Alexithymia is associated with a multidomain, multidimensional failure of interoception: Evidence from novel tests

A non-systematic overview review of self-focused emotion regulation in autistic individuals through the lens of the extended process model

Difficulties regulating emotions have been coined as inherent to autism, possibly even presenting a core difficulty of autism. While several models of emotion regulation have been proposed in the past, in this targeted review article, we aim to map emotion regulation difficulties in autistic individuals within the framework of the extended process model of emotion regulation. This model can be considered the most comprehensive one currently incorporating not only different emotion regulation strategy groups but also different stages and processes involved in successful self-focused emotion regulation. Within this model, we will identify areas and domains as specifically impacted by autistic individuals. We will also outline gaps in the literature and provide suggestions for future research that can help deepen our understanding of the emotion regulation processes of autistic individuals. The ultimate goal is to develop specific support programs that address specific emotion regulation mechanisms, providing a much more individualized support approach.Lay abstractWhat do we already know about emotion regulation in autism?We know that many autistic children, youth, and adults experience difficulties regulating emotions. Existing research has focused mainly on the differences in emotion regulation capabilities between autistic and non-autistic individuals, the relationships between autistic traits and emotion regulation, and how emotion regulation relates to other outcomes, such as social skills and mental health.What does this paper add?We want to take a new approach to review the existing emotion regulation research through the lens of a specific theoretical model: the extended process model of emotion regulation. Professor James Gross developed this model. It consists of four emotion regulation phases: identification, selection, implementation, and monitoring.Our review revealed specific areas within these emotion regulation phases that could significantly impact the emotion regulation experiences of autistic individuals. We also outline the gaps in the research and propose avenues for future investigation.Implications for practiceBy deepening our understanding of emotion regulation in autistic individuals through the proposed future research, researchers and clinicians can pave the way for the development of tailored support programs. These programs will directly target specific emotion regulation mechanisms, offering a much-needed individualized support approach.

Breaking through the mind-body divide: patient priorities for interoception research

Background

Interoception-sensation, interpretation, and prediction of bodily signals-is reliably disrupted across a wide range of mental health conditions. A growing body of evidence suggests that interoception is a putative mechanism, or 'active ingredient', of effective psychological and pharmacological treatments. Anecdotally, patients with psychiatric disorders report differences in bodily experiences. However, formal priority setting by people with lived experience of mental health conditions has so far been overlooked in this rapidly expanding research area.

Methods

This article takes a mixed-methods approach to investigate experiences of bodily signals in individuals with mental health conditions and determine patients' research priorities. We recruited two UK samples in the context of an in-person workshop (N = 25) and online (N = 47), between April and July 2024. All contributors had a diagnosis of at least one mental health condition. Using a combination of written contributions and small group discussions, we explored the most relevant bodily sensations for patients' mental health, how bodily sensations were experienced by patients, and which research priorities were considered most important.

Findings

Patients' contributions emphasised the multimodal nature of interoception, in particular the importance of less frequently studied modalities such as the stomach and muscle tension, as well as the need to consider the causes and consequences of distressing bodily sensations. We summarise ten key research priorities for patients, spanning three themes: causes, management, and clinical/research approach to interoception in mental health. These priorities include investigating the impact of bodily signals on social contexts, techniques to manage distressing signals, and a shift of approach towards integrating mental and physical health in clinical/research settings.

Interpretation

Together, this broad scoping study establishes new, transdiagnostic, patient-led priorities for the developing field of interoception in psychiatry to ensure future research focusses on the areas of greatest impact for people with mental health conditions.

Funding

This work was supported by a Wellcome Mental Health award to C.L.N. and S.G. (226778/Z/22/Z), intramural funding from the UK Medical Research Council (MC/UU/00030/12), and a Wellcome Career Development Award to C.L.N. (226490/Z/22/Z). G.M. is funded by an ESRC DTP Studentship (RG84395). This research was also supported by the NIHR Cambridge Biomedical Research Centre (BRC-1215-20014).

Interoceptive Mechanisms and Emotional Processing

Interoception, the sensing of internal bodily signals, is intricately linked with the experience of emotions. Various theoretical models of emotion incorporate aspects of interoception as a fundamental component alongside higher-order processes such as the appraisal of internal signals guided by external context. Interoception can be delineated into different dimensions, which include the nature of afferent signals, the accuracy with which they can be sensed, their neural processing, and the higher-order interpretation of these signals. This review methodically evaluates these interoceptive dimensions through empirical research to illustrate their role in shaping emotions. Clinical and neurodevelopmental conditions characterized by altered emotional profiles, such as anxiety, depression, schizophrenia, posttraumatic stress disorder, emotionally unstable personality disorder, and autism, exhibit distinct changes in interoception. Various therapeutic approaches, including behavioral, pharmacological, and psychological strategies, may be efficacious for treating conditions associated with emotional alterations by targeting interoceptive mechanisms.

Exploring the Link Between Interoception and Symptom Severity in Premature Ventricular Contractions

Background/Objectives: The physiological basis underlying symptomatic versus asymptomatic premature ventricular contractions (PVCs) remains poorly understood. However, symptomatic PVCs can significantly impair quality of life. In patients without structural heart disease, symptom intensity is crucial for guiding management strategies and determining the need for medical or surgical intervention. In this study, we aimed, for the first time, to examine the associations between PVC symptoms and cardiac interoception. Methods: This study included 34 participants with PVCs (20 women; median age = 42 years; 17 participants had asymptomatic PVCs) without concomitant disorders. Interoception was assessed through interoceptive accuracy (IA) probed by two behavioral tests-mental tracking (MT) and heartbeat detection (HBD)-and the neurophysiological marker of cardiac interoception, the heartbeat-evoked potentials (HEPs). Symptom intensity scores reported by patients served as the response variable in the regression analysis, with IA and HEP as predictors. Other factors such as sex, age, percent of body fat, trait anxiety, and alexithymia were added to the models as confounding variables. Results: IAMT was significantly higher in patients with symptomatic PVCs. IAMT and HEP modulation for the HBD task were associated with symptom intensity. A combined regression model incorporating both metrics showed the highest predictive accuracy for symptom severity. Adding confounding variables improved model quality (lower AIC); however, only the male sex emerged as a significant negative predictor for symptom intensity. Conclusions: Our findings confirm a significant association between interoception and PVC symptom severity. Integrating behavioral and neurophysiological interoception measures enhances symptom prediction accuracy, suggesting new ways to develop diagnostic and non-invasive treatment strategies targeting interoception in PVC management.

Relationship of interoceptive accuracy in acne vulgaris patients: A prospective, controlled study

Acne vulgaris (AV) is a chronic inflammatory skin condition predominantly observed during adolescence. Interoception accuracy (IAc) refers to the ability to perceive internal bodily states such as hunger and thirst. Since the brain and skin originate from the same embryological layer, the ectoderm, it is hypothesized that skin changes and disorders might affect individual perceptions. The purpose of this study is to evaluate the relationship between IAc and AV. This study included 94 AV patients and 94 sex- and age-matched healthy controls. The participants completed the Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), Dermatology Life Quality Index (DLQI), and heartbeat perception task to assess IAc. The severity of acne was assessed using the Global Acne Grading System (GAGS). Acne patients had lower IAc scores than controls did (P = 0.026). Severe depression or anxiety symptoms were associated with lower IAc scores (P = 0.027, P = 0.046). Acne severity did not significantly affect IAc scores. There was a weak negative connection between the DLQI score and IAc (r = -0.208, P = 0.022), suggesting that lower quality of life is correlated with reduced IAc. Gender significantly influenced IAc. As a result, individuals with acne may have a reduced capacity to accurately perceive internal bodily states, potentially impacting overall well-being. Enhancing interoception might positively contribute to AV treatment and management.

