Changes in interoceptive accuracy related to emotional interference in somatic symptom disorder.

OBJECTIVE: The somatic symptom disorder (SSD) is characterized by one or more distressing or disabling somatic symptoms accompanied by an excessive amount of time, energy and emotion related to the symptoms. These manifestations of SSD have been linked to alterations in perception and appraisal of bodily signals. We hypothesized that SSD patients would exhibit changes in interoceptive accuracy (IA), particularly when emotional processing is involved. METHODS: Twenty-three patients with SSD and 20 healthy controls were recruited. IA was assessed using the heartbeat perception task. The task was performed in the absence of stimuli as well as in the presence of emotional interference, i.e., photographs of faces with an emotional expression. IA were examined for correlation with measures related to their somatic symptoms, including resting-state heart rate variability (HRV). RESULTS: There was no significant difference in the absolute values of IA between patients with SSD and healthy controls, regardless of the condition. However, the degree of difference in IA without emotional interference and with neutral facial interference was greater in patients with SSD than in healthy controls (p = 0.039). The IA of patients with SSD also showed a significant correlation with low-frequency HRV (p = 0.004) and high-frequency HRV (p = 0.007). CONCLUSION: SSD patients showed more significant changes in IA when neutral facial interference was given. These results suggest that bodily awareness is more affected by emotionally ambiguous stimuli in SSD patients than in healthy controls.

The anterior cingulate cortex is involved in intero-exteroceptive integration for spatial image transformation of the self-body.

Spatial image transformation of the self-body is a fundamental function of visual perspective-taking. Recent research underscores the significance of intero-exteroceptive information integration to construct representations of our embodied self. This raises the intriguing hypothesis that interoceptive processing might be involved in the spatial image transformation of the self-body. To test this hypothesis, the present study used functional magnetic resonance imaging to measure brain activity during an arm laterality judgment (ALJ) task. In this task, participants were tasked with discerning whether the outstretched arm of a human figure, viewed from the front or back, was the right or left hand. The reaction times for the ALJ task proved longer when the stimulus presented orientations of 0°, 90°, and 270° relative to the upright orientation, and when the front view was presented rather than the back view. Reflecting the increased reaction time, increased brain activity was manifested in a cluster centered on the dorsal anterior cingulate cortex (ACC), suggesting that the activation reflects the involvement of an embodied simulation in ALJ. Furthermore, this cluster of brain activity exhibited overlap with regions where the difference in activation between the front and back views positively correlated with the participants' interoceptive sensitivity, as assessed through the heartbeat discrimination task, within the pregenual ACC. These results suggest that the ACC plays an important role in integrating intero-exteroceptive cues to spatially transform the image of our self-body.

Skeletal interoception in osteoarthritis.

The interoception maintains proper physiological conditions and metabolic homeostasis by releasing regulatory signals after perceving changes in the internal state of the organism. Among its various forms, skeletal interoception specifically regulates the metabolic homeostasis of bones. Osteoarthritis (OA) is a complex joint disorder involving cartilage, subchondral bone, and synovium. The subchondral bone undergoes continuous remodeling to adapt to dynamic joint loads. Recent findings highlight that skeletal interoception mediated by aberrant mechanical loads contributes to pathological remodeling of the subchondral bone, resulting in subchondral bone sclerosis in OA. The skeletal interoception is also a potential mechanism for chronic synovial inflammation in OA. In this review, we offer a general overview of interoception, specifically skeletal interoception, subchondral bone microenviroment and the aberrant subchondral remedeling. We also discuss the role of skeletal interoception in abnormal subchondral bone remodeling and synovial inflammation in OA, as well as the potential prospects and challenges in exploring novel OA therapies that target skeletal interoception.

Probing corporeal awareness in women through virtual reality induction of embreathment illusion.

