Differential effects of anxiety and depression on interoceptive accuracy

Three roots of online toxicity: disembodiment, accountability, and disinhibition

Online communication is central to modern social life, yet it is often linked to toxic manifestations and reduced well-being. How and why online communication enables these toxic social effects remains unanswered. In this opinion, we propose three roots of online toxicity: disembodiment, limited accountability, and disinhibition. We suggest that virtual disembodiment results in a chain of psychological states primed for deleterious social interaction. Drawing from differences between face-to-face and online interactions, the framework highlights and addresses the fundamental problems that result in impaired communication between individuals and explicates its effects on social toxicity online.

Disembodiment and Affective Resonances in Esketamine Treatment of Depersonalized Depression Subtype: Two Case Studies

INTRODUCTION

Dissociative experiences are considered undesirable ketamine's adverse events. However, they might be crucial for ketamine's antidepressant effects, at least in some depression subtypes. Current understandings of ketamine's therapeutic potentials converge on the so-called "relaxed prior hypothesis," suggesting that glutamatergic blockage up-weights bottom-up surprising somatosensory/affective states. As a result, ketamine improves short-term plasticity in depression by enhancing sensitivity to interoceptive signals.

METHODS

We selected 2 case studies for their paradigmatic description of "depersonalized depression" (Entfremdungsdepression) symptoms. Patients were included in a 6-month-long esketamine program for treatment resistant depression, during which we collected their spontaneous experience with esketamine. According to a neurophenomenological approach, we combined subjective reports from unstructured clinical interviews and the review of previous objective neuroimaging results and neurocomputational models to unveil the relation between esketamine antidepressant effects and interoceptive sensitivity.

RESULTS

According to our clinical observations, esketamine-induced dissociation might be particularly effective in the depersonalized depression subtype, in which interoceptive awareness and interaffectivity are particularly compromised. Ketamine and esketamine's dissociative effects and particularly disembodiment might suspend previously acquired patterns of feeling, sensing, and behaving.

CONCLUSIONS

Coherently with previous research, we suggest that esketamine-induced disembodiment allows for a transient window of psychological plasticity and enhanced sensitivity, where the body recovers its permeability to affective affordances.

When virtual reality becomes psychoneuroendocrine reality: A stress(or) review

This review article was awarded the Dirk Hellhammer award from ISPNE in 2023. It explores the dynamic relationship between stressors and stress from a historical view as well as a vision towards the future of stress research via virtual reality (VR). We introduce the concept of a "syncytium," a permeable boundary that blurs the distinction between stress and stressor, in order to understand why the field of stress biology continues to inadequately measure stress alone as a proxy for the force of external stressors. Using Virtual Reality (VR) as an illustrative example to explicate the black box of stressors, we examine the distinction between 'immersion' and 'presence' as analogous terms for stressor and stress, respectively. We argue that the conventional psychological approaches to stress measurement and appraisal theory unfortunately fall short in quantifying the force of the stressor, leading to reverse causality fallacies. Further, the concept of affordances is introduced as an ecological or holistic tool to measure and design a stressor's force, bridging the gap between the external environment and an individual's physiological response to stress. Affordances also serve to ameliorate shortcomings in stress appraisal by integrating ecological interdependencies. By combining VR and psychobiological measures, this paper aims to unravel the complexity of the stressor-stress syncytium, highlighting the necessity of assessing both the internal and external facets to gain a holistic understanding of stress physiology and shift away from reverse causality reasoning. We find that the utility of VR extends beyond presence to include affordance-based measures of immersion, which can effectively model stressor force. Future research should prioritize the development of tools that can measure both immersion and presence, thereby providing a more comprehensive understanding of how external stressors interact with individual psychological states.

Sensory processing across eating disorders: A systematic review and meta-analysis of self-report inventories

OBJECTIVE

This review investigated the extant literature regarding the relationship between eating disorder diagnoses and sensory processing as measured by validated and reliable self-report inventories. Increasing evidence highlights the role of sensory processing in cognitive functions. Sensory processing is implicated in mental-ill health, including eating disorders (ED) and body image disturbances. However, the pathophysiological underpinnings of sensory processing, encompassing exteroception and interoception, in relation to ED remain underexplored.

METHOD

We included studies involving participants aged 15 years or older with an eating disorder diagnosis confirmed by semi-structured or structured interviews. We further limited inclusion to articles using validated and reliable self-report instruments to measure sensory processing. Our meta-analysis focused on studies using the interoceptive awareness subscale from the second version of the Eating Disorder Inventory. We used the Critical Appraisal checklist for quasi-experimental studies to assess the quality of included articles.

RESULTS

There were 19 studies that met our inclusion criteria. Most studies showed moderate-to-high quality. Anorexia nervosa (AN) and bulimia nervosa (BN) were associated with heightened exteroception. Moreover, people with AN reported a heightened sense of taste compared to those with BN. Our meta-analysis comprising 10 studies, 19 samples, and 6382 participants revealed that AN (binge-purge subtype) and BN were associated with increased interoceptive difficulties compared to AN (restrictive subtype) or binge-eating disorder.

DISCUSSION

Overall, this review emphasizes the need for a deeper investigation into sensory processing, spanning both exteroception and interoception, in relation to ED. This may prove important for individualizing person-centered care.

PUBLIC SIGNIFICANCE

How people process internal, for example, hunger, and external, for example, taste and sensations is known to influence cognition and mental-ill health, including ED and body image disturbances. However, the ways in which sensory processing may contribute to ED are incompletely understood. We found that individuals with AN or BN experienced heightened exteroception, while people with an eating disorder characterized by purging reported increased interoceptive difficulties. These patterns could inform the development of more personalized treatments.

Intranasal Oxytocin Improves Interoceptive Accuracy and Heartbeat-Evoked Potentials During a Cardiac Interoceptive Task

BACKGROUND

Interoception represents perception of the internal bodily state, which is closely associated with social/emotional processing and physical health in humans. Understanding the mechanism that underlies interoceptive processing, particularly its modulation, is therefore of great importance. Given the overlap between oxytocinergic pathways and interoceptive signaling substrates in both peripheral visceral organs and the brain, intranasal oxytocin administration is a promising approach for modulating interoceptive processing.

METHODS

Using a double-blind, placebo-controlled, between-participant design, we recruited 72 healthy male participants who performed a cardiac interoceptive task during electroencephalograph and electrocardiograph recording to examine whether intranasal administration of the neuropeptide oxytocin could modulate interoceptive processing. We also collected data in a resting state to examine whether we could replicate previous findings.

RESULTS

The results showed that in the interoceptive task, oxytocin increased interoceptive accuracy at the behavioral level, which was paralleled by larger heartbeat-evoked potential amplitudes in frontocentral and central regions on the neural level. However, there were no significant effects of oxytocin on electroencephalograph or electrocardiograph during resting state.

CONCLUSIONS

These findings suggest that oxytocin may only have a facilitatory effect on interoceptive processing under task-based conditions. Our findings not only provide new insights into the modulation of interoceptive processing via targeting the oxytocinergic system but also provide proof-of-concept evidence for the therapeutic potential of intranasal oxytocin in mental disorders with dysfunctional interoception.

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.

Transdiagnostic failure to adapt interoceptive precision estimates across affective, substance use, and eating disorders: A replication and extension of previous results

Recent Bayesian theories of interoception suggest that perception of bodily states rests upon a precision-weighted integration of afferent signals and prior beliefs. In a previous study, we fit a computational model of perception to behavior on a heartbeat tapping task to test whether aberrant precision-weighting could explain misestimation of cardiac states in psychopathology. We found that, during an interoceptive perturbation designed to amplify afferent signal precision (inspiratory breath-holding), healthy individuals increased the precision-weighting assigned to ascending cardiac signals (relative to resting conditions), while individuals with anxiety, depression, substance use disorders, and/or eating disorders did not. In this pre-registered study, we aimed to replicate and extend our prior findings in a new transdiagnostic patient sample (N = 285) similar to the one in the original study. As expected, patients in this new sample were also unable to adjust beliefs about the precision of cardiac signals - preventing the ability to accurately perceive changes in their cardiac state. Follow-up analyses combining samples from the previous and current study (N = 719) also afforded power to identify group differences between narrower diagnostic categories, and to examine predictive accuracy when logistic regression models were trained on one sample and tested on the other. With this confirmatory evidence in place, future studies should examine the utility of interceptive precision measures in predicting treatment outcomes and test whether these computational mechanisms might represent novel therapeutic targets.

