedback to improve visuospatial cognition and cardiac interoception in migraineurs: a study protocol for a randomized controlled trial

Objectives

Migraine is a complex neurological disorder that typically presents with unilateral cephalgia associated with cognitive impairment and reduced interoception. These symptoms result in socio-economic repercussions due to reduced productivity, efficiency, and work performance. Therefore, along with headache management, improving cognition and interoception should also be significant therapeutic targets to effectively manage migraine. To achieve this, we propose to explore the role of a yoga-based visual respiratory biofeedback (VRB) as a possible therapeutic strategy.

Methods and analysis

At least 64 participants will be recruited for the trial after screening for eligibility criteria, using the migraine screening questionnaire and Montreal cognitive assessment test. They will be randomly allocated (1:1) to either the experimental group receiving a 20-min session of yoga-based VRB or the control group who will be asked to watch a documentary film for the same duration. Visuospatial cognition will be assessed by the Corsi block-tapping task, and cardiac interoceptive accuracy will be assessed by the heartbeat counting task at baseline and immediately after the intervention. Based on the distribution and variance of the data obtained, analysis will be conducted based on linear mixed models using SPSS version 28.0.1.0, with a two-sided p-value of < 0.05 considered to be statistically significant.

Discussion

To the best of our knowledge, this is the first study to design and assess the effects of yoga-based biofeedback therapy on cognition and cardiac interoception in migraineurs. Furthermore, we postulated that pranayama's therapeutic effects might be enhanced by using visual yogic respiratory biofeedback. Considering the socio-economic burden of migraine, if found effective, VRB investigated in the trial could be considered as a therapeutic strategy.

Clinical trial registration

ClinicalTrials.gov CTRI, CTRI/2023/03/050430.

Multidimensional assessment of anticipated and experienced interoceptive states

As the sense of the body's internal state, interoception represents the afferent component of the brain-body feedback loop essential for linking internal sensation with body regulation, thereby minimizing erroneous feedback and maintaining homeostasis. The anticipation of potential future interoceptive states enables organisms to take regulatory actions to meet demands before they arise, and alterations of anticipation have been implicated in the pathophysiology of medical and psychiatric conditions. However, laboratory approaches operationalizing the anticipation of interoceptive states are missing. Therefore, we developed two interoceptive awareness paradigms, the Accuracy of Interoceptive Anticipation paradigm, and the Interoceptive Discrepancy paradigm, which we tested in 52 healthy participants on two sensory modalities: nociception and respiroception. Ten participants took part in a retest. The Accuracy of Interoceptive Anticipation paradigm focused on assessing how individuals anticipate and experience interoceptive stimuli of varying strengths. The Interoceptive Discrepancy paradigm extended this measure by manipulating previously learned expectations to induce discrepancies between anticipated and experienced stimuli. We found that anticipation and experience ratings successfully related to stimulus strength in both paradigms and modalities and were stable between test-retest. Furthermore, the Interoceptive Discrepancy paradigm successfully induced the expected discrepancies between anticipation and experience conditions, and discrepancy values were correlated across sensory modalities. Thus, both paradigms are valid and reliable tools for assessing the anticipation of future interoceptive states, and the Interoceptive Discrepancy paradigm is additionally suited to evaluate discrepancy awareness.

Revisiting uncertainty as a felt sense of unsafety: The somatic error theory of intolerance of uncertainty

Intolerance of uncertainty (IU) has gained widespread interest as a construct of broad interest from both transdiagnostic and trans-situational perspectives. We have approached this article inspired by the curiosity, clinical observation, consideration of different theoretical perspectives, speculation, optimism and indeed fun that can be seen in S. J. Rachman's work. We address some of what we know about IU before considering one way of conceptualizing IU from the standpoint of a felt sense or embodied experience. In the first part, we start with Woody and Rachman's (1994) observations of people with GAD. Second, we consider some key findings from the literature. Third, we consider two important perspectives on uncertainty, namely, Brosschot et al.'s (2016, 2018) influential Generalized Unsafety Theory of Stress and uncertainty as an emotion. In the second part, backing our clinical hunch about the importance of the felt sense of uncertainty, we consider IU from the perspective of interoception and the somatic error theory of anxiety (Khalsa & Feinstein, 2018). We propose the somatic error theory of intolerance of uncertainty, which places the experience of uncertainty at the heart of our understanding of intolerance of uncertainty. This is followed by predictions, unresolved questions, and potential clinical implications. Finally, we revisit Woody and Rachman's (1994) suggestions for treatment as internalizing "a sense of safety in a range of circumstances (p. 750)" and update this from the perspective of the felt sense of uncertainty. We finish by suggesting that uncertainty can be tolerated, perhaps accepted, and even embraced.