Neurodivergence, intersectionality, and eating disorders: a lived experience-led narrative review

Autistic people and those with attention deficit hyperactivity disorder are at a high risk of developing an eating disorder. While there is limited evidence on the relationship between other forms of neurodivergence and eating disorders, research suggests associations between giftedness, intellectual disability, obsessive-compulsive disorder, psychosis, Tourette's syndrome, and disordered eating. Factors underlying disordered eating and/or eating disorder risk for neurodivergent people are multifaceted and complex, encompassing a wide range of intertwined psychosocial, environmental, and biological processes. Moreover, research shows that neurodivergent individuals experience poorer treatment outcomes compared to neurotypical individuals. However, there is a paucity of research in this area overall. More specifically, lived experience-led research remains rare, despite its critical role for improving individualised eating disorder care, as well as mental healthcare more broadly. Indeed, the importance of eating disorder care individuation is increasingly being recognised, particularly within the context of neurodivergence, given the heterogeneous experiences and support needs of neurodivergent people affected by disordered eating and/or eating disorders. Furthermore, despite documented overlaps between various forms of neurodivergence (e.g., co-occurring autism and attention deficit hyperactivity disorder), research looking at eating disorders in the context of neurodivergence through a transdiagnostic perspective is scarce. This lived experience-led narrative review aims to shed light on the intersectional factors underlying elevated disordered eating and/or eating disorder risk for neurodivergent individuals. First, an overview of prevalence data is provided, followed by a thematic framework identifying factors underlying disordered eating and/or eating disorder risk in relation to neurodivergence. A critical appraisal of current eating disorder research and care is then offered before suggestions for neurodiversity-affirming eating disorder care are made. In this view, this paper offers a foundation for future empirical work in this nascent field of inquiry by providing a lived experience-led, transdiagnostic, and intersectional account of eating disorders in the context of neurodivergence.

Higher inflammatory proteins predict future depressive symptom severity among adolescents with lower emotional clarity

BACKGROUND

A growing body of work has implicated inflammation in the pathogenesis of depression. As not all individuals with heightened levels of peripheral inflammation develop symptoms of depression, additional work is needed to identify other factors that catalyze the relationship between inflammation and depressive symptoms. Given that elevated levels of inflammatory activity can induce a variety of emotional changes, the present study examined whether emotional clarity, the trait-like ability to identify, discern, and express one's emotions, influences the strength of the association between inflammatory signaling and concurrent and prospective symptoms of depression.

METHODS

Community adolescents (N = 225, Mage = 16.63 years), drawn from a larger longitudinal project investigating sex and racial differences in depression onset, provided blood samples to determine peripheral levels of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and C-reactive protein (CRP) at a baseline visit, along with self-report measures of emotional clarity and depressive symptom severity. Depressive symptom severity was assessed again at a follow-up visit approximately 5-months after baseline.

RESULTS

Hierarchical multiple regressions detected a significant interaction between inflammatory markers and emotional clarity on future depression severity, controlling for baseline depressive symptoms. Specifically, among adolescents with low levels of emotional clarity, higher levels of IL-6, CRP, and inflammatory composite scores were significantly associated with greater future depression severity.

CONCLUSIONS

These results indicate that low emotional clarity and high inflammatory signaling may jointly confer risk for prospective depressive symptom severity among adolescents. Therapeutic interventions that improve emotional clarity may reduce risk of depressive symptoms among adolescents with low-grade peripheral inflammation.

Alexithymia and illness perceptions in persons with multiple sclerosis and their partners

Illness perceptions (IPs) encompass opinions regarding the nature, severity and curability of a disease. The aim of this cross-sectional study was to investigate the association between alexithymia and IPs among persons with multiple sclerosis (PwMS) and their partners, as well as within the dyads composed of PwMS and partners. PwMS referred to the Multiple Sclerosis Center of the University Hospital "Policlinico-San Marco" from 11th August 2021 to 7th January 2022 and their partners completed a battery of questionnaires, including the Toronto Alexithymia Scale-20 and the Illness Perception Questionnaire Revised. A dyadic data analysis (Actor-Partner Interdependence Model) was performed to test the effect of alexithymic traits both on a person's own illness perceptions (actor effect) and on the partner's illness perceptions (partner effect). 100 PwMS (71 women; mean age 47.6 ± 10.4 years) and 100 partners (29 women; mean age 49.1 ± 10.8 years), with a mean partnership duration of 20.1 ± 11.7 years, were enrolled. At the dyadic analysis, statistically significant small-to-moderate actor and partner effects were found considering alexithymia (total score and alexithymic facets) and IPs, whereby higher alexithymic traits related to higher negative perceptions (i.e. consequences, emotional representations) and lower positive ones (i.e. coherence, treatment control). Our findings support the relationship between alexithymia and negative illness appraisals. This data may inform therapeutic interventions aimed at reducing alexithymic traits, which in turn may reduce negative, and potentially dysfunctional, illness perceptions.

Interoceptive sensibility and alcohol craving in Polish prisoners: the role of alexithymia and emotional dysregulation

Introduction

Alcohol craving, characterized by a strong desire or compulsion to consume alcohol, is a prominent symptom of substance dependence syndrome. Research indicates that alcohol craving is a significant factor leading to the termination of abstinence. The mechanisms underlying the activation of alcohol craving remain not fully understood. The urge to reach for alcohol may be stimulated by emotions, memories, thoughts, or bodily sensations, as well as external factors. It has been postulated that individuals with high levels of interoceptive sensibility tend to exhibit a high degree of alexithymia and emotion dysregulation in the context of alcohol craving. Deficits in identifying and verbalizing emotions, along with an operational thinking style, facilitate alcohol consumption by impeding accurate insight into one's mental state, thereby hindering the comprehension of bodily states, emotions, and the regulation of self.

Method

This study involved 160 inmates incarcerated in a prison in Poland, awaiting participation in therapy for individuals with substance dependence following psychiatric diagnosis. Four questionnaires were used in the study: multidimensional Assessment of Interoceptive Sensibility (MAIA) for interoceptive sensibility, Toronto Alexithymia Scale (TAS-20) for alexithymia, Difficulties in Emotion Regulation Scale (DERS) for emotional dysregulation, and the Penn Alcohol Craving Scale (PACS) for alcohol craving assessment.

Results

The results of the study are as follows: the study findings indicated that alexithymia and emotional dysregulation significantly mediates the relationship between interoceptive sensibility and alcohol craving. The indirect effect for both factors was found to be significant, similar to the indirect effect observed for alexithymia as an mediator. However, in the case of emotional dysregulation, no significant indirect effect was observed.

Conclusion

Our study provides insights into the potential contribution of interoceptive sensibility to the heightened risk of alcohol dependence. Specifically, impaired interoceptive sensibility may be associated with the development of alexithymia and emotional dysregulation, potentially rendering individuals more susceptible to alcohol craving. Interoceptive sensibility could serve as a prerequisite for the cultivation of positive emotional processing skills.

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.