Interoceptive training impacts the neural circuit of the anterior insula cortex

Interoception is the perception of afferent information that arises from anywhere and everywhere within the body. Recently, interoceptive accuracy could be enhanced by cognitive training. Given that the anterior insula cortex (AIC) is a key node of interoception, we hypothesized that resting functional connectivity (RSFC) from AIC was involved in an effect of interoceptive training. To address this issue, we conducted a longitudinal intervention study using interoceptive training and obtained RSFC using fMRI before and after the intervention. A heartbeat perception task evaluated interoceptive accuracy. Twenty-two healthy volunteers (15 females, age 19.9 ± 2.0 years) participated. After the intervention, interoceptive accuracy was enhanced, and anxiety levels and somatic symptoms were reduced. Also, RSFC from AIC to the dorsolateral prefrontal cortex (DLPFC), superior marginal gyrus (SMG), anterior cingulate cortex (ACC), and brain stem, including nucleus tractus solitarius (NTS) were enhanced, and those from AIC to the visual cortex (VC) were decreased according to enhanced interoceptive accuracy. The neural circuit of AIC, ACC, and NTS is involved in the bottom-up process of interoception. The neural circuit of AIC, DLPFC, and SMG is involved in the top-down process of interoception, which was thought to represent the cognitive control of emotion. The findings provided a better understanding of neural underpinnings of the effect of interoceptive training on somatic symptoms and anxiety levels by enhancing both bottom-up and top-down processes of interoception, which has a potential contribution to the structure of psychotherapies based on the neural mechanism of psychosomatics.

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.

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.

Brain-heart interaction disruption in major depressive disorder: disturbed rhythm modulation of the cardiac cycle on brain transient theta bursts

Brain neurons support arousal and cognitive activity in the form of spectral transient bursts and cooperate with the peripheral nervous system to adapt to the surrounding environment. However, the temporal dynamics of brain-heart interactions have not been confirmed, and the mechanism of brain-heart interactions in major depressive disorder (MDD) remains unclear. This study aimed to provide direct evidence for brain-heart synchronization in temporal dynamics and clarify the mechanism of brain-heart interaction disruption in MDD. Eight-minute resting-state (closed eyes) electroencephalograph and electrocardiogram signals were acquired simultaneously. The Jaccard index (JI) was used to measure the temporal synchronization between cortical theta transient bursts and cardiac cycle activity (diastole and systole) in 90 MDD patients and 44 healthy controls (HCs) at rest. The deviation JI was used to reflect the equilibrium of brain activity between diastole and systole. The results showed that the diastole JI was higher than the systole JI in both the HC and MDD groups; compared to HCs, the deviation JI attenuated at F4, F6, FC2, and FC4 in the MDD patients. The eccentric deviation JI was negatively correlated with the despair factor scores of the HAMD, and after 4 weeks of antidepressant treatment, the eccentric deviation JI was positively correlated with the despair factor scores of the HAMD. It was concluded that brain-heart synchronization existed in the theta band in healthy individuals and that disturbed rhythm modulation of the cardiac cycle on brain transient theta bursts at right frontoparietal sites led to brain-heart interaction disruption in MDD.

Cluster analysis of heart failure patients based on their psychological and physical symptoms and predictive analysis of cluster membership

AIM

Patients with heart failure experience multiple co-occurring symptoms that lower their quality of life and increase hospitalization and mortality rates. So far, no heart failure symptom cluster study recruited patients from community settings or focused on symptoms predicting most clinical outcomes. Considering physical and psychological symptoms together allows understanding how they burden patients in different combinations. Moreover, studies predicting symptom cluster membership using variables other than symptoms are lacking. We aimed to (a) cluster heart failure patients based on physical and psychological symptoms and (b) predict symptom cluster membership using sociodemographic/clinical variables.

DESIGN

Secondary analysis of MOTIVATE-HF trial, which recruited 510 heart failure patients from a hospital, an outpatient and a community setting in Italy.

METHODS

Cluster analysis was performed based on the two scores of the Hospital Anxiety-Depression scale and two scores of the Heart-Failure Somatic Perception Scale predicting most clinical outcomes. ANOVA and chi-square test were used to compare patients' characteristics among clusters. For the predictive analysis, we split the data into a training set and a test set and trained three classification models on the former to predict patients' symptom cluster membership based on 11 clinical/sociodemographic variables. Permutation analysis investigated which variables best predicted cluster membership.

RESULTS

Four clusters were identified based on the intensity and combination of psychological and physical symptoms: mixed distress (high psychological, low physical symptoms), high distress, low distress and moderate distress. Clinical and sociodemographic differences were found among clusters. NYHA-class (New York Heart Association) and sleep quality were the most important variables in predicting symptom cluster membership.

CONCLUSIONS

These results can support the development of tailored symptom management intervention and the investigation of symptom clusters' effect on patient outcomes. The promising results of the predictive analysis suggest that such benefits may be obtained even when direct access to symptoms-related data is absent.

IMPLICATIONS

These results may be particularly useful to clinicians, patients and researchers because they highlight the importance of addressing clusters of symptoms, instead of individual symptoms, to facilitate symptom detection and management. Knowing which variables best predict symptom cluster membership can allow to obtain such benefits even when direct access to symptoms-data is absent.

IMPACT

Four clusters of heart failure patients characterized by different intensity and combination of psychological and physical symptoms were identified. NYHA class and sleep quality appeared important variables in predicting symptom cluster membership.

REPORTING METHOD

The authors have adhered to the EQUATOR guidelines STROBE to report observational cross-sectional studies.

PATIENT OR PUBLIC CONTRIBUTION

Patients were included only for collecting their data.

Vague sensations. About the background and consequences of discordance between actual and perceived physiological changes

Empirical evidence consistently shows that discordance, also called dissociation or discrepancy, between actual physiological (mainly visceral) events and their perceived counterparts is substantial. On the one hand, we typically do not perceive actual visceral events occurring in our bodies; on the other hand, sometimes we do perceive bodily changes that do not really take place. This narrative review presents the available empirical findings on the discordance, and summarizes possible explanations that approach the phenomenon from the viewpoint of evolution, cognitive development, and predictive processing. Also, the role of top-down factors, such as expectations and experiences is discussed. Finally, practically relevant consequences of the discordance are presented using the examples of mind-body practices, the placebo and nocebo phenomenon, and medically unexplained symptoms. It is concluded that the discordance between actual and perceived body changes can have a negative impact on health, mainly through issues with adherence and other behavioral factors. The existence of actual-perceived discordance should be taught and demonstrated in the elementary and high school, as well as in many areas of higher education.