We capitalized on the respiratory bodily illusion that we discovered in a previous study and called 'Embreathment' where we showed that breathing modulates corporeal awareness in men. Despite the relevance of the issue, no such studies are available in women. To bridge this gap, we tested whether the synchronization of avatar-participant respiration patterns influenced females' bodily awareness. We collected cardiac and respiratory interoceptive measures, administered body (dis)satisfaction questionnaires, and tracked participants' menstrual cycles via a mobile app. Our approach allowed us to characterize the 'Embreathment' illusion in women, and explore the relationships between menstrual cycle, interoception and body image. We found that breathing was as crucial as visual appearance in eliciting feelings of ownership and held greater significance than any other cue with respect to body agency in both women and men. Moreover, a positive correlation between menstrual cycle days and body image concerns, and a negative correlation between interoceptive sensibility and body dissatisfaction were found, confirming that women's body dissatisfaction arises during the last days of menstrual cycle and is associated with interoception. These findings have potential implications for corporeal awareness alterations in clinical conditions like eating disorders and schizophrenia.

Effects of mindfulness-based interventions on symptoms and interoception in trauma-related disorders and exposure to traumatic events: Systematic review and meta-analysis.

Interoception is defined as the sense of the internal state of the body. Dysfunctions in interoception are found in several mental disorders, including trauma-related conditions. Mindfulness-Based Interventions (MBIs) have been shown to influence interoceptive processes. Randomised controlled trials (RCTs) have investigated whether MBIs impact symptoms and interoception in patients with trauma-related disorders. We undertook a systematic review and meta-analysis to synthesize these data. We included RCTs with an MBI arm which enrolled adult patients with trauma related-disorders or exposure to a traumatic experience, and addressed changes in interoception and trauma-related symptoms. A random-effects multivariate meta-analytic model was performed to quantify group differences in score change from baseline to follow-up. Twelve studies were included in the systematic review, and eleven in the meta-analysis. Overall, MBIs showed small to moderate positive effects on both interoception and symptoms. Despite a high heterogeneity in results, sensitivity analyses confirmed the robustness of the findings. We conclude that the efficacy of MBIs on trauma-related symptoms and interoception is supported by randomised evidence. However, further research is needed to understand whether changes in interoception might underpin the effectiveness of MBIs in trauma-related disorders.

Exploring the role of neuronal-enriched extracellular vesicle miR-93 and interoception in major depressive disorder.

Major depressive disorder (MDD) is associated with interoceptive processing dysfunctions, but the molecular mechanisms underlying this dysfunction are poorly understood. This study combined brain neuronal-enriched extracellular vesicle (NEEV) technology and serum markers of inflammation and metabolism with Functional Magnetic Resonance Imaging (fMRI) to identify the contribution of gene regulatory pathways, in particular micro-RNA (miR) 93, to interoceptive dysfunction in MDD. Individuals with MDD (n = 41) and healthy comparisons (HC; n = 35) provided blood samples and completed an interoceptive attention task during fMRI. EVs were separated from plasma using a precipitation method. NEEVs were enriched by magnetic streptavidin bead immunocapture utilizing a neural adhesion marker (L1CAM/CD171) biotinylated antibody. The origin of NEEVs was validated with two other neuronal markers - neuronal cell adhesion molecule (NCAM) and ATPase Na+/K+ transporting subunit alpha 3 (ATP1A3). NEEV specificities were confirmed by flow cytometry, western blot, particle size analyzer, and transmission electron microscopy. NEEV small RNAs were purified and sequenced. Results showed that: (1) MDD exhibited lower NEEV miR-93 expression than HC; (2) within MDD but not HC, those individuals with the lowest NEEV miR-93 expression had the highest serum concentrations of interleukin (IL)-1 receptor antagonist, IL-6, tumor necrosis factor, and leptin; and (3) within HC but not MDD, those participants with the highest miR-93 expression showed the strongest bilateral dorsal mid-insula activation during interoceptive versus exteroceptive attention. Since miR-93 is regulated by stress and affects epigenetic modulation by chromatin re-organization, these results suggest that healthy individuals but not MDD participants show an adaptive epigenetic regulation of insular function during interoceptive processing. Future investigations will need to delineate how specific internal and external environmental conditions contribute to miR-93 expression in MDD and what molecular mechanisms alter brain responsivity to body-relevant signals.

mGlu2 and mGlu3 receptor negative allosteric modulators attenuate the interoceptive effects of alcohol in male and female rats.