Interoceptive attention and mood in daily life: an experience-sampling study

Theories of emotion ascribe a fundamental role to the processing of bodily signals (interoception) in emotional experience. Despite evidence consistent with this, current knowledge is limited by a focus on interoceptive accuracy and laboratory-based interoception measures. This experience-sampling study examines how state interoceptive attention and state emotional experience are related in everyday life, providing the first data to our knowledge examining: (1) within-subject fluctuations in interoceptive attention across domains, and (2) the relationship between trait and state interoception. Compared with rates of exteroceptive attention (auditory attention: engaged 83% of the time), interoceptive signals captured attention approximately 20% of the time, with substantial within- and between-person variability across domains. There were relationships between interoceptive attention and emotion in daily life (greater attention being associated with more negative valence and fatigue) that were specific to interoceptive attention (different patterns were observed with exteroceptive attention). State measures of interoceptive (but not exteroceptive) attention were correlated with the trait interoceptive attention, but not accuracy. Results underscore the relationship between interoceptive attention and emotion, providing new insights into interoceptive attention and the structure of interoceptive ability. Future research should examine the source(s) of within- and between-person variability in interoceptive and exteroceptive attention and its relationship with emotional experience. This article is part of the theme issue 'Sensing and feeling: an integrative approach to sensory processing and emotional experience'.

Individual differences in interoception and autistic traits share altered facial emotion perception, but not recognition per se

While alterations in both physiological responses to others' emotions as well as interoceptive abilities have been identified in autism, their relevance in altered emotion recognition is largely unknown. We here examined the role of interoceptive ability, facial mimicry, and autistic traits in facial emotion processing in non-autistic individuals. In an online Experiment 1, participants (N = 99) performed a facial emotion recognition task, including ratings of perceived emotional intensity and confidence in emotion recognition, and reported on trait interoceptive accuracy, interoceptive sensibility and autistic traits. In a follow-up lab Experiment 2 involving 100 participants, we replicated the online experiment and additionally investigated the relationship between facial mimicry (measured through electromyography), cardiac interoceptive accuracy (evaluated using a heartbeat discrimination task), and autistic traits in relation to emotion processing. Across experiments, neither interoception measures nor facial mimicry accounted for a reduced recognition of specific expressions with higher autistic traits. Higher trait interoceptive accuracy was rather associated with more confidence in correct recognition of some expressions, as well as with higher ratings of their perceived emotional intensity. Exploratory analyses indicated that those higher intensity ratings might result from a stronger integration of instant facial muscle activations, which seem to be less integrated in intensity ratings with higher autistic traits. Future studies should test whether facial muscle activity, and physiological signals in general, are correspondingly less predictive of perceiving emotionality in others in individuals on the autism spectrum, and whether training interoceptive abilities might facilitate the interpretation of emotional expressions.

Exploring psychosomatic congruence: The effect of focusing on body parts as a body-oriented mentalization process

Background/Objective

: Patients with somatic symptoms are considered to have a deficiency in body-oriented mentalization; that is, the ability to perceive and interpret bodily sensations in relation to psychological states. We introduce the novel concept of psychosomatic congruence-the alignment of physical sensations with cognition and emotional states, which leads to behaviors that synchronize physical manifestations with emotional experiences and internal reflections. Despite its clinical relevance, this concept has not been empirically examined. Three experiments investigated the effects of psychosomatic congruence on the mental content of associations, autobiographical memories, and the accessibility of negative-related words. Grounded in theories of embodied cognition and interoception, we hypothesized that psychosomatic congruence could be facilitated through an initiated interoceptive task.

Methods

: Three pre-registered experiments involving 318 participants were conducted. Participants were asked to identify and label their most pleasant and unpleasant body parts, and then engaged in tasks involving associations with neutral words, memory retrieval, and the accessibility of negative-related words under varying conditions of mortality salience.

Results

: Focusing on the most pleasant body part, as compared to the most unpleasant, led to more positive associations with neutral words, enhanced positive memory retrieval, and reduced accessibility of negatively related words.

Conclusions

: These findings provide evidence that initiating an interoceptive task by focusing attention on body parts can induce congruent mental content. They offer insights into body-oriented mentalization and suggest that emotional distress may potentially be regulated by deliberately focusing on pleasant body parts.

Case report: Short-term psychotherapy for alexithymia in a patient with generalized anxiety disorder

Alexithymia is common among patients with generalized anxiety disorder (GAD) and may negatively affect the efficacy of treatment. This case report described a sole short-term psychotherapy focusing on alexithymia for a GAD patient. The intervention extends over 3 weekly 50-minute sessions and incorporates components of: (a) understanding the basic categories of emotions and the importance of processing them consciously and building one's own vocabulary of emotions; (b) developing skills in identifying and labeling emotions and learning to register both positive and negative emotions in daily life; (c) observing and interpreting emotion-related body sensations and learning to get in touch with, be empathetic to, and take care of one's own inner feelings in daily life. The Hamilton Rating Scale for Depression (HRSD), Hamilton Anxiety Rating Scale (HAMA), and Toronto Alexithymia Scale (TAS) were used to evaluate depression, anxiety, and alexithymia before and after the sessions. The results suggested that the treatment was not only effective in reducing alexithymia helping the patient to clarify, identify and describe her feelings, but also effective in reducing anxiety and depression.

The relationship of personality, alexithymia, anxiety symptoms, and odor awareness: a mediation analysis

OBJECTIVE

Personality, emotions, and olfaction exhibit partial anatomical overlap in the limbic system structure, establishing potential mechanisms between personality, affective disorders, and olfactory-related aspects. Thus, this study aims to investigate the associations among the Big Five personality traits, alexithymia, anxiety symptoms, and odor awareness.

METHODS

A total of 863 college participants were recruited for this study. All participants completed the Chinese Big Five Personality Inventory-15, the Odor Awareness Scale (OAS), the Toronto Alexithymia Scale-20, and the Generalized Anxiety Disorder Screener-7. Structural equation modeling was employed to examine the hypothesized mediated model.

RESULTS

The findings revealed the majority of significant intercorrelations among the dimensions of the Big Five personality traits, alexithymia, anxiety symptoms, and OAS (|r| = 0.072-0.567, p < 0.05). Alexithymia and anxiety symptoms exhibited a serial mediation effect between neuroticism and OAS (95%CI[0.001, 0.014]), conscientiousness and OAS (95%CI[-0.008, -0.001]), and extraversion and OAS (95%CI[-0.006, -0.001]). Anxiety symptoms mediated the relationship between agreeableness and OAS (95%CI[-0.023, -0.001]) and between openness and OAS (95%CI [0.004, 0.024]).

CONCLUSION

The mediating roles of alexithymia and anxiety symptoms between the Big Five personality traits and odor awareness support the idea of a certain level of association among personality, emotions, and olfaction, with the underlying role of the limbic system structure. This enhances our understanding of personality, emotions, and olfaction and provides insights for future intervention measures for affective disorders and olfactory dysfunctions.