From synaptic dysfunction to atypical emotional processing in autism

Autism spectrum disorder (ASD) is a complex neurodevelopmental condition mainly characterized by social impairments and repetitive behaviors. Among these core symptoms, a notable aspect of ASD is the presence of emotional complexities, including high rates of anxiety disorders. The inherent heterogeneity of ASD poses a unique challenge in understanding its etiological origins, yet the utilization of diverse animal models replicating ASD traits has enabled researchers to dissect the intricate relationship between autism and atypical emotional processing. In this review, we delve into the general findings about the neural circuits underpinning one of the most extensively researched and evolutionarily conserved emotional states: fear and anxiety. Additionally, we explore how distinct ASD animal models exhibit various anxiety phenotypes, making them a crucial tool for dissecting ASD's multifaceted nature. Overall, to a proper display of fear response, it is crucial to properly process and integrate sensorial and visceral cues to the fear-induced stimuli. ASD individuals exhibit altered sensory processing, possibly contributing to the emergence of atypical phobias, a prevailing anxiety disorder manifested in this population. Moreover, these individuals display distinctive alterations in a pivotal fear and anxiety processing hub, the amygdala. By examining the neurobiological mechanisms underlying fear and anxiety regulation, we can gain insights into the factors contributing to the distinctive emotional profile observed in individuals with ASD. Such insights hold the potential to pave the way for more targeted interventions and therapies that address the emotional challenges faced by individuals within the autism spectrum.

Pain experience in eating disorders: The mediating role of depression, alexithymia and interoceptive awareness

OBJECTIVE

Evidence suggests reduced sensitivity to pain due to high pain threshold in anorexia and bulimia nervosa and a possible role of depression, alexithymia and interoceptive awareness on pain experience. This study examined whether self-report and real-time evoked pain experience were mediated by depression, alexithymia and interoceptive awareness in a comprehensive sample of patients with eating disorders (ED).

METHOD

145 participants (90 ED, 55 healthy controls (HC)) underwent a real-time evoked examination of pain and completed self-report questionnaires for pain (Pain Detect Questionnaire (PD-Q), PD-Q VAS, Leeds Assessment of Neuropathic Symptoms and Signs), depression (BDI-II), interoceptive awareness Multidimensional Assessment of Interoceptive Awareness (MAIA), and alexithymia (TAS-20). Three mediation models, with ED diagnosis as independent variable, and BDI, MAIA and TAS-20 as mediators, were tested.

RESULTS

Participants with ED and HC exhibited similar pain type and intensity (self-report and real-time). Eating disorders diagnosis was associated with lower self-report pain intensity and non-neuropathic like pain experience (model 1-2). Depressive symptoms partially (model 1-2) or fully (model 3) mediated the association between ED diagnosis and pain experience, alone (model 1) or via alexithymia (model 3). Interoceptive awareness did not influence pain symptomatology.

DISCUSSION

ED diagnosis is associated with non-neuropathic and lower pain experience. However, concurrent depression and alexithymia are associated with higher pain symptoms and neuropathic features. These results could inform clinicians about the influence of psychopathology on pain experience in ED.

Transdiagnostic failure to adapt interoceptive precision estimates across affective, substance use, and eating disorders: A replication study

Recent computational theories of interoception suggest that perception of bodily states rests upon an expected reliability- or precision-weighted integration of afferent signals and prior beliefs. The computational psychiatry framework further suggests that aberrant precision-weighting may lead to misestimation of bodily states, potentially hindering effective visceral regulation and promoting psychopathology. In a previous study, we fit a Bayesian computational model of perception to behavior on a heartbeat tapping task to test whether aberrant precision-weighting was associated with misestimation of bodily states. We found that, during an interoceptive perturbation designed to amplify afferent signal precision (inspiratory breath-holding), healthy individuals increased the precision-weighting assigned to ascending cardiac signals (relative to resting conditions), while individuals with symptoms of anxiety, depression, substance use disorders, and/or eating disorders did not. A second study also replicated the pattern observed in healthy participants. In this pre-registered study, we aimed to replicate our prior findings in a new transdiagnostic patient sample (N=285) similar to the one in the original study. These new results successfully replicated those found in our previous study, indicating that, transdiagnostically, patients were unable to adjust beliefs about the reliability of interoceptive signals - preventing the ability to accurately perceive changes in their bodily state. Follow-up analyses combining samples from the previous and current study (N=719) also afforded the power to identify group differences within narrower diagnostic groups and to examine predictive accuracy when logistic regression models were trained on one sample and tested on the other. Given the increased confidence in the generalizability of these effects, future studies should examine the utility of interceptive precision measures in predicting treatment outcomes or identify whether these computational mechanisms might represent novel therapeutic targets for improving visceral regulation.

Depression and anxiety before and at the beginning of the COVID-19 pandemic and incident persistent symptoms: a prospective population-based cohort study

Many patients affected by COVID-19 suffer from debilitating persistent symptoms whose risk factors remained poorly understood. This prospective study examined the association of depression and anxiety symptoms measured before and at the beginning of the COVID-19 pandemic with the incidence of persistent symptoms. Among 25,114 participants [mean (SD) age, 48.72 years (12.82); 51.1% women] from the SAPRIS and SAPRIS-Sérologie surveys nested in the French CONSTANCES population-based cohort, depression and anxiety symptoms were measured with the Center for Epidemiologic Studies-Depression scale and the 12-item General Health Questionnaire before the pandemic, and with the 9-item Patient Health Questionnaire and the 7-Item Generalized Anxiety Disorder scale at the beginning of the pandemic (i.e., between April 6, 2020 and May 4, 2020). Incident persistent symptoms were self-reported between December 2020 and January 2021. The following variables were also considered: gender, age, educational level, household income, smoking status, BMI, hypertension, diabetes, self-rated health, and SARS-CoV-2 infection according to serology/PCR test results. After a follow-up of seven to ten months, 2329 participants (9.3%) had been infected with SARS-CoV-2 and 4262 (17.0%) reported at least one incident persistent symptom that emerged from March 2020, regardless of SARS-CoV-2 infection. In multi-adjusted logistic regression models, participants in the highest (versus the lowest) quartile of depressive or anxiety symptom levels before or at the beginning of the pandemic were more likely to have at least one incident persistent symptom (versus none) at follow-up [OR (95%CI) ranging from 2.10 (1.89-2.32) to 3.01 (2.68-3.37)], with dose-response relationships (p for linear trend <0.001). Overall, these associations were significantly stronger in non-infected versus infected participants, except for depressive symptoms at the beginning of the pandemic. Depressive symptoms at the beginning of the pandemic were the strongest predictor of incident persistent symptoms in both infected and non-infected participants [OR (95%CI): 2.88 (2.01-4.14) and 3.03 (2.69-3.42), respectively]. In exploratory analyses, similar associations were found for each symptom taken separately in different models. Depression and anxiety symptoms should be tested as a potential target for preventive interventions against persistent symptoms after an infection with SARS-CoV-2.

Dynamic heartbeat tracking beyond the laboratory: Introducing the novel Graz Ambulatory Interoception Task (GRAIT)

We present a novel ambulatory method, the Graz Ambulatory Interoception Task (GRAIT), to assess the accuracy of interoceptive beliefs (AccIB). This method captures both between- and within-person variations of AccIB by having participants counting perceived heartbeats in daily life. Reliability analyses showed high between-person (RkR = 0.99) and moderate within-person reliability (RCn = 0.62). Validity was supported by associations with an established laboratory task (r = 0.87). Within-person associations revealed that interoceptive sensibility, heart rate variability, and states of low arousal coupled with positive affect were linked to AccIB. Study 2 replicated these findings and showed a relationship between AccIB and self-control in everyday life, highlighting the importance of cardiac interoception and its relevance for health.

Aberrant single-subject morphological brain networks in first-episode, treatment-naive adolescents with major depressive disorder

Background

Neuroimaging-based connectome studies have indicated that major depressive disorder (MDD) is associated with disrupted topological organization of large-scale brain networks. However, the disruptions and their clinical and cognitive relevance are not well established for morphological brain networks in adolescent MDD.

Objective

To investigate the topological alterations of single-subject morphological brain networks in adolescent MDD.

Methods

Twenty-five first-episode, treatment-naive adolescents with MDD and 19 healthy controls (HCs) underwent T1-weighted magnetic resonance imaging and a battery of neuropsychological tests. Single-subject morphological brain networks were constructed separately based on cortical thickness, fractal dimension, gyrification index, and sulcus depth, and topologically characterized by graph-based approaches. Between-group differences were inferred by permutation testing. For significant alterations, partial correlations were used to examine their associations with clinical and neuropsychological variables in the patients. Finally, a support vector machine was used to classify the patients from controls.