RATIONALE: The subjective effects of alcohol are associated with alcohol use disorder (AUD) vulnerability and treatment outcomes. The interoceptive effects of alcohol are part of these subjective effects and can be measured in animal models using drug discrimination procedures. The newly developed mGlu2 and mGlu3 negative allosteric modulators (NAMs) are potential therapeutics for AUD and may alter interoceptive sensitivity to alcohol. OBJECTIVES: To determine the effects of mGlu2 and mGlu3 NAMs on the interoceptive effects of alcohol in rats. METHODS: Long-Evans rats were trained to discriminate the interoceptive stimulus effects of alcohol (2.0 g/kg, i.g.) from water using both operant (males only) and Pavlovian (male and female) drug discrimination techniques. Following acquisition training, an alcohol dose-response (0, 0.5, 1.0, 2.0 g/kg) experiment was conducted to confirm stimulus control over behavior. Next, to test the involvement of mGlu2 and mGlu3, rats were pretreated with the mGlu2-NAM (VU6001966; 0, 3, 6, 12 mg/kg, i.p.) or the mGlu3-NAM (VU6010572; 0, 3, 6, 12 mg/kg, i.p.) before alcohol administration (2.0 g/kg, i.g.). RESULTS: In Pavlovian discrimination, male rats showed greater interoceptive sensitivity to 1.0 and 2.0 g/kg alcohol compared to female rats. Both mGlu2-NAM and mGlu3-NAM attenuated the interoceptive effects of alcohol in male and female rats using Pavlovian and operant discrimination. There may be a potential sex difference in response to the mGlu2-NAM at the highest dose tested. CONCLUSIONS: Male rats may be more sensitive to the interoceptive effects of the 2.0 g/kg alcohol training dose compared to female rats. Both mGlu2-and mGlu3-NAM attenuate the interoceptive effects of alcohol in male and female rats. These drugs may have potential for treatment of AUD in part by blunting the subjective effects of alcohol.

Inter-brain entrainment (IBE) during interoception. A multimodal EEG-fNIRS coherence-based hyperscanning approach.

This work examined the impact of interoceptive manipulation and the presence of a shared goal on inter-brain entrainment (IBE) during a motor synchronization task. A multimodal functional Near Infrared Spectroscopy - Electroencephalogram (fNIRS-EEG) system-based hyperscanning approach was applied to 13 dyads performing the motor synchrony task during an interoceptive (focus on the breath) and control condition. Additionally, two version of the motor task-one with and one without a clearly defined common goal-were presented to participants to emphasize the task's collaborative purpose. The multimodal approach was exploited to record the electrophysiological (EEG) cortical oscillation and hemodynamic (oxy-Hb and deoxy-Hb) levels. Results revealed significant correlations between EEG delta, theta, and alpha band and hemodynamic oxy-Hb in the left compared to right hemisphere for the interoceptive confronted with the control condition. This significant EEG/fNIRS IBE correlation was also found for delta and theta band whereas the task was presented with an explicit shared goal confronted with the no-social version. In addition to separate functional connectivity EEG and fNIRS analysis, this study proposed a novel analysis pipeline including statistical tests for examining the coherence between functional connectivity EEG-fNIRS signals within couples. Besides proposing methodological advancements on EEG-fNIRS signals hyperscanning analysis, this research demonstrated that, in dyads undertaking a motor synchronization task, both the interoceptive attention to respiration and an explicit joint intention activate left anterior regions.

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.