A Primer on Interoception and its Importance in Psychiatry

Interoception is the perception of signals from inside the body. It plays a significant role in the nervous, cardiovascular, respiratory, gastrointestinal, genitourinary, and endocrine systems. It is also closely related to the autonomic nervous system and inflammatory pathways and plays a significant role in our optimal functioning. Recently, interoception has gained more attention in neuropsychiatric research. Anatomical and physiological aspects of interoception like relevant brain areas, the role of the vagus nerve, and the autonomic nervous system are gradually being understood. Different facets of interoception like interoceptive attention, detection, magnitude, discrimination, accuracy, awareness, and appraisal have been proposed and their assessments and importance are being evaluated. Further, interoception is often dysregulated or abnormal in psychiatric disorders. It has been implicated in the psychopathology, etiopathogenesis, clinical features and treatment of mood, anxiety, psychotic, personality and addiction-related disorders. This narrative review attempts to provide a nuanced understanding of the pathway(s), components, functions, assessments, and problems of interoception and will help us to detect its disturbances and evaluate its impact on psychiatric disorders, leading to a better perspective and management. This will also advance interoception-related research.

Development of a Participation Focused Measure of Interoception for Adults

Interoception is awareness of one's own internal bodily states. Currently, no participation-based measure of interoception exists. The purpose of this study was to identify items with adequate psychometric properties for a participation-based interoceptive measure grounded in Dunn's Sensory Processing Framework named the Sensory Profile: Interoception (SPI). Using a cross-sectional psychometric design, internal consistency was examined by calculating Cronbach's alpha for each of the four subscales of the SPI. Concurrent validity was studied using Pearson Product Moment Correlations to identify relationships between the SPI and the Adolescent Adult Sensory Profile (A/ASP) subscales. Interoception items correlating most strongly with their intended subscale were identified, maintaining 70 of the original 101 items (N = 55). The resulting subscales (sensitivity, avoiding, registration, and seeking) had good internal consistency (α = .63-.88) and correlated moderately with the corresponding A/ASP subscale. The findings provide preliminary support for the SPI's internal consistency and concurrent validity.

Central control of cardiac activity as assessed by intra-cerebral recordings and stimulations

Some of the most important integrative control centers for the autonomic nervous system are located in the brainstem and the hypothalamus. However, growing recent neuroimaging evidence support that a set of cortical regions, named the central autonomic network (CAN), is involved in autonomic control and seems to play a major role in continuous autonomic cardiac adjustments to high-level emotional, cognitive or sensorimotor cortical activities. Intracranial explorations during stereo-electroencephalography (SEEG) offer a unique opportunity to address the question of the brain regions involved in heart-brain interaction, by studying: (i) direct cardiac effects produced by the electrical stimulation of specific brain areas; (ii) epileptic seizures inducing cardiac modifications; (iii) cortical regions involved in cardiac interoception and source of cardiac evoked potentials. In this review, we detail the available data assessing cardiac central autonomic regulation using SEEG, address the strengths and also the limitations of this technique in this context, and discuss perspectives. The main cortical regions that emerge from SEEG studies as being involved in cardiac autonomic control are the insula and regions belonging to the limbic system: the amygdala, the hippocampus, and the anterior and mid-cingulate. Although many questions remain, SEEG studies have already demonstrated afferent and efferent interactions between the CAN and the heart. Future studies in SEEG should integrate these afferent and efferent dimensions as well as their interaction with other cortical networks to better understand the functional heart-brain interaction.

Pilot Study About the Effects of the Soma Experiencing Motion (Soma e-Motion) Program on Interoceptive Awareness and Self-Compassion

OBJECTIVE

The purpose of this study was to examine the effects of the Soma experiencing motion (Soma e-motion) program on interoceptive awareness and self-compassion among novices.