Results

Compared with the HCs, the patients exhibited topological alterations only in cortical thickness-based networks characterized by higher nodal centralities in parietal (left primary sensory cortex) but lower nodal centralities in temporal (left parabelt complex, right perirhinal ectorhinal cortex, right area PHT and right ventral visual complex) regions. Moreover, decreased nodal centralities of some temporal regions were correlated with cognitive dysfunction and clinical characteristics of the patients. These results were largely reproducible for binary and weighted network analyses. Finally, topological properties of the cortical thickness-based networks were able to distinguish the MDD adolescents from HCs with 87.6% accuracy.

Conclusion

Adolescent MDD is associated with disrupted topological organization of morphological brain networks, and the disruptions provide potential biomarkers for diagnosing and monitoring the disease.

A multi-site German validation of the Interoceptive Accuracy Scale and its relation to psychopathological symptom burden

Altered interoception is thought to be implicated in the development of psychopathology. Recent proposals highlight the need to differentiate between dimensions of interoception to better understand its relation to mental health. Here, we validated a German version of the Interoceptive Accuracy Scale (IAS) and investigated the relationship between IAS scores and clinical outcomes, across seven samples from four research centers (N = 3462). The German IAS version was best explained by a one-factor structure that showed acceptable psychometric properties. We replicated previous findings showing a negative association between IAS scores and measures of alexithymia. IAS scores were negatively related to measures of clinical symptomatology (e.g., anxiety, depressive, and somatoform symptoms) and neurotic traits. These findings suggest that the German IAS is a reliable and valid instrument for subjective interoceptive accuracy. Results emphasize the importance of distinguishing between dimensions of interoception to understand its potential modulatory and protective role in psychopathology.

Topography and relationship-specific social touching in individuals displaying body image disturbances

Interpersonal touch is intimately related to the emotional bond between the touch giver and the touch receiver. Which bodily regions we touch in those individuals in our social network is relationship specific. Perception of interpersonal touch is altered in psychiatric disorders characterised by body image disturbances (BIDs). Here, we examined whether the 'imagined' experience of social touch in individuals with BIDs is body topography- and relationship-specific. By using an interactive media mobile App, the Virtual Touch Toolkit, high versus low levels of BIDs participants completed heatmaps of full-body virtual avatars, to indicate the body regions they find soothing/unpleasant to be touched by a loved one versus an acquaintance. Self-reports of interoceptive awareness and dysmorphic concerns were also measured. Overall, imagined touch was rated as the most soothing when received from a loved one, and also when this was delivered to 'social' body regions. The importance of the social relationship for the imagined tactile interactions was particularly evident for the high levels of BIDs group, with greater problems with interoceptive awareness predicting higher soothing touch ratings when this was received by a loved one. Despite the evidence that imagined bodily contacts between meaningful people is the most pleasant for socially acceptable bodily regions, our findings may suggest a greater sensitivity to relation-specific bodily patterns of social touch particularly in the high level of BIDs group. Heightened interoceptive awareness may also play a key role in this experience of bodily affective contacts. Future research for body-oriented therapy for BIDs is encouraged to systematically probe the efficacy of imagined social touch interaction protocols which use more plausible, ecological, scenarios where touch is delivered by loved ones and to socially acceptable bodily regions.

Insula neuroanatomical networks predict interoceptive awareness

Interoceptive awareness (IA), the subjective and conscious perception of visceral and physiological signals from the body, has been associated with functions of cortical and subcortical neural systems involved in emotion control, mood and anxiety disorders. We recently hypothesized that IA and its contributions to mental health are realized by a brain interoception network (BIN) linking brain regions that receive ascending interoceptive information from the brainstem, such as the amygdala, insula and anterior cingulate cortex (ACC). However, little evidence exists to support this hypothesis. In order to test this hypothesis, we used a publicly available dataset that contained both anatomical neuroimaging data and an objective measure of IA assessed with a heartbeat detection task. Whole-brain Voxel-Based Morphometry (VBM) was used to investigate the association of IA with gray matter volume (GMV) and the structural covariance network (SCN) of the amygdala, insula and ACC. The relationship between IA and mental health was investigated with questionnaires that assessed depressive symptoms and anxiety. We found a positive correlation between IA and state anxiety, but not with depressive symptoms. In the VBM analysis, only the GMV of the left anterior insula showed a positive association with IA. A similar association was observed between the parcellated GMV of the left dorsal agranular insula, located in the anterior insula, and IA. The SCN linking the right dorsal agranular insula with the left dorsal agranular insula and left hyper-granular insula were positively correlated with IA. No association between GMV or SCN and depressive symptoms or anxiety were observed. These findings revealed a previously unknown association between IA, insula volume and intra-insula SCNs. These results may support development of non-invasive neuroimaging interventions, e.g., neurofeedback, seeking to improve IA and to prevent development of mental health problems, such anxiety disorders.

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.

Do we need to accurately perceive our heartbeats? Cardioceptive accuracy and sensibility are independent from indicators of negative affectivity, body awareness, body image dissatisfaction, and alexithymia

Assessment of the acuity of heartbeat perception, dubbed cardioceptive accuracy, as well as its association with various psychological characteristics are hot topics of interoception research. In this study, we aimed (1) to replicate previously reported findings on the association between the mental tracking task and a novel motor tracking task that eliminates disturbing tactile sensations; and (2) to explore associations between performance in the latter task and indicators of negative affectivity (anxiety, depression, anxiety sensitivity, somatic symptom distress), alexithymia, body focus, and dissatisfaction with body image. 102 young people (age = 20.8±5.08 yrs) participated in the study. Mental tracking score was significantly higher than motor tracking scores, although they were strongly associated. Frequentist correlation analysis showed no significant associations between indicators of cardioceptive accuracy and questionnaire scores; Bayesian analysis indicated the lack of association for the majority of the cases. Similarly, detectors and non-detectors showed no differences in any of the assessed characteristics and Bayesian results typically supported the lack of associations. In conclusion, cardioceptive accuracy, as assessed with different tracking methods, is not associated with the aforementioned self-reported characteristics in young individuals.

Association of Hypnotizability, Interoception, and Emotion

The present scoping review reports the reciprocal relations between hypnotizability, interoception, and emotion. Brain morpho-functional differences may account for the lower interoceptive accuracy, higher interoceptive sensitivity, and different emotional strategies observed in highly hypnotizable participants with respect to medium-to-low hypnotizables. Since interoception is relevant to both physical and mental health and hypnotizability can predict both interoceptive abilities and the efficacy of interoception-based mental training, this allows for the development of new forms of treatment and rehabilitation.

Interoceptive abilities facilitate taking another's spatial perspective

Information can be perceived from a multiplicity of spatial perspectives, which is central to effectively understanding and interacting with our environment and other people. Interoception, the sense of the physiological state of our body, is also a fundamental component contributing to our perception. However, whether the perception of our inner body signals influences our ability to adopt and flexibly change between different spatial perspectives remains poorly understood. To investigate this, 90 participants completed tasks assessing multiple dimensions of interoception (interoceptive sensibility, cardiac interoceptive accuracy and awareness) and the Graphesthesia task to assess tactile spatial perspective-taking and its flexibility. The results revealed that higher cardiac interoceptive awareness is associated with greater consistency in adopting a perspective decentred from the self. Second, higher cardiac interoceptive accuracy was associated with slower and less accurate performance in switching from a decentred to an egocentred perspective. These results show that interoceptive abilities facilitate decentred spatial perspective-taking, likely reflecting stronger perceived boundaries between internal states and the external world.