Is Interoception Deficit Linking Alexithymia and Eating Spectrum Symptoms? Study on a Non-Clinical Sample of Young Adults

We investigated if interoceptive deficits could be the link between alexithymic traits and eating spectrum manifestations in a non-clinical sample. One-hundred sixty-one young adults (mean age: 23.2 ± 2.4 years) were evaluated with the Toronto Alexithymia Scale-20 (TAS-20), the Interoceptive Accuracy Scale (IAS), the Interoceptive Confusion Questionnaire (ICQ), and the Eating Attitudes Test-26 (EAT-26). Questionnaires were administered with an online procedure (Microsoft Form, Office 365 A1, Pisa, Italy) (Study Protocol #0012005/2023). We compared ICQ, IAS, and TAS-20 scores in subjects who met the threshold for a potential eating spectrum disorder according to EAT-26 scores ≥ 20 (n = 27) vs. subjects who scored <20 (n = 134), with an ANCOVA corrected for 'age' and 'gender'. Subjects with EAT-26 ≥ 20, scored significantly higher at ICQ (54.4 ± 13.2 vs. 50.2 ± 6.8; p = 0.011), TAS-20 'Total Score' (60.8 ± 11.9 vs. 58.1 ± 9.2; p = 0.006), and TAS-20 'Identifying Feelings' (21.5 ± 7.6 vs. 17.3 ± 5.8; p = 0.0001). A binary logistic regression analysis, with EAT-26 scores < 20 vs. ≥20 as the dependent variable, and ICQ, IAS, TAS-20 total scores and dimensions, age, and gender (categorical) as covariates, showed that the only variable predicting eating spectrum symptomatology was 'ICQ Total Score' (OR = 1.075, 95% CI: 1.016-1.139; p = 0.013). Interoceptive confusion was the dimension linking the occurrence of alexithymic traits and eating spectrum manifestations.

Soreness Reminds Me of Grief: Patients With Chronic Pain Show Less Differentiated Representations of Emotional Feelings and Bodily States

People experience similarities between emotional feelings and bodily states on a daily basis, but both the magnitude and pervasiveness of this experiential similarity vary across individuals. Inspired by previous findings that chronic pain (CP) is characterized by strengthened pain-affect coupling and reduced interoceptive accuracy, we conducted 2 cross-sectional studies to examine whether patients with CP would exhibit less differentiated perception and mental representation of emotional feelings and bodily states. In study 1 (N = 500), patients with CP and healthy controls (HCs) completed a self-report questionnaire that asked explicitly about the perceived similarity between 5 basic emotion categories and a series of bodily states. In study 2 (N = 73), a specially designed false memory test was administered to examine whether patients with CP would have reduced differentiation of concepts of negative emotion and somatic distress. We found that patients with CP perceived greater and more pervasive similarities between emotional feelings and bodily states, as indicated by higher questionnaire scores and denser, less specialized bipartite emotion-body networks, both associated with lower subjective interoceptive accuracy. Furthermore, patients with CP formed false memories of negative emotion words (eg, grief) more readily than HCs after memorizing somatic distress words (eg, soreness), as if they represented negative emotion and somatic distress as a single, enmeshed semantic category. Our findings extend previous literature by demonstrating reduced discrimination between emotional and bodily experiences in CP that is not restricted to pain-related emotional and sensory experiences and may be related to a fundamentally less differentiated interoception. PERSPECTIVES: This study shows that patients with chronic pain have a profoundly less differentiated perception and implicit conceptualization of emotional feelings and bodily states, which appears to be associated with altered interoception. These findings may provide new perspectives on why they often experience a stronger pain-affect coupling.

Identifying and regulating emotions after acquired brain injury: the role of interoceptive sensibility

Introduction

Interoceptive deficits are associated with difficulties in identifying and regulating emotions. However, research on interoception after acquired brain injury (ABI) is scarce, and its relationship with emotional difficulties in this population is unknown. This study aimed to (1) examine differences in self-reported alexithymia, performance-based emotional awareness, emotion regulation, depression, and interoceptive sensibility between ABI and control individuals; and (2) analyze the role of adaptive interoceptive dimensions in these emotional processes after ABI.

Methods

Forty-three individuals with ABI and 42 matched control individuals completed the Multidimensional Assessment of Interoceptive Awareness-2, the Toronto Alexithymia Scale, the Levels of Emotional Awareness Scale, the Difficulties in Emotion Regulation Scale, and the Hospital Anxiety and Depression Scale.

Results

Compared to the control group, individuals with ABI showed reduced tendency to ignore unpleasant sensations increased severity of depressive symptoms, as well as tendencies to have greater difficulties in emotion regulation and lower emotional awareness. Additionally, interoceptive dimensions such as trusting, as well as not-distracting from and not-worrying about bodily sensations, played a relevant role in explaining lower alexithymia and difficulties in emotion regulation. Moreover, lower alexithymia and emotion dysregulation were related to less depressive symptoms. These relationships were invariant across ABI and control individuals.

Discussion

Although individuals with ABI may have different levels of emotional abilities compared to non-ABI individuals, the relationship patterns between interoceptive and emotional processes appear to be similar between the two groups. This study suggests the potential benefit of addressing both interoceptive and emotional difficulties in treatments targeting such prevalent sequelae of ABI as depressive symptoms.

What is the relationship between alexithymia and experiential avoidance? A latent analysis using three alexithymia questionnaires

Alexithymia is a clinically relevant personality trait characterized by poor emotional awareness and associated with several psychological and physical health concerns. Individuals with high alexithymia tend to engage in experiential avoidance and this may mediate psychological distress. However, little is known about what specific processes of experiential avoidance are involved, and the nature of the relation between alexithymia, experiential avoidance, and psychological distress remains unclear at a latent construct level. To examine this relationship at the latent construct level, a representative sample of 693 U.S. adults completed alexithymia (TAS-20, BVAQ, PAQ), general distress (DASS-21), multi-dimensional experiential avoidance (MEAQ), and general health (PROMIS-G-10) questionnaires. Structural equation modeling revealed that alexithymia significantly predicted experiential avoidance (β = 0.966, t = 82.383, p < .01), experiential avoidance significantly predicted general distress (β = 0.810, t = 2.017, p < .05), and experiential avoidance fully mediated the relationship between alexithymia and general distress (βindirect = -0.159, t = -0.398, p > .05). Correlations between alexithymia and experiential avoidance subfactors revealed a strong relationship to the repression and denial subfactor. Experiential avoidance is a promising target for clinical interventions, though longitudinal research is necessary to elucidate how the relationship between alexithymia and experiential avoidance unfolds over time.

Psychometric validation and refinement of the Chinese Interoceptive Accuracy Scale (IAS) in general population and patients with chronic pain

OBJECTIVE

Interoception plays an important role in psychological functioning and mental and physical health. Recent studies have highlighted the need to distinguish between different aspects of interoception in self-report measures, including subjective interoceptive accuracy and attention. However, there is currently no questionnaire available in Chinese to measure either of these aspects, especially in patients with chronic pain conditions. This paper presents a Chinese translation of the Interoceptive Accuracy Scale (IAS; Murphy et al., 2020).

METHODS

In three studies (N = 1166), we examined the factor structure and improved dimensionality of the Chinese IAS using factor analysis and item response theory models, compared its criterion validity in respondents with and without chronic pain, and examined its construct (convergent and discriminant) validity using network analysis approach.

RESULTS

We demonstrated that the Chinese IAS is essentially unidimensional and developed a refined short form (IAS-SF) with improved unidimensionality. Both the Chinese IAS and IAS-SF showed comparable criterion validity in respondents with and without chronic pain, and both showed acceptable construct validity.

CONCLUSION

Overall, the Chinese IAS and Chinese IAS-SF will be useful tools for researchers and clinicians interested in interoceptive processes in Chinese populations or cross-cultural settings, especially in pain research.

[Interoceptive difficulties in children and adolescents with severe form of somatic symptom disorder: A pilot study with nineteen participants]

INTRODUCTION

Despite the high rate of somatic symptom disorder (TSS) in the pediatric population, etiological mechanisms remain poorly understood. Previous studies conducted in youths with anxiety, eating disorder, or autistic disorder support a relation between difficulties in the perception of sensory signals (i.e., interoception) and difficulties in identifying emotions.