METHODS

A total of 19 adults (clinical group=9, non-clinical group=10) participated in the intervention. Psychological and physical changes after program were qualitatively analyzed using in-depth interviews. The Korean Multidimensional Assessment of Interoceptive Awareness (K-MAIA) and the Korean version of the Self-Compassion Scale (K-SCS) were used as quantitative measures.

RESULTS

The non-clinical group showed statistically significant differences in the K-MAIA scores (z=-2.805, p<0.01) and K-SCS scores (z=-2.191, p<0.05); however, the clinical group showed no significant differences (K-MAIA: z=-0.652, p>0.05; K-SCS: z=-0.178, p>0.05). According to the in-depth interviews, the results of the qualitative analysis were categorized into five dimensions (psychological and emotional, physical, cognitive, behavioral, and aspects participants found challenging and needs improvement).

CONCLUSION

The Soma e-motion program was feasible for improving interoceptive awareness and self-compassion in the non-clinical group. However, further research is needed to investigate the clinical efficacy of the Soma e-motion program for clinical group.

Disinhibition augments thirst perception from two dehydrating stimuli in men

Physiological systems controlling water and energy ingestion are coordinated. Whether maladaptive eating behavior and appetite for water are linked is unknown. Thus, we sought to investigate the association between maladaptive eating and both thirst and water drinking behavior with two dehydrating conditions. Twenty-two lean men and 20 men with obesity (mean age 32.3 ± 8.4 years and 30.0 ± 11.1 years, respectively) completed the Three-Factor Eating Questionnaire (TFEQ) and Gormally Binge Eating Scale. On separate days, volunteers were dehydrated by a 2-h hypertonic saline infusion and a 24-h water deprivation, and thirst was measured on a 100-mm visual analogue scale (VAS) during each procedure. After each dehydrating condition, ad libitum water intake was measured. In the saline infusion, higher Disinhibition on the TFEQ was associated with thirst in the lean group (β = 4.2 mm VAS, p = 0.03) but not in the group with obesity (p = 0.51). In the water-deprivation condition, higher Disinhibition was also associated with thirst in the lean group (β = 5.6 mm VAS, p = 0.01) with the strength of relationship being 3.5-fold stronger than that observed in the group with obesity (β = 1.6 mm VAS, p = 0.0003). Hunger, Restraint, and binge-eating scores were not associated with thirst in either dehydrating condition (all p > 0.05). Maladaptive eating behaviors were not associated with ad libitum water intake (all p > 0.05). Disinhibition is associated with higher thirst perception in healthy weight individuals and may be attenuated in obesity. The characteristics of disinhibition which typically includes a heightened readiness to eat, may reflect a more general phenotype that also reflects a readiness to drink.

Neural networks involved in nausea in adult humans: A systematic review

Nausea is a common clinical symptom, poorly managed with anti-emetic drugs. To identify potential brain regions which may be therapeutic targets we systematically reviewed brain imaging in subjects reporting nausea. The systematic review followed PRISMA statements with methodological quality (MINORS) and risk of bias (ROBINS-I) assessed. Irrespective of the nauseagenic stimulus the common (but not only) cortical structures activated were the inferior frontal gyrus (IFG), the anterior cingulate cortex (ACC) and the anterior insula (AIns) with some evidence for lateralization (Left-IFG, Right-AIns, Right-ACC). Basal ganglia structures (e.g., putamen) were also consistently activated. Inactivation was rarely reported but occurred mainly in the cerebellum and occipital lobe. During nausea, functional connectivity increased, mainly between the posterior and mid- cingulate cortex. Limitations include, a paucity of studies and stimuli, subject demographics, inconsistent definition and measurement of nausea. Structures implicated in nausea are discussed in the context of knowledge of central pathways for interoception, emotion and autonomic control. Comparisons are made between nausea and other aversive sensations as multimodal aversive conscious experiences.