Heart rate perception and expectation impact laboratory-induced perceived stress.

Previous studies have shown that the human capacity to gauge one's own physiological state is notoriously flawed. The cause for the mismatch between perceived and physiological stress has not yet been properly identified. In this study, we assumed that cardioceptive accuracy (CAc) is positively associated with cardiovascular reactivity, and CAc and expectation about stress might account for the discrepancy between perceived and physiological stress. In a crossover experiment, we assessed cardioceptive accuracy in two ways (mental heartbeat tracking task and perception of heart rate), and induced physiological (handgrip exercise) and mental (N-back task) stress in 64 university students (51 % male, mean age 22.2). We assessed cardiac and electrodermal activity, and expected and perceived stress. We found that indicators of cardioceptive accuracy were not associated with cardiovascular reactivity. However, heart rate perception moderated the association between the change in heart rate and perceived stress in the physical but not in the mental task. Whereas heartbeat tracking accuracy was not associated with perceived stress. Moreover, perceived stress was predicted by the expected stress but not by the change in heart rate and electrodermal activity in the mental stress task. In conclusion, heart rate perception and expectation of stress may shape perceived stress more than actual physiological changes in moderate acute stress.

Brain regulates weight bearing bone through PGE2 skeletal interoception: implication of ankle osteoarthritis and pain.

Bone is a mechanosensitive tissue and undergoes constant remodeling to adapt to the mechanical loading environment. However, it is unclear whether the signals of bone cells in response to mechanical stress are processed and interpreted in the brain. In this study, we found that the hypothalamus of the brain regulates bone remodeling and structure by perceiving bone prostaglandin E2 (PGE2) concentration in response to mechanical loading. Bone PGE2 levels are in proportion to their weight bearing. When weight bearing changes in the tail-suspension mice, the PGE2 concentrations in bones change in line with their weight bearing changes. Deletion of cyclooxygenase-2 (COX2) in the osteoblast lineage cells or knockout of receptor 4 (EP4) in sensory nerve blunts bone formation in response to mechanical loading. Moreover, knockout of TrkA in sensory nerve also significantly reduces mechanical load-induced bone formation. Moreover, mechanical loading induces cAMP-response element binding protein (CREB) phosphorylation in the hypothalamic arcuate nucleus (ARC) to inhibit sympathetic tyrosine hydroxylase (TH) expression in the paraventricular nucleus (PVN) for osteogenesis. Finally, we show that elevated PGE2 is associated with ankle osteoarthritis (AOA) and pain. Together, our data demonstrate that in response to mechanical loading, skeletal interoception occurs in the form of hypothalamic processing of PGE2-driven peripheral signaling to maintain physiologic bone homeostasis, while chronically elevated PGE2 can be sensed as pain during AOA and implication of potential treatment.

From early relational experiences to non-suicidal self-injury in anorexia and bulimia nervosa: a structural equation model unraveling the role of impairments in interoception.

PURPOSE: Individuals with anorexia nervosa (AN) and bulimia nervosa (BN) frequently exhibit Non-Suicidal Self-Injury (NSSI), yet their co-occurrence is still unclear. To address this issue, the aim of this study was to elucidate the role of impairments in interoception in explaining the NSSI phenomenon in AN and BN, providing an explanatory model that considers distal (insecure attachment/IA and traumatic childhood experiences/TCEs) and proximal (dissociation and emotional dysregulation) risk factors for NSSI. METHOD: 130 patients with AN and BN were enrolled and administered self-report questionnaires to assess the intensity of NSSI behaviors, interoceptive deficits, IA, TCEs, emotional dysregulation and dissociative symptoms. RESULTS: Results from structural equation modeling revealed that impairments in interoception acted as crucial mediators between early negative relational experiences and factors that contribute to NSSI in AN and BN, particularly emotional dysregulation and dissociation. Precisely, both aspects of IA (anxiety and avoidance) and various forms of TCEs significantly exacerbated interoceptive deficits, which in turn are associated to the emergence of NSSI behaviors through the increase in levels of dissociation and emotional dysregulation. CONCLUSIONS: The proposed model provided a novel explanation of the occurrence of NSSIs in patients with AN and BN by accounting for the significance of interoception. LEVEL OF EVIDENCE: Level V-Cross-sectional observational study.