METHOD

A cross-sectional study was carried out at the University Hospital of Amiens-Picardie in 19 young people aged 9 to 17 hospitalized in the pediatric ward for TSS. A mental heartbeat tracking task was used to assess interoceptive accuracy, awareness and sensibility. The Porges Body Perception Questionnaire (PBPQ) was used to assess interoceptive attention. Other questionnaires were used to assess associated clinical dimensions such as depression, anxiety, emotional dysregulation and alexithymia.

RESULTS

The mean interoceptive accuracy score was lower in TSS subjects compared to expected scores in the general population (33% error vs. 20%). A statistically significant correlation was found between, on the one hand, interoceptive sensibility and the "avoidance" subscore of the ECAP (r=0.51) and, on the other hand, between interoceptive awareness and the total score of the Child Depression Inventory (r=0.51). A significant relationship was found between the PBPQ scale total score and the Children-Toronto Alexithymia Scale total score (r=0.42), in particular with the "difficulty expressing emotions" subscore (r=0.62).

CONCLUSION

This study confirms that interoceptive difficulties occur in young patients with severe TSS. Our finding adds empirical evidence supporting the relations between interoceptive difficulties, alexithymia and somatic symptoms in children and adolescents.

Psychological interventions for interoception in mental health disorders: A systematic review of randomized-controlled trials

Disturbed interoception (i.e., the sensing, awareness, and regulation of internal body signals) has been found across several mental disorders, leading to the development of interoception-based interventions (IBIs). Searching PubMed and PsycINFO, we conducted the first systematic review of randomized-controlled trials (RCTs) investigating the efficacy of behavioral IBIs at improving interoception and target symptoms of mental disorders in comparison to a non-interoception-based control condition [CRD42021297993]. Thirty-one RCTs fulfilled inclusion criteria. Across all studies, a pattern emerged with 20 (64.5%) RCTs demonstrating IBIs to be more efficacious at improving interoception compared to control conditions. The most promising results were found for post-traumatic stress disorder, irritable bowel syndrome, fibromyalgia and substance use disorders. Regarding symptom improvement, the evidence was inconclusive. The IBIs were heterogenous in their approach to improving interoception. The quality of RCTs was moderate to good. In conclusion, IBIs are potentially efficacious at improving interoception for some mental disorders. In terms of symptom reduction, the evidence is less promising. Future research on the efficacy of IBIs is needed.

The new measures of interoceptive accuracy: A systematic review and assessment

Conscious interoception, the perception of internal bodily states, is thought to contribute to fundamental human abilities (e.g., decision-making and emotional regulation). One of its most studied dimensions is interoceptive accuracy: the objective capacity to detect internal bodily signals. In the past few years, several labs across the world have started developing new tasks aimed at overcoming limitations inherent in classical measures of interoceptive accuracy. In this systematic review, we identified these tasks (since 2015) for the cardiac, respiratory, and gastrointestinal domains. For each identified task, we discuss their strengths and weaknesses, and make constructive suggestions for further improvement. In the general discussion, we discuss the (potentially elusive) possibility of reaching high validity in the measurement of interoceptive accuracy. We also point out that interoceptive accuracy may not be the most critical dimension for informing current theories, and we encourage researchers to investigate other dimensions of conscious interoception.

A multidimensional investigation of the relationship between skin-mediated somatosensory signals, emotion regulation and behavior problems in autistic children

Introduction

Autistic children may have abnormal sensory perception, emotion dysregulation and behavior problems. The aim of this cross-sectional study was to explore the relationship between skin-mediated somatosensory signals and emotion/behavior difficulties in autistic children and adolescents, in comparison typically developing peers (TDP).

Methods

Thirty-eight autistic children and adolescents and 34 TDP completed a multidimensional assessment consisting of the measurement of somatosensory thresholds of touch, pain and temperature, a task on emotion knowledge and parent-reported questionnaires on sensory reactivity, emotion regulation and behavior.

Results

Autistic children had higher pain sensitivity, less sensory reactive behaviors and more behavior problems than their TDP. In contrast to TDP, several somatosensory thresholds of autistic children correlated with emotion regulation and behavior problems.

Discussion

Sensory dysfunction may affect the development of emotional processing and behavior in autistic children and adolescents. This knowledge can lay the foundation for future studies on co-occurring alterations in corresponding neural networks and for the implementation of early interventions, including sensory rehabilitation therapy, for promoting regulated behaviors in autistic children and adolescents.

Alexithymia and Interoceptive Confusion in Covid-19 Pandemic Distress

Objective

Alexithymic traits are associated with the difficulty of perceiving 'non-affective interoceptive signals', and are related to a problematic management of stressful life events (SLEs). The main purpose of this study was to quantify the psychological response of the general population to COVID-19 pandemic stress and to evaluate potential correlations with the presence of 'alexithymic traits' and 'interoceptive confusion' (study protocol # 0077794/2022).

Method

175 subjects from general population were assessed with the Toronto-Alexithymia Scale (TAS-20), the Event-Revised Impact Scale (IES-R), the Interoceptive Accuracy Scale (IAS), and the Interoceptive Confusion Questionnaire (ICQ).

Results

a significant relationship emerged between alexithymic traits (assessed with the TAS-20), the ICQ 'interoceptive confusion', and the domain of 'hyper-arousal' as assessed with IES-R. Logistic regression model showed that ICQ-Total Score and IES-R 'hyper-arousal' domain were significantly correlated with TAS-20 total score, with DR value (R2 corrected) explaining the 36.8% of the variability (standard error: 10.7).

Conclusions

This study, albeit with the limitations of a cross-sectional experimental design with self-evaluation tools in a general population sample, showed a vulnerability to COVID-19 pandemic stress due to high levels of hyper-arousal in subjects with alexithymic traits and interoceptive confusion.

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.

Turkish Adaptation, Validity, and Reliability Study of Shitsu-Taikan-Sho (Alexisomia) Scale

Background

The Shitsu-Taikan-Sho (Alexisomia) Scale is a self-report scale for measuring alexisomia, defined as the difficulty in awareness and expression of somatic emotions or feelings. The scale is available in Japanese and Finnish versions. This research aims to examine the psychometric properties of the Turkish version of the Shitsu-Taikan-Sho (Alexisomia) Scale.

Methods

The study sample consists of 320 patients who applied to the outpatient clinic of consultation-liaison psychiatry. Participants completed the Sociodemographic Information Form, the Turkish version of the Shitsu-Taikan-Sho (Alexisomia) Scale, and the Toronto Alexithymia Scale. Internal consistency and test-retest reliability were used for reliability analyses. Exploratory factor analysis, confirmatory factor analysis, and co-validity analyses were used for validity analyses.

Results

According to the exploratory factor analysis results, a 3-factor, 18-item model for the Turkish version of the Shitsu-Taikan-Sho (Alexisomia) Scale explained 48.3% of the variance (Kaiser-Meyer-Olkin = 0.866; χ 2 = 1535.3, P < .001). Confirmatory factor analysis results indicated a good fit (χ 2 = 234.893; SD = 132; χ 2/SD = 1.779; CFI = 0.927; GFI = 0.923; RMSEA = 0.049). In the co-validity analysis, a significant correlation was found between Toronto Alexithymia Scale-20 and Turkish version of the Shitsu-Taikan-Sho (Alexisomia) Scale (r = 0.556, P < .001). Cronbach's alpha coefficient was 0.825 for the total score, 0.711 for lack of health management based on bodily emotions, 0.794 for difficulty in describing bodily emotions, and 0.775 for over adaptation. The interclass correlation coefficient between the 2 measures of Turkish version of the Shitsu-Taikan-Sho (Alexisomia) Scale was 0.883 (P < .001).