Physiological reactivity at rest and in response to social or emotional stimuli after a traumatic brain injury: A systematic review

Numerous studies have shown that alterations in physiological reactivity (PR) after traumatic brain injury (TBI) are possibly associated with emotional deficits. We conducted a systematic review of these studies that evaluated PR in adults with moderate-to-severe TBI, either at rest or in response to emotional, stressful, or social stimuli. We focused on the most common measures of physiological response, including heart rate (HR), heart rate variability (HRV), respiratory sinus arrhythmia (RSA), electrodermal activity (EDA), salivary cortisol, facial electromyography (EMG), and blink reflex.

Methods

A systematic literature search was conducted across six databases (PsycINFO, Psycarticles, SciencDirect, Cochrane Library, PubMed, and Scopus). The search returned 286 articles and 18 studies met the inclusion criteria.

Results

Discrepancies were observed according to the type of physiological measure. Reduced physiological responses in patients with TBI have been reported in most EDA studies, which were also overrepresented in the review. In terms of facial EMG, patients with TBI appear to exhibit reduced activity of the corrugator muscle and diminished blink reflex, while in most studies, zygomaticus contraction did not show significant differences between TBI and controls. Interestingly, most studies measuring cardiac activity did not find significant differences between TBI and controls. Finally, one study measured salivary cortisol levels and reported no difference between patients with TBI and controls.

Conclusion

Although disturbed EDA responses were frequently reported in patients with TBI, other measures did not consistently indicate an impairment in PR. These discrepancies could be due to the lesion pattern resulting from TBI, which could affect the PR to aversive stimuli. In addition, methodological differences concerning the measurements and their standardization as well as the characteristics of the patients may also be involved in these discrepancies. We propose methodological recommendations for the use of multiple and simultaneous PR measurements and standardization. Future research should converge toward a common methodology in terms of physiological data analysis to improve inter-study comparisons.

Hair cortisol reduction and social integration enhancement after a mindfulness-based intervention in children

BACKGROUND

Over recent decades, chronic stress at an early age has become a worrying health problem in children. We seek to evaluate an intervention involving mindfulness-based practices and prosocial activities in 7- to 8-year-old children.

METHODS

Stress levels were determined using hair cortisol concentration (HCC), and social integration was measured by means of a sociogram. The program had previously proven to be effective in decreasing salivary cortisol levels and in favouring social integration in children. A total of 35 children participated in the study: 18 constituted the intervention group and 17 the wait-list group. In both groups, HCC and social integration were evaluated before and after the intervention conducted throughout an entire school year.

RESULTS

The experimental group showed a significant reduction in HCC, as well as significant enhancement of social integration levels, whereas no changes were observed in the wait-list group.

CONCLUSIONS

This is the first research to show that HCC, a reliable neuroendocrine indicator, decreased as a result of a mindfulness-based program. This successful outcome adds new evidence to previous findings regarding the reduction of chronic stress in children following participation in this program.

The Role of the Skin in Interoception: A Neglected Organ?

In the past 2 decades, interoception has received increasing attention in the fields of psychology and cognitive science, as well as neuroscience and physiology. A plethora of studies adopted the perception of cardiac signals as a proxy for interoception. However, recent findings have cast doubt on the methodological and intrinsic validity of the tasks used thus far. Therefore, there is an ongoing effort to improve the existing cardiac interoceptive tasks and to identify novel channels to target the perception of the physiological state of the body. Amid such scientific abundancy, one could question whether the field has been partially neglecting one of our widest organs in terms of dimensions and functions: the skin. According to some views grounded on anatomical and physiological evidence, skin-mediated signals such as affective touch, pain, and temperature have been redefined as interoceptive. However, there is no agreement in this regard. Here, we discuss some of the anatomical, physiological, and experimental arguments supporting the scientific study of interoception by means of skin-mediated signals. We argue that more attention should be paid to the skin as a sensory organ that monitors the bodily physiological state and further propose thermosensation as a particularly attractive model of skin-mediated interoception.