Delving into the relationship between regular physical exercise and cardiac interoception in two cross-sectional studies.

Cardiac interoception, the ability to sense and process cardiac afferent signals, has been shown to improve after a single session of acute physical exercise. However, it remains unclear whether repetitive engagement in physical exercise over time leads to long-term changes in cardiac interoceptive accuracy. It is also unknown whether those changes affect the neural activity associated with the processing of afferent cardiac signals, assessed by the heart-evoked potential (HEP). In this study, we aimed to investigate this hypothesis through two cross-sectional studies, categorizing participants as active or inactive based on physical fitness (Study I; N = 45) or self-reported physical activity levels (Study II; N = 60). Interoception was assessed at rest using the HEP (Studies I and II), the Heartbeat Counting task (Study II), and the Rubber Hand Illusion (RHI) (Study II). Study I showed strong evidence of better cardiovascular fitness in the active group than in the inactive group as well as robust between-group differences in electrocardiogram (ECG) recordings. Study 2 replicated the clear differences in ECG as a function of regular physical activity. Those results were expected due to clear differences in physical activity habits. In contrast, our analysis revealed no robust differences between groups across cardiac interoception tasks and the RHI, although the direct relevance of these measures to interoception remains under investigation. In sum, our results do not provide convincing evidence to support a strong version of the notion that regular physical exercise is associated with an enhanced in cardiac interoception.

Insula-cortico-subcortical networks predict interoceptive awareness and stress resilience.

BACKGROUND: Interoception, the neural sensing of visceral signals, and interoceptive awareness (IA), the conscious perception of interoception, are crucial for life survival functions and mental health. Resilience, the capacity to overcome adversity, has been associated with reduced interoceptive disturbances. Here, we sought evidence for our Insula Modular Active Control (IMAC) model that suggest that the insula, a brain region specialized in the processing of interoceptive information, realizes IA and contributes to resilience and mental health via cortico-subcortical connections. METHODS: 64 healthy participants (32 females; ages 18-34 years) answered questionnaires that assess IA and resilience. Mental health was evaluated with the Beck Depression Inventory II that assesses depressive mood. Participants also underwent a 15 minute resting-state functional resonance imaging session. Pearson correlations and mediation analyses were used to investigate the relationship between IA and resilience and their contributions to depressive mood. We then performed insula seed-based functional connectivity analyzes to identify insula networks involved in IA, resilience and depressive mood. RESULTS: We first demonstrated that resilience mediates the relationship between IA and depressive mood. Second, shared and distinct intra-insula, insula-cortical and insula-subcortical networks were associated with IA, resilience and also predicted the degree of experienced depressive mood. Third, while resilience was associated with stronger insula-precuneus, insula-cerebellum and insula-prefrontal networks, IA was linked with stronger intra-insula, insula-striatum and insula-motor networks. CONCLUSIONS: Our findings help understand the roles of insula-cortico-subcortical networks in IA and resilience. These results also highlight the potential use of insula networks as biomarkers for depression prediction.

Recognition of others' interoceptive states in those with and without eating disorders.

BACKGROUND: The ability to recognize one's own emotions is associated with one's ability to recognize others' emotions. Beyond the domain of emotion, however, the relationship between recognition of one's own internal states (interoception) and others' interoceptive states has not been investigated, either in the typical population or clinical groups with interoceptive difficulties (e.g. eating disorders; EDs). METHOD: This study investigated recognition of one's own and others' internal states in adults with and without eating disorders, using a high frequency visual noise paradigm. Participants completed self-report measures of interoception, alexithymia (difficulties recognising one's own emotional internal states) and ED symptomatology, and the Heartbeat Counting Task measure of cardiac interoceptive accuracy. RESULTS: Alexithymia was significantly negatively correlated with recognition of others' interoceptive states. EDs were not associated with difficulties recognising others' interoceptive states. CONCLUSIONS: The ability to recognise one's own emotional internal states is associated with the recognition of others' interoceptive states, which may contribute to social skills and the ability to care for others.