Conclusion

The Turkish adaptation of the Shitsu-Taikan-Sho (Alexisomia) Scale demonstrated adequate psychometric properties. It is an appropriate scale for evaluating the concept of alexisomia in the population of consultation-liaison psychiatry.

Conformity to masculine norms, interoceptive dysfunction, and changes in muscle dysmorphia symptoms

Muscle dysmorphia (MD) is a psychiatric illness characterized by preoccupation and compulsive behaviors to increase muscle size/definition. Despite its severity, few risk factors/mechanisms for MD have been identified. Conformity to masculine norms may be a MD risk factor. Furthermore, interoceptive dysfunction may facilitate MD. symptoms, as well as underlie relationships between conformity to masculine norms and MD symptoms. However, research has yet to test the mediating role of interoceptive dysfunction for said relationships. The current study tested if interoceptive dysfunction underlies relationships between conformity to masculine norms and MD symptoms among 269 US men who completed three surveys separated by one month that contained measures of focal constructs. Our sample was majority White, heterosexual, and non-Hispanic. A three-wave autoregressive mediation model was tested in which conformity to masculine norms predicted interoceptive dysfunction, which then predicted MD symptoms. Results indicated that conformity to specific masculine norms predicted both interoceptive dysfunction and MD symptoms over time. Furthermore, our hypothesized mediation pathways were not discovered. Conformity to masculine norms appears to be a risk factor for MD symptoms and interoceptive dysfunction. If clinicians can reduce rigid adherence to masculine stereotypes, this may increase connection with one's body and reduce subsequent MD symptoms.

Emotional Dysfunction and Interoceptive Challenges in Adults with Autism Spectrum Disorders

People with autism spectrum disorder (ASD) frequently show impaired sensory processing in different senses, including the interoceptive system. Recent findings suggest that interoception is a fundamental component of emotional experience and that impaired interoception is associated with alexithymia. This study aims to explore the association and interrelation between interoceptive confusion, alexithymia, and the capacity for emotional regulation among a sample of 33 adults with ASD compared to a control group of 35 adults with neurotypical development and its mutual impact. The participants answered a series of questionnaires addressing these three variables. The results showed (1) significant differences between the groups in all dimensions, with dysfunctional emotional regulation, impaired interoception, and alexithymia in the ASD group, (2) significant correlations between interoceptive confusion, emotional clarity, and alexithymia in the ASD group but only positive correlations between interoceptive confusion and alexithymia in the CG, and (3) that emotional clarity, alexithymia, and autism explain 61% of the variance in interoceptive confusion. These results are in line with previous studies and suggest that training interoceptive ability may enhance emotional clarity and reduce alexithymia among those diagnosed with ASD, with significant implications in the planning of treatment.

Neural representations of vicarious rewards are linked to interoception and prosocial behaviour

Every day we constantly observe other people receiving rewards. Theoretical accounts posit that vicarious reward processing might be linked to people's sensitivity to internal body states (interoception) and facilitates a tendency to act prosocially. However, the neural processes underlying the links between vicarious reward processing, interoception, and prosocial behaviour are poorly understood. Previous research has linked vicarious reward processing to the anterior cingulate gyrus (ACCg) and the anterior insula (AI). Can we predict someone's propensity to be prosocial or to be aware of interoceptive signals from variability in how the ACCg and AI process rewards? Here, participants monitored rewards being delivered to themselves or a stranger during functional magnetic resonance imaging. Later, they performed a task measuring their willingness to exert effort to obtain rewards for others, and a task measuring their propensity to be aware and use interoceptive respiratory signals. Using multivariate similarity analysis, we show that people's willingness to be prosocial is predicted by greater similarity between self and other representations in the ACCg. Moreover, greater dissimilarity in self-other representations in the AI is linked to interoceptive propensity. These findings highlight that vicarious reward is linked to bodily signals in AI, and foster prosocial tendencies through the ACCg.

The contribution of subliminal perceptions, dietary habits, and psychological traits to the perception of oral tingling and burning sensations

The tingling evoked by Sichuan pepper and the burning elicited by chili pepper constitutes the typical flavor of Sichuan cuisine and is a component of leisure food. Although factors affecting the burning sensation have extensively been studied, few studies have examined the factors of individual sensitivity, personality traits, and dietary habits that contribute to the perception of oral tingling sensation, which hinders the formulation of tingling products and the development of new products. In contrast, many studies have examined the factors influencing the burning sensation. In this web-based survey, 68 participants disclosed their dietary habits, liking for tingling and hot foods, and psychological traits. Individual sensitivity to the tingling and burning sensation produced by a range of Sichuan pepper oleoresin and capsaicin solutions was determined using rated differences from control, generalized labeled magnitude scale method and ranking test. The consistency score indicated the accuracy of individual ranking results while also providing an indirect response to the sensitivity of the participant to supra-threshold for burning or tingling. Individual ratings for medium Sichuan pepper oleoresin concentrations significantly correlated with the just noticeable difference (p < 0.01), and ratings for medium and high capsaicin concentrations correlated significantly with 6-n-propylthiouracil ratings (p < 0.01). Notably, the power exponent of burning was significantly correlated with the burning recognition threshold (p < 0.01), and the power exponent of tingling and burning were significantly correlated (r = 0.340, p < 0.05). There was a negative correlation between supra-threshold tingling and burning sensation perceptions and life satisfaction ratings. Further, intensity ratings for oral tingling and burning sensation did not always correspond with individual sensitivity indicators (e.g., recognition threshold, 6-n-propylthiouracil, just noticeable difference, and consistency score). Thus, this study provides new insight into establishing a sensory selection method for chemesthetic sensation panelists and theoretical guidelines for formulation design and in-depth analysis of popular tingling dishes and foods.

Depression mediates the relationship between alexithymia and obesity in the Northern Finland Birth Cohort 1966 (NFBC1966)

BACKGROUND

The fact that a complex relationship exists between alexithymia and body mass index (BMI) is well established, but the underlying mechanisms remain poorly understood. Here, we explore the relationship between alexithymia and depressive symptoms in relation to adiposity measures, including the direct and indirect effect of alexithymia and depressive symptoms on obesity over a 15-year time-period, in the Northern Finland Birth Cohort 1966 (NFBC1966).

METHODS

The study included individuals from the Northern Finland Birth Cohort 1966 (NFBC1966) who had available data for adiposity measures (body mass index and waist-to-hip ratio), alexithymia (measured by the 20-Item Toronto Alexithymia Scale: TAS-20), depressive symptoms (measured by the 13-item depression subscale of Hopkins Symptom Checklist: HSCL-13) at age of 31 years (n = 4773) and 46 years (n = 4431). Pearson's (r) correlation, and multiple linear regression were used to investigate the relationships between alexithymia, depressive symptoms, and adiposity measures. The potential mediating role of depressive symptoms was examined via Hayes' procedure (PROCESS).

RESULTS

Positive correlations were confirmed between adiposity measures (BMI and WHR) and the TAS-20 score (and its subscale), but not between obesity and HSCL-13 score. The strongest correlation was between the DIF (difficulty identifying feelings) subscale of the TAS-20 and HSCL-13 at both time points (31 y: r₍₃₀₁₃₎ = 0.41, p < 0.01, 46 y: r₍₃₀₁₃₎ = 0.43, p < 0.01). Depressive symptoms completely (z = 2.55 (±0.00003), p = 0.01) and partly (z = 2.16 (±0.0001), p = 0.03) mediated the alexithymia-obesity relationship over the 15-year time-period.