[Role of psychological factors in post-COVID-19 condition]

Even after a mild episode of coronavirus disease 2019 (COVID-19), many patients suffer from persistent symptoms that can impair their quality of life for months. The potential role of psychological mechanisms in this post-COVID-19 condition, often referred to as long COVID, has been discussed early in the pandemic. Evidence supporting this hypothesis is now accumulating. First, a history of anxiety or depression is now an established risk factor for post-COVID-19 condition with a dose-response relationship and effect size similar to those of other known risk factors. This association extends to other forms of psychological distress, including perceived stress and loneliness. Second, specific beliefs about COVID-19 have been associated with the risk of subsequent similar symptoms, occurring weeks to several months later. Other studies, which have yet to be replicated, suggest an influence of the context of the initial infection (first versus second wave of the pandemic, before the emergence of significant variants and vaccination) and the trust in various sources of information about COVID-19 on the risk of subsequent symptoms. Bayesian models of perception can account for these results particularly well within a theoretical framework similar to that advanced for functional somatic disorders, integrating increased symptom expectations with decreased perception of the body internal state (interoception) and intolerance of uncertainty in the context of symptoms initially triggered by an infectious episode. These psychological mechanisms should obviously not be considered as exclusive. However, since they are modifiable, they could be targeted in clinical trials, within an integrative and multidisciplinary approach.

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.

Effects of emotional contexts on respiratory attention task performance

Negative emotions have been found associated with high prevalence of respiratory disease and increased subjective feelings of dyspnea, while positive emotional stimulus has been suggested to alleviate dyspneic feelings. However, the extent to which different emotional contexts affect individuals' respiratory interoceptive attention was not clear. Therefore, the purpose of this study was to investigate the influences of emotional contexts on respiratory interoceptive accuracy, and the relationships between respiratory interoceptive accuracy and negative emotions as well as respiratory symptoms. Fifty-six healthy participants completed the self-reported questionnaires of depression, anxiety, and respiratory symptoms. During the experiment, the participants were instructed to watch one neutral and one positive affective picture series and mentally count the number of perceived occlusions (reported at the end of the trials). The Wilcoxon Signed-Rank test and Spearman's correlations were used to examine the effect of the emotional pictures and to explore the relationships between the level of emotional status or respiratory symptoms and respiratory interoceptive task performance. The significance level was set at p < 0.05. Our results did not show a significant difference in participants' occlusion counting task performance between the neutral and positive emotional context. However, Spearman's Rho correlation analysis revealed that depression level was negatively correlated with accuracy of the task performance in the neutral emotional context, and this relationship diminished in the positive emotional context. In summary, our study demonstrated that negative emotional status, especially depression, may lead to decreased respiratory interoceptive accuracy. Future studies are recommended to test the effect of positive emotional context on respiratory interoceptive task performance in individuals with clinical depression and anxiety.

The unique face of comorbid anxiety and depression: increased interoceptive fearfulness and reactivity

Anxiety and depression commonly co-occur, yet the underlying brain and behavioral processes are poorly understood. Here we examined the hypothesis that individuals with comorbid anxiety and depression would show increased fearful reactivity to an aversive interoceptive perturbation relative to depressed-only individuals. One-hundred and eighty anxious and/or depressed participants from the Tulsa 1000 study completed multi-level behavioral or functional magnetic resonance imaging assessments of interoception and nociception including breath-hold and cold-pressor challenges, and heartbeat perception and interoceptive attention tasks. One-hundred and four individuals with comorbid depression and anxiety disorders (Dep+Anx) were propensity matched with 52 individuals with depression-only (Dep). Data were analyzed using mixed-effects linear regression. The Dep+Anx group showed significantly greater self-reported fear of suffocation during breath holding (Wilcoxon r = 0.23) and reduced cold pain tolerance (R ² = 0.027) signified by hand removal during immersion. However, these groups did not differ with respect to neutrally-valenced behavioral indices of heartbeat perception or neural indices of interoceptive attention. Individuals with comorbid depression and anxiety, vs. those with only depression, show increased respiratory fearfulness and nociceptive reactivity during perturbations of these signals, whilst showing similar interoceptive awareness in the absence of perturbation. Our findings suggest that individuals with comorbid anxiety and depression process aversive interoceptive and nociceptive signals differently than those with depression alone, providing support for a process model of increased threat sensitivity and hyperarousal in anxious depression.

Interoceptive differences in elite sprint and long-distance runners: A multidimensional investigation

Interoception, the process of detecting and interpreting bodily sensations, may facilitate self-regulation and thereby play a crucial role in achieving elite performance in competitive sports. However, there is a lack of research conducted in world-class athletes. In the present research, two studies examined self-reported (interoceptive sensibility) and behavioural (interoceptive accuracy) interoception in elite (top 100 ranking) sprint and long-distance runners, and non-athletes. Study 1 used the Multidimensional Assessment of Interoceptive Awareness Questionnaire. Sprinters reported having better regulation of attention to internal sensations, greater emotional awareness, better self-regulation, and reported a greater propensity to listen to their body for insight, than distance runners. Compared to non-athletes, sprinters and distance runners had more bodily trust, attention regulation, and self-regualtion. Additionally, elite athletes reported lower emotional awareness, self-regulation, and body listening. Study 2 examined cardioception using two tasks: The Heartbeat Counting Task, and The Heartbeat Detection Task. Elite and non-elite runners performed the tasks under two conditions; in silence, and whilst listening to pre-recorded crowd noise that simulated the live sounds of spectators during a sporting event. Sprinters and distance runners were able to maintain heartbeat detection accuracy when distracted, whereas non-athletes could not. Across both tasks, compared to non-athletes, sprinters and distance runners were more confident than non-athletes in their interoceptive percept. Additionally, elite athletes compared to non-elite athletes were less accurate when counting their heartbeat and were characterised by a higher interoceptive prediction error. Athletic populations have altered interoceptive abilities.

Increased insula response to interoceptive attention following mindfulness training is associated with increased body trusting among patients with depression

Interoceptive dysfunction is often present in anxiety and depression. We investigated the effects of an 8-week intervention, Mindfulness Training for Primary Care (MTPC), on brain mechanisms of interoceptive attention among patients with anxiety and/or depression. We hypothesized that fMRI brain response to interoception in the insula, a region known for interoceptive processing, would increase following the MTPC intervention, and that such increases would be associated with post-intervention changes in self-reported measures of interoceptive awareness. Adults (n = 28) with anxiety and/or depression completed baseline and post-intervention fMRI visits, including a task in which they alternated between focusing on their heartbeat (interoception (INT)) and a control visual attention task (exteroception (EXT)). Following MTPC, we observed increased evoked fMRI response (relative to baseline) in left anterior insula during the INT-EXT task contrast (z > 3.1, p < 0.001 corrected). In patients with moderate-to-severe depression as defined by the Patient Reported Outcomes Measurement Information System (PROMIS), increased post-intervention insula response was associated with increased Body Trusting, a subscale of the Multidimensional Assessment of Interoceptive Awareness (z > 3.1, p = 0.007 corrected). This study demonstrates that patients with mood disorders may respond differentially to mindfulness-based treatment depending on depression severity, and that among those who are more depressed, increased trusting in one's own body sensations and experiencing the body as a safe place to attend to may be necessary components of positive responses to mindfulness-based interventions.

The Differential Relationship Between Self-Reported Interoceptive Accuracy and Attention With Psychopathology

Abstract. Background: Only recently has interoception been discussed as a common risk factor for psychopathology. Recent approaches distinguish between the ability to accurately perceive ( interoceptive accuracy) and the propensity to attend ( interoceptive attention) to internal signals. Objective: To examine the latent structure of self-reported interoceptive accuracy and attention and their relationships to psychopathology. Methods: We used a confirmatory factor analysis to clarify the latent structure of interoceptive accuracy and attention. Structural equation modeling was utilized to determine relationships between both abilities with internalizing and somatoform symptomatology according to the HiTOP model ( Kotov et al., 2017 ). Data from N = 619 persons from the German general population were analyzed. Results: Interoceptive attention showed significant positive relationships with all psychopathological traits ( r = .221 to r = .377), whereas interoceptive accuracy was negatively associated with internalizing symptomatology ( r = -.106). Conclusion: The present findings indicate that personal beliefs about interoceptive abilities have different influences on psychopathological developments.