A rationale for considering heart/brain axis control in neuropsychiatric disease

Neuropsychiatric diseases (NPD) represent a significant global disease burden necessitating innovative approaches to pathogenic understanding, biomarker identification and therapeutic strategy. Emerging evidence implicates heart/brain axis malfunction in NPD etiology, particularly via the autonomic nervous system (ANS) and brain central autonomic network (CAN) interaction. This heart/brain inter-relationship harbors potentially novel NPD diagnosis and treatment avenues. Nevertheless, the lack of multidisciplinary clinical approaches as well as a limited appreciation of molecular underpinnings has stymied progress. Large-scale preclinical multi-systemic functional data can therefore provide supplementary insight into CAN and ANS interaction. We here present an overview of the heart/brain axis in NPD and establish a unique rationale for utilizing a preclinical cardiovascular disease risk gene set to glean insights into heart/brain axis control in NPD. With a top-down approach focusing on genes influencing electrocardiogram ANS function, we combined hierarchical clustering of corresponding regional CAN expression data and functional enrichment analysis to reveal known and novel molecular insights into CAN and NPD. Through ‘support vector machine’ inquiries for classification and literature validation, we further pinpointed the top 32 genes highly expressed in CAN brain structures altering both heart rate/heart rate variability (HRV) and behavior. Our observations underscore the potential of HRV/hyperactivity behavior as endophenotypes for multimodal disease biomarker identification to index aberrant executive brain functioning with relevance for NPD. This work heralds the potential of large-scale preclinical functional genetic data for understanding CAN/ANS control and introduces a stepwise design leveraging preclinical data to unearth novel heart/brain axis control genes in NPD.

Interoceptive sensibility and body satisfaction in pregnant and non-pregnant women with and without children

Pregnancy is a time of great physical and psychological change. As well as prominent changes in the external appearance of the body, such as the baby bump, there are also substantial changes taking place within the body. Our awareness of, and attention towards, internal bodily signals (interoception) is thought to have a direct impact on how we feel about our bodies. Therefore, understanding how our experience of these interoceptive signals might change during pregnancy may have important implications for maternal wellbeing. This study examined body satisfaction and interoceptive sensibility (subjective experience of interoception) in pregnant and non-pregnant women with and without children. Feelings towards pregnancy-specific changes in body satisfaction and interoceptive sensibility were also examined in women in their first pregnancy (primigravida) and subsequent pregnancies (multigravida). It was found that pregnancy did not directly impact levels of body satisfaction, instead pregnant and non-pregnant women with children reported less satisfaction with their bodies compared to those without children. Primigravida women were more satisfied with the appearance of pregnancy specific bodily changes compared to multigravida women. Interestingly, these differences in body satisfaction in those with children (pregnant and non-pregnant) were mediated by the extent to which women trusted their bodies (measure of interoceptive sensibility). All other pregnancy related changes in interoceptive sensibility and body satisfaction were either non-significant or had small effect sizes. These results may suggest body trust as an important factor to support during the transition to parenthood in order to improve body satisfaction in mothers.

The Use of Kinesthetic Empathy with Adults Living with Treatment Resistant Depression: A Survey Study

Dance/movement therapy is an embodied healing practice which has been found to foster recovery from depression and boost quality of life. Although kinesthetic empathy holds great potential for addressing emotional dysregulation, it is an under-utilized dance/movement therapy intervention in health optimization, especially in adults living with treatment-resistant depression. The aim of this study was to collect data from dance/movement therapist on how they use kinesthetic empathy to foster self-regulation in adults living with treatment-resistant depression. A survey design was used to obtain this data. Eight dance/movement therapists (practicing in India, Philippines, Barbados, and the United States of America) were recruited. The participant demographics of the survey challenges the centrality of master’s level trained dance/movement therapists primarily practicing in Eurocentric cultures. The survey included open answer questions, and responses received were grouped into four categories: (i) dance/movement therapists’ rationale for using kinesthetic empathy (ii) therapist-described client responses to kinesthetic empathy, (iii) changes in self-regulation patterns of clients, and (iv) potential links between employing kinesthetic empathy as an intervention and witnessing emotional regulation in clients. Overall, kinesthetic empathy was described as a core part of the participants’ dance/movement therapy practice with this population. The identified client responses to kinesthetic empathy were categorized based on deWitte’s et al. (Frontiers in Psychology, 2021) therapeutic factors of change. ‘Observable client responses’, such as, use of metaphors, verbalization of body sensations and engaging in mirroring were categorized under specific therapeutic factors of dance/movement therapy. Alternatively, ‘emotionally felt client responses’ such as, increase in safety and trust within the therapeutic alliance were categorized under both ‘specific’ and ‘mixed-type’ factors based on the model. Finally, this article discusses movement interventions that may be incorporated by dance/movement therapists while working with this population. Further research is required to identify the long-term effect/s of kinesthetic empathy as an intentional intervention to foster self-regulation in adults living with treatment-resistant depression.