LIMITATIONS

Other psychological and environmental factors such as interoception, dietary intake and physical activities may also play a role as a potential mediating factor in alexithymia-obesity relationship.

CONCLUSIONS

Our findings provide additional insights of theoretical framework of depressive symptoms mediation effect in the relationship between alexithymia and obesity. Alexithymia and depression should, therefore, be considered in the design of future clinical obesity research.

Characterizing Interoceptive Differences in Autism: A Systematic Review and Meta-analysis of Case-control Studies

Interoception, the body's perception of its own internal states, is thought to be altered in autism, though results of empirical studies have been inconsistent. The current study systematically reviewed and meta-analyzed the extant literature comparing interoceptive outcomes between autistic (AUT) and neurotypical (NT) individuals, determining which domains of interoception demonstrate robust between-group differences. A three-level Bayesian meta-analysis compared heartbeat counting performance, heartbeat discrimination performance, heartbeat counting confidence ratings, and self-reported interoceptive attention between AUT and NT groups (15 studies; nAUT = 467, nNT = 478). Autistic participants showed significantly reduced heartbeat counting performance [g = - 0.333, CrI95% (- 0.535, - 0.138)] and higher confidence in their heartbeat counting abilities [g = 0.430, CrI95% (0.123, 0.750)], but groups were equivalent on other meta-analyzed outcomes. Implications for future interoception research in autism are discussed.

The relationship between alexithymia, interoception, and neural functional connectivity during facial expression processing in autism spectrum disorder

Neural processing differences of emotional facial expressions, while common in autism spectrum disorder (ASD), may be related to co-occurring alexithymia and interoceptive processing differences rather than autism per se. Here, we investigate relationships between alexithymia, interoceptive awareness of emotions, and functional connectivity during observation of facial expressions in youth (aged 8-17) with ASD (n = 28) compared to typically developing peers (TD; n = 37). Behaviorally, we found no significant differences between ASD and TD groups in interoceptive awareness of emotions, though alexithymia severity was significantly higher in the ASD group. In the ASD group, increased alexithymia was significantly correlated with lower interoceptive sensation felt during emotion. Using psycho-physiological interaction (PPI) analysis, the ASD group showed higher functional connectivity between the left ventral anterior insula and the left lateral prefrontal cortex than the TD group when viewing facial expressions. Further, alexithymia was associated with reduced left anterior insula-right precuneus connectivity and reduced right dorsal anterior insula-left ventral anterior insula connectivity when viewing facial expressions. In the ASD group, the degree of interoceptive sensation felt during emotion was positively correlated with left ventral anterior insula-right IFG connectivity when viewing facial expressions. However, across all participants, neither alexithymia nor interoceptive awareness of emotions predicted connectivity between emotion-related brain regions when viewing emotional facial expressions. To summarize, we found that in ASD compared to TD: 1) there is stronger connectivity between the insula and lateral prefrontal cortex; and 2) differences in interhemispheric and within left hemisphere connectivity between the insula and other emotion-related brain regions are related to individual differences in interoceptive processing and alexithymia. These results highlight complex relationships between alexithymia, interoception, and brain processing in ASD.

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.

Do alexithymia and negative affect predict poor sleep quality? The moderating role of interoceptive sensibility

OBJECTIVES

Emotion-related hyperarousal is an important core pathology of poor sleep. Studies investigating the interplay of alexithymia and affective experiences in determining sleep quality have yielded mixed results. To disentangle the inconsistency, this study examined the concurrent predictive power of alexithymia, and negative and positive affect, while incorporating interoceptive sensibility (IS) as a possible moderator.

METHODS

A sample of 224 (70.10% were female) participants completed the Toronto Alexithymia Scale, Positive and Negative Affect Schedule, Pittsburgh Sleep Quality Index, Multidimensional Assessment of Interoceptive Awareness (MAIA), and Marlowe-Crowne Social Desirability Scale (for controlling response bias) using paper and pencil. A two-stage cluster analysis of the MAIA was used to capture IS characteristics. Stepwise regression was conducted separately for each IS cluster.

RESULTS

A three-group structure for IS characteristics was found. Higher alexithymia was predictive of poor sleep quality in the low IS group, while higher negative affect predicted poor sleep quality in the moderate and high IS groups. Additionally, alexithymia and positive affect were significantly different in the three IS groups, while negative affect and sleep quality were not.

CONCLUSIONS

Emotion and cognitive arousal may impact sleep quality differently in individuals with different levels of internal focusing ability, depending on physiological versus emotional self-conceptualization. The implications on pathological research, clinical intervention, study limitations and future directions are discussed.

The modulation of acute stress on model-free and model-based reinforcement learning in gambling disorder

BACKGROUND AND AIMS

Experiencing acute stress is common in behavioral addictions such as gambling disorder. Additionally, like most substance-induced addictions, aberrant decision-making wherein a reactive habit-induced response (conceptualized as a Model-free [MF] in reinforcement learning) suppresses a flexible goal-directed response (conceptualized as a Model-based [MB]) is also common in gambling disorder. In the current study we investigated the influence of acute stress on the balance between habitual response and the goal-directed system.

METHODS

A sample of N = 116 problem gamblers (PG) and healthy controls (HC) performed an acute stress task - the Socially Evaluated Cold pressure task (SECPT) - or a control task. Self-reported stress and salivary cortisol were collected as measures of acute stress. Following the SECPT, participants performed the Two-Step Markov Task to account for the relative contribution of MB and MF strategies. Additionally, verbal working memory and IQ measures were collected to account for their mediating effects on the orchestration between MB/MF and the impact of stress.

RESULTS

Both groups had comparable baseline and stress-induced cortisol response to the SECPT. Non-stressed PG displayed lower MB learning than HC. MANOVA and regression analyses showed a deleterious effect of stress-induced cortisol response on the orchestration between MB and MF learning in HC but not in PG. These effects remained when controlling for working memory and IQ.

DISCUSSION AND CONCLUSIONS

We found an abnormal pattern of modulation of stress on the orchestration between MB and MF learning among PG. Several interpretations and future research directions are discussed.

Brain-heart interactions in the neurobiology of consciousness

Recent experimental evidence on patients with disorders of consciousness revealed that observing brain-heart interactions helps to detect residual consciousness, even in patients with absence of behavioral signs of consciousness. Those findings support hypotheses suggesting that visceral activity is involved in the neurobiology of consciousness, and sum to the existing evidence in healthy participants in which the neural responses to heartbeats reveal perceptual and self-consciousness. More evidence obtained through mathematical modeling of physiological dynamics revealed that emotion processing is prompted by an initial modulation from ascending vagal inputs to the brain, followed by sustained bidirectional brain-heart interactions. Those findings support long-lasting hypotheses on the causal role of bodily activity in emotions, feelings, and potentially consciousness. In this paper, the theoretical landscape on the potential role of heartbeats in cognition and consciousness is reviewed, as well as the experimental evidence supporting these hypotheses. I advocate for methodological developments on the estimation of brain-heart interactions to uncover the role of cardiac inputs in the origin, levels, and contents of consciousness. The ongoing evidence depicts interactions further than the cortical responses evoked by each heartbeat, suggesting the potential presence of non-linear, complex, and bidirectional communication between brain and heartbeat dynamics. Further developments on methodologies to analyze brain-heart interactions may contribute to a better understanding of the physiological dynamics involved in homeostatic-allostatic control, cognitive functions, and consciousness.