Relationship between interoceptive sensibility, age, and COVID-19 anxiety during the first national lockdown in the United Kingdom

Objectives: Interoception refers to the multidimensional representation of the internal states of the body, including sensation, appraisal, integration, and regulation. COVID-19 targets internal respiratory, temperature and gastrointestinal systems, thus posing a threat to humans that causes anxiety. Here, we examined the relationship between interoceptive sensibility and COVID-19 anxiety during the first UK national lockdown, when uncertainties surrounding the virus were at their peak.Methods: Between April and July 2020, N = 232 individuals across four age-categories completed questionnaires measuring interoceptive sensibility (BPQ-SF and MAIA-2), an adapted State-Trait-Anxiety Inventory (STAI) to assess COVID-19 anxiety, and a Perceived Quality of Life (QoL) questionnaire.Results: Higher scores on the BPQ-SF were related to higher levels of COVID-19 anxiety, while the MAIA-2 subscales Not Worrying, Attention Regulation, and Trusting of bodily signals were related to lower levels of COVID-19 anxiety. Age was related to lower levels of COVID-19 anxiety yet showed no significant (Bonferroni-corrected) relationship with interoceptive dimensions. Trait anxiety, Not Worrying, perceived quality of work, and COVID-19-related media consumption emerged as significant predictors of COVID-19 anxiety.Conclusion: Findings suggest that interoceptive dimensions differentially relate to COVID-19 anxiety irrespective of age, with implications for managing health anxiety and adaptive behaviour during a pandemic across the lifespan.

Going beyond the DSM in predicting, diagnosing, and treating autism spectrum disorder with covarying alexithymia and OCD: A structural equation model and process-based predictive coding account

Background

There is much overlap among the symptomology of autistic spectrum disorders (ASDs), obsessive compulsive disorders (OCDs), and alexithymia, which all typically involve impaired social interactions, repetitive impulsive behaviors, problems with communication, and mental health.

Aim

This study aimed to identify direct and indirect associations among alexithymia, OCD, cardiac interoception, psychological inflexibility, and self-as-context, with the DV ASD and depression, while controlling for vagal related aging.

Methodology

The data involved electrocardiogram (ECG) heart rate variability (HRV) and questionnaire data. In total, 1,089 participant's data of ECG recordings of healthy resting state HRV were recorded and grouped into age categories. In addition to this, another 224 participants completed an online survey that included the following questionnaires: Yale-Brown Obsessive Compulsive Scale (Y-BOCS); Toronto Alexithymia Scale 20 (TAS-20); Acceptance and Action Questionnaire (AAQII); Depression, Anxiety, and Stress Scale 21 (DAS21); Multi-dimensional Assessment of Interoceptive Awareness Scale (MAIA); and the Self-as-Context Scale (SAC).

Results

Heart rate variability was shown to decrease with age when controlling for BMI and gender. In the two SEMs produced, it was found that OCD and alexithymia were causally associated with autism and depression indirectly through psychological inflexibility, SAC, and ISen interoception.

Conclusion

The results are discussed in relation to the limitations of the DSM with its categorical focus of protocols for syndromes and provide support for more flexible ideographic approaches in diagnosing and treating mental health and autism within the Extended Evolutionary Meta-Model (EEMM). Graph theory approaches are discussed in their capacity to depict the processes of change potentially even at the level of the relational frame.

Alteration of interoceptive sensitivity: expanding the spectrum of behavioural disorders in amyotrophic lateral sclerosis

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder with progressive loss of upper and lower motor neurons. Non-motor-symptoms, such as cognitive, emotional, autonomic, and somatosensory alterations, have been also described. Interoception represents the link between the body and brain, since it refers to the ability to consciously perceive the physical condition of the inner body, including one's heartbeat (i.e., interoceptive sensitivity, IS).

OBJECTIVES

To evaluate IS in ALS patients by means of a well-established task: the heartbeat perception task. Moreover, we evaluated possible correlations between IS and neuropsychological, affective, and disease-related characteristics.

METHODS

Fifty-five ALS patients (mean-age = 60.3 ± 12.5 years; mean disease-duration = 20.9 ± 18.8 months) and 41 caregivers (CG) underwent the heartbeat perception task and an extensive evaluation of motor, cognitive, body awareness, affective, and emotion domains.

RESULTS

ALS patients showed lower IS than CG (0.68 ± 0.24 vs 0.82 ± 0.16; p = 0.003). Significant correlations were found between IS and self-reported measures of alexithymia (subscale of Toronto Alexithymia scale-20 "difficulties in describing feelings"; rho =  - .391, p = .003) and interoceptive awareness (subscale of Multidimensional assessment of interoceptive awareness "not worrying about pain"; rho = .405, p = .002). No significant differences were found on questionnaires for depression and anxiety between patients with ALS and their caregivers (p > .05).

CONCLUSIONS

ALS patients show reduced interoceptive sensitivity that is associated with poorer ability to describe feelings and with lower focalization on pain, regardless of cognitive and motor impairment. Alteration of interoception may represent a specific behavioural sign within the spectrum of emotion processing deficits described in ALS patients.

Disentangling the role of interoceptive sensibility in alexithymia, emotion dysregulation, and depression in healthy individuals

Interoception, a multifaceted concept defined as the perception of internal bodily signals, is crucially involved in mental health in general and in emotion regulation in particular, being interoceptive sensibility (IS) one of the most studied interoceptive processes. The main objective of this study was to explore the relationships between IS and emotion regulation processes, analyzing the role of the eight IS dimensions assessed by the Multidimensional Assessment of Interoceptive Awareness-2 (MAIA-2) in alexithymia, emotion dysregulation, and depression. Additionally, this study also aimed to validate the MAIA-2 in a Spanish sample. To do so, 391 healthy adults, native Peninsular Spanish speakers (61.0% women, Mage = 29.00, SDage = 11.40), completed the MAIA-2 and other self-reported questionnaires to measure alexithymia, emotion dysregulation, and depressive symptoms. Results showed that lower scores on the IS dimensions that involve an accepting attitude toward the bodily signals (e.g., not-worrying) were related to alexithymia and emotion dysregulation, which, in turn, predicted depression. Moreover, the eight-factor structure of the MAIA-2 was confirmed with acceptable fit indices. This study highlights the multidimensional nature of the IS and the relevance of IS dimensions that involve a positive appraisal of the body in regulating emotions.

The Effects of a 3-Week Heartbeat Perception Training on Interoceptive Abilities

Recent studies showed promising short-term effects of heartbeat perception training on interoceptive abilities. Research on the effects of heartbeat perception training on interoceptive abilities over time is sparse. Therefore, the aim of this study was to examine the short-term effects and the effects of a 3-week heartbeat perception training over time on interoceptive abilities, namely, cardiac interoceptive accuracy (IAc) and interoceptive sensibility (IS). A total of 40 healthy participants were randomized to the intervention group (n = 20) or the control group (n = 20). The intervention group conducted three cardiac biofeedback sessions (one per week) at the laboratory, whereas the control group watched a documentary instead. Interoceptive abilities were assessed via the heartbeat perception task (IAc) and confidence ratings (IS) at baseline, after each laboratory session, and 1 week after the last session (post-measurement). IAc was significantly increased in the intervention group compared to the control group after the first training session (short-term effect). There were no significant improvements in IS due to the first session, and neither on IAc nor IS over time. Descriptive trends of improved interoceptive abilities over time were found in both groups. Single session of heartbeat perception training seems to be a promising approach to improve IAc. Future research should further investigate the long-term effects of diverse heartbeat perception training varying in frequency and intensity of the training sessions in diverse samples aiming to improve interoceptive abilities.