Interoceptive accuracy and bias in somatic symptom disorder, illness anxiety disorder, and functional syndromes: A systematic review and meta-analysis

Somatic symptom disorder, illness anxiety disorder, and functional syndromes are characterized by burdensome preoccupation with somatic symptoms. Etiological models propose either increased interoceptive accuracy through hypervigilance to the body, or decreased and biased interoception through top-down predictions about sensory events. This systematic review and meta-analysis summarizes findings of 68 studies examining interoceptive accuracy and 8 studies examining response biases in clinical or non-clinical groups. Analyses yielded a medium population effect size for decreased interoceptive accuracy in functional syndromes, but no observable effect in somatic symptom disorder and illness anxiety disorder. The overall effect size was highly heterogeneous. Regarding response bias, there was a small significant effect in somatic symptom disorder and illness anxiety disorder. Our findings strengthen the notion of top-down factors that result in biased rather than accurate perception of body signals in somatic symptom disorder and illness anxiety disorder.

The relationship between interoception and agency and its modulation by heartbeats: an exploratory study

Interoception, the sense of the internal physiological state of the body, theoretically underpins aspects of self-representation. Experimental studies link feelings of body ownership to interoceptive perception, yet few studies have tested for association between the sense of agency and interoceptive processing. Here, we combined an intentional binding paradigm with cardiac measures of interoceptive processing (behavioural performance on a heartbeat discrimination task, and effects of timing within the cardiac cycle) in twenty-six non-clinical participants as an exploratory study. We found performance accuracy on the heartbeat discrimination task correlated positively with the intentional binding effect, an index of sense of agency (β = 0.832, p = 0.005), even after controlling for effects of age, sex, educational level, heart rate, heart rate variability and time accuracy. The intentional binding effect was enhanced during cardiac systole (compared to diastole) in individuals with greater heartbeat discrimination accuracy (β = 0.640, p = 0.047). These findings support the proposal that interoception contributes to mechanisms underlying the emergence of sense of agency.

Spatial-topographic nestedness of interoceptive regions within the networks of decision making and emotion regulation: Combining ALE meta-analysis and MACM analysis

Prominent theories propose that interoception modulates our behavioral and emotional responses involving decision-making and emotion regulation. Are the regions implicated in interoception also spatially related to and possibly nested within the networks of decision making and emotion regulation? Addressing this question, we performed three meta-analyses of functional magnetic resonance imaging studies to identify the regions that are commonly activated by the three domains using activation likelihood estimation (ALE). Additionally, we assessed the coactivation pattern of identified common regions using meta-analytic connectivity modeling (MACM). The results showed major overlaps of interoception with both decision making and emotion regulation in specifically the right dorsal anterior insula. The pairwise contrast analyses confirmed this finding and revealed conjunction-based activities in decision making and emotion regulation in the dorsal anterior cingulate cortex (dACC). MACM based on the identified insula revealed a widespread convergent coactivation pattern with the left anterior insula, dACC, and bilateral thalamus which, together, constitute the salience network. Among these co-activated regions, bilateral insula and the dACC were shared among all three domains. These results suggest that the regions mediating interoception including intero-exteroceptive integration and salience attribution are contained and thus spatially nested within the more extensive networks recruited during decision making and emotion regulation.

Interoception: A Multi-Sensory Foundation of Participation in Daily Life

The purpose of this article is to examine evidence that broadens the clinical perspective on interoception as an imperative consideration for individuals with mental health and sensory processing challenges. The central supposition is that interoception is broader than just signals from the viscera. Rather, interoception refers to perceptions of bodily signals and bodily states that construct a subjective representation of the experience. These representations are then utilized for categorizing the sensory attributes and constructing meaning. Thus, this updated conceptualization presents interoception as a complex multidimensional system, with bidirectional features. The interplay between the brain and the body is necessary to maintain homeostasis as well as respond adaptively to the changes in one's internal and external environment. As a sensory capacity, interoceptive information must be processed and interpreted before it can be integrated into a personal experiential history. Interoception supports both body and mental functions and as such, interoceptive processes support health and wellness by establishing a felt sense of psychological and physiological safety that is foundational to meaningful participation in life. The information presented in this article is central to the pursuit of evidence-based best practices for any professional wishing to integrate consideration of interoception into their clinical practice.