Visceral sensitivity, hunger responsiveness, and satiety responsiveness: Associations between facets of gastrointestinal interoception and disordered eating profiles in an undergraduate sample.

This preregistered study examined associations between empirically derived profiles of disordered eating in a diverse nonclinical sample and three facets of gastrointestinal (GI) interoception (visceral sensitivity, hunger responsiveness, satiety responsiveness). University students (n = 591; 53.3% women; 23.0% Hispanic) completed the Visceral Sensitivity Index, Adult Eating Behavior Questionnaire, and Eating Pathology Symptom Inventory. Latent profile analysis was conducted in Mplus v8.3 with four behavioral indicators (restricting, binge eating, excessive exercise, purging [binary]). Facets of GI interoception predicting odds of disordered eating profile membership compared to an asymptomatic group were evaluated. Five profiles were identified. Facets of GI interoception differentially predicted odds of membership in disordered eating profiles. However, higher scores on all three facets of GI interoception were associated with increased odds of membership in a high disordered eating profile. The relationship between distinct facets of GI interoception and specific disordered eating patterns appears nuanced, though individuals displaying a range of disordered eating behaviors may exhibit broad GI interoceptive dysfunction. Findings are consistent with the recent emphasis on idiographic treatment approaches for disordered eating and may have implications for screening among university students. Prospective longitudinal work and extension to clinical samples is needed.

Heightened interoception in adults with fibromyalgia.

Previous research suggests that the processing of internal body sensations (interoception) affects how we experience pain. Some evidence suggests that people with fibromyalgia syndrome (FMS) - a condition characterised by chronic pain and fatigue - may have altered interoceptive processing. However, extant findings are inconclusive, and some tasks previously used to measure interoception are of questionable validity. Here, we used an alternative measure - the Phase Adjustment Task (PAT) - to examine cardiac interoceptive accuracy in adults with FMS. We examined: (i) the tolerability of the PAT in an FMS sample (N = 154); (ii) if there are differences in facets of interoception (PAT performance, PAT-related confidence, and scores on the Private Body Consciousness Scale) between an FMS sample and an age- and gender-matched pain-free sample (N = 94); and (iii) if subgroups of participants with FMS are identifiable according to interoceptive accuracy levels. We found the PAT was tolerable in the FMS sample, with additional task breaks and a recommended hand posture. The FMS sample were more likely to be classified as 'interoceptive' on the PAT, and had significantly higher self-reported interoception compared to the pain-free sample. Within the FMS sample, we identified a subgroup who demonstrated very strong evidence of being interoceptive, and concurrently had lower fibromyalgia symptom impact (although the effect size was small). Conversely, self-reported interoception was positively correlated with FMS symptom severity and impact. Overall, interoception may be an important factor to consider in understanding and managing FMS symptoms. We recommend future longitudinal work to better understand associations between fluctuating FMS symptoms and interoception.

Acute fasting modulates autonomic nervous system function and ambulatory cardiac interoception.