Relationship of Interoceptive Accuracy With Risky Decision-Making and Treatment Outcomes in Male Patients With Alcohol Use Disorder

Abstract. Lower levels of interoceptive awareness (IA) may be present in individuals with substance use disorder (SUD), and damage to related brain regions caused by substance use may disrupt IA. Disturbance in the bodily feedback system may fail to engage in effective decision-making. This study focused on the premise that interoceptive accuracy (IAc), as the primary construct of IA, is implicated in SUD and that poor IAc is linked to risky decision-making and adversely affects treatment outcomes. Eighty-five patients with alcohol use disorder (AUD) (current severity: moderate or severe) and 87 healthy control subjects were enrolled in the present study. All participants performed the heart rate tracking task and a computerized version of the Iowa gambling task (IGT). Characteristics of patients’ addiction profiles were assessed with the Addiction Profile Index (API) Clinical Form. IAc and IGT scores of patients with AUD were lower than healthy controls. IGT scores of patients with low IAc were lower than those of patients with high IAc and decreased IAc is predictive of decreased IGT scores. No significant differences were determined in treatment outcomes at 3, 6, and 12 months after hospitalization between the low-IAc and high-IAc patient groups. Our results suggest that IAc is implicated in AUD and that poor IAc is predictive of increased risky decision-making. Risky decision-making that results in substance use may be partly related to a deficit in the interoceptive ability to guide behavior. Focus on IAc without reference to complex clinical case presentations in AUD makes it difficult to draw any definitive conclusions about the role of IAc in clinical outcomes.

Embodiment-related risk factors for Posttraumatic Stress, Anxiety and Depression in female victims of intimate partner violence

A central notion in the field of embodiment is that body sensorimotor processes and body mental representations influence emotion, cognition and behavior. By affecting the body, intimate partner violence (IPV) can leave victims with a fragile self, and significant physical and mental health problems. In this study, we aim to examine embodiment-related variables and mental health of female victims of IPV, as well as the impact of embodiment on mental health. A total of 38 female victims of IPV (mean age 40.3 ± 10.9 years) were recruited from shelters and the community. The study assessed the levels of Posttraumatic Stress Disorder (PTSD), Anxiety and Depression, and abilities of Movement Imagery, Interoceptive Accuracy, Interoceptive Sensibility, Body Ownership and Bodily Dissociation. Univariate, bivariate and binary regression analysis were used. PTSD, Anxiety and Depression were highly prevalent among our sample, alongside with altered values of body ownership and interoception. All three mental health disorders were significantly correlated with interoceptive self-regulation, interoceptive trusting, and bodily dissociation. For this group of women, each unit rise in the bodily dissociation scale increased two and six times the risk for developing Depression and Anxiety, respectively. The embodiment of female victims of IPV is altered, and higher bodily dissociation can be a risk factor for the development of mental health problems. Restoration of embodiment-related functions could be important for the victims to overcome the negative effects of violent relationships.

A heartbeat away from a valid tracking task. An empirical comparison of the mental and the motor tracking task

Individuals' ability to perceive their heartbeats, called cardioceptive accuracy, is assessed with various paradigms. Performance in the mental and a novel motor tracking task that eliminates disturbing tactile sensations was assessed at rest and during walking with the participation of 45 young people. Significantly higher scores in the mental tracking task than in the motor tracking task were found. Scores obtained at rest were consistently higher than their walking counterparts. Motor responses showed no temporal association with heartbeats for 84% of participants at rest and 95% during walking. Overall, participants' cardioceptive accuracy at rest and under slight physical activity was poor. Even if people rely on their heartbeat-related sensations during their daily activity, it is either not the ability that is assessed by the tracking tasks, or it is a relatively poor source of information about the actual state of the body.

From the inside out: Interoceptive feedback facilitates the integration of visceral signals for efficient sensory processing

Neuroscientific studies have mainly focused on the way humans perceive and interact with the external world. Recent work in the interoceptive domain indicates that the brain predictively models information from inside the body such as the heartbeat and that the efficiency with which this is executed can have implications for exteroceptive processing. However, to date direct evidence underpinning these hypotheses is lacking. Here, we show how the brain predictively refines neural resources to process afferent cardiac feedback and uses these interoceptive cues to enable more efficient processing of external sensory information. Participants completed a repetition-suppression paradigm consisting of a neutral repeating face. During the first face presentation, they heard auditory feedback of their heartbeat which either coincided with the systole of the cardiac cycle, the time at which cardiac events are registered by the brain or the diastole during which the brain receives no internal cardiac feedback. We used electroencephalography to measure the heartbeat evoked potential (HEP) as well as auditory (AEP) and visual evoked potentials (VEP). Exteroceptive cardiac feedback which coincided with the systole produced significantly higher HEP amplitudes relative to feedback timed to the diastole. Elevation of the HEP in this condition was followed by significant suppression of the VEP in response to the repeated neutral face and a stepwise decrease of AEP amplitude to repeated heartbeat feedback. Our results hereby show that exteroceptive heartbeat feedback coinciding with interoceptive signals at systole enhanced interoceptive cardiac processing. Furthermore, the same cue facilitating interoceptive integration enabled efficient suppression of a visual stimulus, as well as repetition suppression of the AEP across successive auditory heartbeat feedback. Our findings provide evidence that the alignment of external to internal signals can enhance the efficiency of interoceptive processing and that cues facilitating this process in either domain have beneficial effects for internal as well as external sensory processing.

Cortical Sources of Respiratory Mechanosensation, Laterality, and Emotion: An MEG Study

Airway obstruction activates mechanoreceptors that project to the cerebral cortices in humans, as evidenced by scalp encephalography recordings of cortical neuronal activation, i.e., respiratory-related evoked potential (RREP). However, neural evidence of both high spatial and temporal resolution of occlusion-elicited cortical activation in healthy individuals is lacking. In the present study, we tested our hypothesis that inspiratory mechanical stimuli elicit neural activation in cortical structures that can be recorded using magnetoencephalography (MEG). We further examined the relationship between depression and respiratory symptoms and hemispheric dominance in terms of emotional states. A total of 14 healthy nonsmoking participants completed a respiratory symptom questionnaire and a depression symptom questionnaire, followed by MEG and RREP recordings of inspiratory occlusion. Transient inspiratory occlusion of 300 ms was provided randomly every 2 to 4 breaths, and approximately 80 occlusions were collected in every study participant. Participants were required to press a button for detection when they sensed occlusion. Respiratory-related evoked fields (RREFs) and RREP peaks were identified in terms of latencies and amplitudes in the right and left hemispheres. The Wilcoxon signed-rank test was further used to examine differences in peak amplitudes between the right and left hemispheres. Our results showed that inspiratory occlusion elicited RREF M1 peaks between 80 and 100 ms after triggering. Corresponding neuromagnetic responses peaked in the sensorimotor cortex, insular cortex, lateral frontal cortex, and middle frontal cortex. Overall, the RREF M1 peak amplitude in the right insula was significantly higher than that in the left insula (p = 0.038). The RREP data also showed a trend of higher N1 peak amplitudes in the right hemisphere compared to the left (p = 0.064, one-tailed). Subgroup analysis revealed that the laterality index of sensorimotor cortex activation was significantly different between higher- and lower-depressed individuals (−0.33 vs. −0.02, respectively; p = 0.028). For subjective ratings, a significant relationship was found between an individual’s depression level and their respiratory symptoms (Spearman’s rho = 0.54, p = 0.028, one-tailed). In summary, our results demonstrated that the inspiratory occlusion paradigm is feasible to elicit an RREF M1 peak with MEG. Our imaging results showed that cortical neurons were activated in the sensorimotor, frontal, middle temporal, and insular cortices for the M1 peak. Respiratory occlusion elicited higher cortical neuronal activation in the right insula compared to the left, with a higher tendency for right laterality in the sensorimotor cortex for higher-depressed rather than lower-depressed individuals. Higher levels of depression were associated with higher levels of respiratory symptoms. Future research with a larger sample size is recommended to investigate the role of emotion and laterality in cerebral neural processing of respiratory sensation.