Construct Validity of the Sensory Profile Interoception Scale: Measuring Sensory Processing in Everyday Life

Scholars and providers are coming to realize that one’s ability to notice and respond to internal body sensations (i.e., interoception) contributes to an overall sense of wellbeing. Research has demonstrated a relationship between interoceptive awareness and anxiety, for example. Currently, however, tools for evaluating one’s interoception lack the conceptual foundation and clarity necessary to identify everyday behaviors that specifically reflect interoceptive awareness. Unlike existing interoceptive measures, the Sensory Profile Interoception (SPI) scale is participation-based and grounded in Dunn’s Sensory Processing framework. In this study we investigated concurrent validity by correlating the SPI with the Adolescent/Adult Sensory Profile (A/ASP); we investigated construct validity by correlating the SPI with the Perth Alexithymia Scale (PAS), the Body Awareness Scale (BAS), and the State-Trait Anxiety Inventory (STAI). Using the REDCAP online platform, 74 college-aged participants completed the measures. Using Spearman rank order correlations there were statistically significant relationships between the corresponding sensory pattern subscales on SPI and A/ASP (r = 0.277 to r = 0.582). The PAS was only weakly related to the registration subscale of the SPI (r = 0.260). The BAS had significant relationships with seeking and avoiding on the SPI (r = 0.496 and r = 0.385). The STAI had significant relationships with sensitivity and registrations of the SPI (r = 0.266 and r = 0.361 for state; r = 0.403 and r = 0.321 for trait). Taken together, these findings provide evidence of construct validity of the SPI to identify participation patterns associated with both high and low interoception. With the more precise information the SPI provides, professionals can design tailored interventions to support everyday life goals and researchers can study interoception within authentic activities.

Osteopathic Manipulative Treatment Regulates Autonomic Markers in Preterm Infants: A Randomized Clinical Trial

Osteopathic manipulative treatment (OMT) has been found to be effective in the context of premature infants. Nonetheless, no studies have investigated the immediate effects of OMT on heart rate variability (HRV). As altered HRV reflects poor or worsening newborn’s clinical conditions and neurodevelopment, should OMT improve HRV fluctuations, it could become a relevant intervention for improving the care of preterm newborns. Therefore, this study aimed to evaluate whether OMT could affect HRV. The study was carried out at the Buzzi Hospital in Milan. From the neonatal intensive care unit, ninety-six preterm infants (41 males) were enrolled and were randomly assigned to one of two treatment groups: OMT or Static Touch. The infants were born at 33.5 weeks (±4.3) and had a mean birth weight of 2067 g (±929). The study had as primary outcome the change in the beat-to-beat variance in heart rate measured through root mean square of consecutive RR interval differences (RMSSD); other metrics were used as secondary and exploratory analyses. Despite the lack of statistically significant results regarding the primary outcomeand some study limitations, compared to static touch, OMT seemed to favor a parasympathetic modulation and improved HRV, which could reflect improvement in newborn’s clinical conditions and development.

The role of interoception in the overlap between eating disorders and autism: Methodological considerations

Significant comorbidity has been demonstrated between feeding and eating disorders and autism. Atypical interoception (perception of bodily signals) may, at least in part, be responsible for this association, as it has been implicated in the aetiology of both conditions. However, significant methodological limitations are impeding progress in this area. This paper provides a brief overview of how interoception has been linked to autism and feeding and eating disorders in both adolescent and adult populations before identifying several issues with current measures of interoception. We suggest that methodological issues may be contributing to the inconsistency in the empirical literature, and provide suggestions for future research.

Atypical interoception is linked to both feeding and eating disorders, and autism and may contribute to the comorbidity between the two.