Intermittent fasting has been associated with diverse physical and psychological health benefits. According to previous research, fasting-induced alterations in psychophysiological functioning should facilitate the accurate detection of an internal bodily signal (like the heart), which is referred to as interoceptive accuracy. In two within-subjects studies we aimed to examine whether an intermittent fasting protocol (i) evokes distinct autonomic nervous system changes in the laboratory and (ii) improves (objectifiable) interoceptive accuracy and sensibility (i.e., the subjective belief in perceiving bodily signals) in everyday life. Study 1 (N = 36) found increasing heart rate variability (precisely, the root mean square of successive differences; RMSSD) accompanied by a more vascular than myocardial response following a 16 h fast. Study 2 (N = 40) applied an ecological momentary assessment design including intermittent fasting (8 h normal eating followed by 16 h fasting) and normal eating (24 h normal eating) for three consecutive days each. Findings suggested a tendency toward higher interoceptive accuracy and sensibility during the fasting regimen, which was particularly pronounced in individuals exhibiting lower RMSSD. Together, findings suggest that (short-term) fasting seems to facilitate momentary attention to organismic cues due to alterations in autonomic nervous system function.

Bonding with bump: Interoceptive sensibility moderates the relationship between pregnancy body satisfaction and antenatal attachment.

PROBLEM: There is limited understanding and contradictory results regarding the contribution of the pregnant bodily experience to antenatal attachment. BACKGROUND: Antenatal attachment is an important aspect of pregnancy, which has been linked with positive maternal and infant outcomes. Given the profound physical process of pregnancy, it is likely that bodily experience is implicated in antenatal attachment, with research supporting the involvement of pregnancy body (dis)satisfaction. However, previous research reveals conflicting results and has only focused on exteroceptive bodily experience (appearance) rather than internal physiological sensations (interoception). AIM: To examine the relative contributions of both external and internal bodily experience in antenatal attachment. METHODS: This cross-sectional study collected online survey data from 159 pregnant participants with measures capturing interoceptive sensibility (subjective experience of interoception), pregnancy body dissatisfaction and antenatal attachment. FINDINGS: We replicated previous findings that pregnancy body dissatisfaction is related to antenatal attachment. However, the relationship between pregnancy body dissatisfaction and antenatal attachment was moderated by worry about interoceptive signals. The interoceptive construct of body trust was most strongly associated with antenatal attachment. DISCUSSION: The results suggest that interoception is important for antenatal attachment, particularly feelings of body trust. Moreover, for individuals who were less worried about bodily sensations, high levels of body dissatisfaction were associated with low attachment scores, whilst for those who were more concerned about these sensations, the relationship between body dissatisfaction and antenatal attachment was mitigated. CONCLUSION: The results suggest that focusing on internal sensations may be a protective strategy against pregnancy body dissatisfaction to strengthen maternal bonds.

Interoception as a function of hypnotizability during rest and a heartbeat counting task.

The hypnotizability-related differences in morpho-functional characteristics of the insula could at least partially account for the differences in interoceptive accuracy (IA) observed between high and low hypnotizable individuals (highs, lows). Our aim was to investigate interoceptive processing in highs, lows, and medium hypnotizable individuals (mediums), who represent most of the population, during a 10-minute open eyes relaxation condition (Part 1) and three repetitions of consecutive 2-minute open eyes, closed eyes, and heartbeat counting conditions, followed by a 2-minute post-counting condition (Part 2). Electrocardiogram and electroencephalogram were recorded in 14 highs, 14 mediums, and 18 lows, classified according to the Stanford Hypnotic Susceptibility Scale: Form A. Heartbeat-evoked cortical potentials (HEP) were extracted throughout the entire session, and IA index was obtained for the heartbeat counting task (HCT). In Part 1, significant hypnotizability-related differences were observed in the right central region in both early and late HEP components, with lows showing positive amplitudes and highs/mediums showing negative amplitudes. In Part 2, the same group differences were limited to the early component. Moreover, in the left frontal regions, only mediums modified their HEP during the counting task with respect to the open/closed eyes conditions, whereas highs displayed HEP differences between counting and post-counting rest. HCT did not show significant group differences. In conclusion, highs and mediums seem to be more similar than mediums and lows regarding HEP, despite the absence of significant differences in HCT. Nonetheless, a negative correlation between hypnotizability scores and HEP amplitudes was observed in the regions showing group differences.