A single oral dose of citalopram increases interoceptive insight in healthy volunteers

RATIONALE

Interoception is the signalling, perception, and interpretation of internal physiological states. Many mental disorders associated with changes of interoception, including depressive and anxiety disorders, are treated with selective serotonin reuptake inhibitors (SSRIs). However, the causative link between SSRIs and interoception is not yet clear.

OBJECTIVES

To ascertain the causal effect of acute changes of serotonin levels on cardiac interoception.

METHODS

Using a within-participant placebo-controlled design, forty-seven healthy human volunteers (31 female, 16 male) were tested on and off a 20 mg oral dose of the commonly prescribed SSRI, citalopram. Participants made judgements on the synchrony between their heartbeat and auditory tones and then expressed confidence in each judgement. We measured three types of interoceptive cognition.

RESULTS

Citalopram increased cardiac interoceptive insight, measured as correspondence of self-reported confidence to the likelihood that interoceptive judgements were actually correct. This effect was driven by enhanced confidence for correct interoceptive judgements and was independent of measured cardiac and reported subjective effects of the drug.

CONCLUSIONS

An acute change of serotonin levels can increase insight into the reliability of inferences made from cardiac interoceptive sensations.

Interoception and alcohol: Mechanisms, networks, and implications

Interoception refers to the perception of the internal state of the body and is increasingly being recognized as an important factor in mental health disorders. Drugs of abuse produce powerful interoceptive states that are upstream of behaviors that drive and influence drug intake, and addiction pathology is impacted by interoceptive processes. The goal of the present review is to discuss interoceptive processes related to alcohol. We will cover physiological responses to alcohol, how interoceptive states can impact drinking, and the recruitment of brain networks as informed by clinical research. We also review the molecular and brain circuitry mechanisms of alcohol interoceptive effects as informed by preclinical studies. Finally, we will discuss emerging treatments with consideration of interoception processes. As our understanding of the role of interoception in drug and alcohol use grows, we suggest that the convergence of information provided by clinical and preclinical studies will be increasingly important. Given the complexity of interoceptive processing and the multitude of brain regions involved, an overarching network-based framework can provide context for how focused manipulations modulate interoceptive processing as a whole. In turn, preclinical studies can systematically determine the roles of individual nodes and their molecular underpinnings in a given network, potentially suggesting new therapeutic targets and directions. As interoceptive processing drives and influences motivation, emotion, and subsequent behavior, consideration of interoception is important for our understanding of processes that drive ongoing drinking and relapse.

Effects of a Single Yoga Session on Cardiac Interoceptive Accuracy and Emotional Experience

BACKGROUND

There is an increasing body of research supporting the idea that cardiac interoceptive accuracy (IAc) can be improved by training. Findings concerning the effects of a single yoga session on IAc and the related construct emotional experience are sparse. The aim of this study was to examine if a single yoga session increases IAc and improves emotional experience.

METHODS

137 students were randomly assigned to a 20-min yoga session (n = 47), an endurance session (n = 46), or an inactive control condition (n = 44). IAc and emotional experience were assessed before and after the sessions.

RESULTS

There were no significant changes in IAc, or positive and negative affect. IAc at baseline and the change in positive effect were found as predictors for IAc after the yoga session.

CONCLUSION

A 20-min yoga session seems to be not applicable to improve IAc and emotional experience. Future studies should investigate long-term interventions and diverse healthy and clinical populations.

Atypical interoception as a common risk factor for psychopathology: A review

The inadequacy of a categorial approach to mental health diagnosis is now well-recognised, with many authors, diagnostic manuals and funding bodies advocating a dimensional, trans-diagnostic approach to mental health research. Variance in interoception, the ability to perceive one's internal bodily state, is reported across diagnostic boundaries, and is associated with atypical functioning across symptom categories. Drawing on behavioural and neuroscientific evidence, we outline current research on the contribution of interoception to numerous cognitive and affective abilities (in both typical and clinical populations), and describe the interoceptive atypicalities seen in a range of psychiatric conditions. We discuss the role that interoception may play in the development and maintenance of psychopathology, as well as the ways in which interoception may differ across clinical presentations. A number of important areas for further research on the role of interoception in psychopathology are highlighted.

The Effects of a Standardized Cognitive-Behavioural Therapy and an Additional Mindfulness-Based Training on Interoceptive Abilities in a Depressed Cohort

BACKGROUND

Interoceptive accuracy and sensibility are decreased in depressive samples. However, different studies showed that cognitive-behavioural therapy (CBT) and mindfulness interventions are promising approaches to improve interoceptive abilities. Based on these findings, the study aims to investigate the pre-post effect of CBT in a depressive sample. Additionally, we examined the effect of mindfulness-based stress reduction (MBSR) training in the context of CBT.

METHODS

Sixty depressive patients were investigated over four weeks, with two conditions-CBT vs. CBT + MBSR. Further, the changes in interoceptive abilities (interoceptive accuracy and sensibility) of the depressive patients were compared to baseline data of healthy controls.

RESULTS

The depressive patients showed significantly higher levels of depression and lower mindfulness and interoceptive abilities than healthy controls. The depressive sample showed a significant decrease in depressive symptoms and increased mindfulness and interoceptive abilities after CBT. Lastly, depressive patients of the CBT + MBSR condition did not differ from those who only received CBT in the levels of depression, mindfulness or interoceptive abilities over the time course.

DISCUSSION

This study demonstrates a positive effect of CBT on interoceptive abilities in a depressive sample. It is shown that the depressive sample did not profit from additional mindfulness training. It can be concluded that CBT is an efficient treatment, resulting in increased interoceptive abilities. Unexpectedly, the combination of CBT and MBSR has no additional effect on these changes. Future studies should investigate the effect of MBSR as a stand-alone therapy.

Altered effective connectivity in sensorimotor cortices is a signature of severity and clinical course in depression

Research into neurobiology of depression primarily focuses on its complex psychological aspects. Here we propose an alternative approach and target sensorimotor alterations—a prominent but often neglected feature of depression. We demonstrated using resting-state functional MRI data and computational modeling that top-down and bottom-up information flow in sensory and motor cortices is altered with increasing depression severity in a way that is consistent with depression symptoms. Depression-associated changes were found to be consistent across sessions, amenable to treatment and of effect size sufficiently large to predict whether somebody has mild or severe depression. These results pave the way for an avenue of research into the neural underpinnings of mental health conditions.

Functional neuroimaging research on depression has traditionally targeted neural networks associated with the psychological aspects of depression. In this study, instead, we focus on alterations of sensorimotor function in depression. We used resting-state functional MRI data and dynamic causal modeling (DCM) to assess the hypothesis that depression is associated with aberrant effective connectivity within and between key regions in the sensorimotor hierarchy. Using hierarchical modeling of between-subject effects in DCM with parametric empirical Bayes we first established the architecture of effective connectivity in sensorimotor cortices. We found that in (interoceptive and exteroceptive) sensory cortices across participants, the backward connections are predominantly inhibitory, whereas the forward connections are mainly excitatory in nature. In motor cortices these parities were reversed. With increasing depression severity, these patterns are depreciated in exteroceptive and motor cortices and augmented in the interoceptive cortex, an observation that speaks to depressive symptomatology. We established the robustness of these results in a leave-one-out cross-validation analysis and by reproducing the main results in a follow-up dataset. Interestingly, with (nonpharmacological) treatment, depression-associated changes in backward and forward effective connectivity partially reverted to group mean levels. Overall, altered effective connectivity in sensorimotor cortices emerges as a promising and quantifiable candidate marker of depression severity and treatment response.