Existing measures of interoception across cardiac, gastric and respiratory domains are severely limited.

Novel and better‐validated measures of interoception will allow us to better understand the clinical potential of interoceptive training.

Brain Response to a Knee Proprioception Task Among Persons With Anterior Cruciate Ligament Reconstruction and Controls

Knee proprioception deficits and neuroplasticity have been indicated following injury to the anterior cruciate ligament (ACL). Evidence is, however, scarce regarding brain response to knee proprioception tasks and the impact of ACL injury. This study aimed to identify brain regions associated with the proprioceptive sense of joint position at the knee and whether the related brain response of individuals with ACL reconstruction differed from that of asymptomatic controls. Twenty-one persons with unilateral ACL reconstruction (mean 23 months post-surgery) of either the right (n = 10) or left (n = 11) knee, as well as 19 controls (CTRL) matched for sex, age, height, weight and current activity level, performed a knee joint position sense (JPS) test during simultaneous functional magnetic resonance imaging (fMRI). Integrated motion capture provided real-time knee kinematics to activate test instructions, as well as accurate knee angles for JPS outcomes. Recruited brain regions during knee angle reproduction included somatosensory cortices, prefrontal cortex and insula. Neither brain response nor JPS errors differed between groups, but across groups significant correlations revealed that greater errors were associated with greater ipsilateral response in the anterior cingulate (r = 0.476, P = 0.009), supramarginal gyrus (r = 0.395, P = 0.034) and insula (r = 0.474, P = 0.008). This is the first study to capture brain response using fMRI in relation to quantifiable knee JPS. Activated brain regions have previously been associated with sensorimotor processes, body schema and interoception. Our innovative paradigm can help to guide future research investigating brain response to lower limb proprioception.

On the body-mind nexus in chronic musculoskeletal pain: A scoping review

BACKGROUND AND OBJECTIVE

Bodily experience disturbances are frequent among chronic musculoskeletal pain patients and associated with important pain-related psychosocial outcomes (e.g., disability, quality of life). However, the relationship between bodily experience and the psychological dimensions of chronic pain (e.g., affective, cognitive) has only recently garnered attention. This scoping review aimed to identify trends and gaps in research on the nexus between body awareness, body image, and body schema, and psychological processes/outcomes in adults with chronic musculoskeletal pain to inform future directions for research and practice.

DATABASES AND DATA TREATMENT

This study was guided by Arksey and O'Malley's guidelines and PRISMA-ScR recommendations. Keywords related to body awareness/body image/body schema and pain were searched on PsycInfo and PubMed from database inception until February 16, 2021; 2045 articles were screened, and 41 met the inclusion criteria (i.e., primary quantitative studies investigating body awareness/body image/body schema in relation to pain-related psychological outcomes/processes in chronic musculoskeletal pain).

RESULTS

The referred bodily experience constructs have been inconsistently defined. Body awareness was the most investigated construct, with consistent operationalization strategies. The links between body schema/body image and pain-related psychological processes/outcomes are still under-investigated. Most studies examined the role of bodily experience as a correlate/predictor of psychological outcomes/processes; overall, a better relationship with one's own body was associated with better pain-related psychological outcomes/processes.

CONCLUSIONS

Our findings emphasize the relevance of further investigating body-mind relations in musculoskeletal pain and the development of therapies designed to improve the bodily experience within multidisciplinary treatment programs. Suggestions for future research are discussed.

Past and Future Explanations for Depersonalization and Derealization Disorder: A Role for Predictive Coding

Depersonalization (DP) and derealization (DR) refer to states of dissociation in which one feels a sense of alienation in relation to one's self and environment, respectively. Whilst transient episodes often diminish without treatment, chronic experiences of DP and DR may last for years, with common treatments lacking a strong evidence base for their efficacy. We propose a theoretical explanation of DP and DR based on interoceptive predictive coding, and discuss how transient experiences of DP and DR may be induced in the non-clinical population using virtual reality. Further, we review the use of heartbeat evoked potentials in detecting the neural correlates of DP and DR allowing for an objective measure of these experiences in the non-clinical population. Finally, we discuss how the induction and detection of transient experiences of DP and DR in the non-clinical population could shed light on how the brain constructs one's sense of self and reality.