Self-Reported Body Awareness: Validation of the Postural Awareness Scale and the Multidimensional Assessment of Interoceptive Awareness (Version 2) in a Non-clinical Adult French-Speaking Sample

Body awareness refers to the individual ability to process signals originating from within the body, which provide a mapping of the body's internal landscape (interoception) and its relation with space and movement (proprioception). The present study aims to evaluate psychometric properties and validate in French two self-report measures of body awareness: the Postural Awareness Scale (PAS), and the last version of the Multidimensional Assessment of Interoceptive Awareness questionnaire (version 2, MAIA-2). We collected data in a non-clinical, adult sample (N = 308; 61% women, mean age 35 ± 12 years) using online survey, and a subset of the original sample (n = 122; 62% women, mean age 44 ± 11 years) also completed the retest control. Factor analyses and reliability analyses were conducted. Construct validity of the PAS and the MAIA-2 were examined by testing their association with each other, and with self-report measures of personality (Big Five Inventory), alexithymia (Toronto Alexithymia Scale) and dispositional trait mindfulness (Freiburg Mindfulness Inventory). Factor analyses of the PAS supported the same two-factor structure as previously published versions (in other languages). For the MAIA-2, factor analyses suggested that a six-factor structure, excluding Not-Worrying and Not-Distracting factors, could successfully account for a common general factor of self-reported interoception. We found satisfactory internal consistency, construct validity, and reliability over time for both the PAS and the MAIA-2. Altogether, our findings suggest that the French version of the PAS and the MAIA-2 are reliable self-report tools to assess both components of body awareness (proprioception and interoception dimension, respectively).

Interoceptive pathways to understand and treat mental health conditions

An increasing recognition that brain and body are dynamically coupled has enriched our scientific understanding of mental health conditions. Peripheral signals interact centrally to influence how we think and feel, generating our sense of the internal condition of the body, a process known as interoception. Disruptions to this interoceptive system may contribute to clinical conditions, including anxiety, depression, and psychosis. After reviewing the nature of interoceptive disturbances in mental health conditions, this review focuses on interoceptive pathways of existing and putative mental health treatments. Emerging clinical interventions may target novel peripheral treatment mechanisms. Future treatment development requires forward- and back-translation to uncover and target specific interoceptive processes in mental health to elucidate their efficacy relative to interventions targeting other factors.

Alexithymia in autism: cross-sectional and longitudinal associations with social-communication difficulties, anxiety and depression symptoms

BACKGROUND

Alexithymia (difficulties in identifying and describing emotion) is a transdiagnostic trait implicated in social-emotional and mental health problems in the general population. Many autistic individuals experience significant social-communication difficulties and elevated anxiety/depression and alexithymia. Nevertheless, the role of alexithymia in explaining individual variability in the quality/severity of social-communication difficulties and/or anxiety and depression symptoms in autism remains poorly understood.

METHODS

In total, 337 adolescents and adults (autism N = 179) were assessed for alexithymia on the Toronto Alexithymia Scale and for social-communication difficulties, anxiety and depression symptoms. A total of 135 individuals (autism N = 76) were followed up 12-24 months later. We used regression models to establish cross-sectional and longitudinal associations between alexithymia, social-communication difficulties, anxiety and depression symptoms.

RESULTS

Autistic individuals reported significantly higher alexithymia than comparison individuals (p < 0.001, r effect size = 0.48), with 47.3% of autistic females and 21.0% of autistic males meeting cut-off for clinically relevant alexithymia (score ⩾61). Difficulties in describing feelings were particularly associated with current self-reported social-communication difficulties [p < 0.001, β = 0.57, 95% confidence interval (CI) 0.44-0.67] and predicted later social-communication difficulties (p = 0.02, β = 0.43, 95% CI 0.07-0.82). Difficulties in identifying feelings were particularly associated with current anxiety symptom severity (p < 0.001, β = 0.54, 95% CI 0.41-0.77) and predicted later anxiety (p = 0.01; β = 0.31, 95% CI 0.08-0.62).

CONCLUSIONS

Our findings suggest that difficulties in identifying v. describing emotion are associated with differential clinical outcomes in autism. Psychological therapies targeting emotional awareness may improve social-communication and anxiety symptoms in autism, potentially conferring long-term benefits.

Predictors of the Sense of Embodiment of a Female Victim of Sexual Harassment in a Male Sample Through 360-Degree Video-Based Virtual Reality

The sense of embodiment refers to the set of sensations related to having (i.e., ownership), being located in (i.e., location), and controlling (i.e., agency) a virtual body. Recently, 360-degree video-based Virtual Reality (VR) has been used to manipulate the sense of embodiment, generating the body-swap illusion, that is, the illusionary switch from the real body to a virtual one. However, the psychological mechanisms involved in this illusion are still unknown. The present study is a secondary analysis of the study by Ventura et al. (2021) investigating the feasibility of 360-degree video to induce the body swap from a male's real body to a female virtual body in a sexual harassment virtual environment. In addition, the study explores whether the sense of presence and psychological trait variables related to sexual harassment (i.e., machismo, chivalry, alexithymia, empathic abilities) predict the illusion of owning the body of a female victim of sexual harassment. Forty-four men participated in the study, and the results indicate that the 360-degree video is able to induce the body-swap illusion for location and ownership, but not for agency. Multiple regression analyses showed that the sense of presence was a predictor of the three dimensions of embodiment, but specific psychological traits (i.e., low scores on machismo, high scores on difficulties expressing feelings, and high scores on perspective taking) were also predictor variables of experiencing a greater sense of location and agency in the female virtual body. This study shows that both technological issues and participants' psychological traits are involved in the experience of the body-swap illusion in a sexual harassment scenario using 360-degree video-based VR.

Investigating the sense of agency and its relation to subclinical traits using a novel task

Tasks measuring the sense of agency often manipulate the predictability of action outcomes by introducing spatial deviation. However, the extent to which spatial predictability of an outcome influences the sense of agency when spatial deviation is controlled for remains untested. We used a novel task to investigate the effect of several factors (action-outcome contingency, spatial deviation, and spatial predictability when controlling for spatial deviation of action outcomes) on the sense of agency. We also investigated trait predictors of metacognition of agency-the degree to which participants' confidence in their agency judgements corresponds to the accuracy of those judgements. Initial and replication samples completed contingency, deviation, and predictability versions of the task. Across samples, participants' sense of agency was impacted by action-outcome contingency and spatial deviation of action outcomes. Manipulation of the spatial predictability of action outcomes did not reliably impact the sense of agency. Metacognition of agency was related to alexithymic traits-higher alexithymia scores were associated with reduced metacognition of agency.

The process of emotion identification: Considerations for psychiatric disorders

Emotional regulation is important for mental health and behavioral regulation. A relevant precursor to emotional regulation may involve identification of one's emotions. Here, we propose a model of seven components that may provide a foundation for emotion identification. These factors include baseline mood, monitoring, physiological responses, interoception, past personal experiences regarding emotions/metacognition, context, and labeling. We additionally examine how deficits in different components may contribute to the concept of alexithymia, which is defined by difficulty identifying and describing one's own emotions. Ultimately, we explore how the model may support a relationship between specific psychiatric disorders and alexithymia. The proposed model may help explain emotional identification impairment in multiple psychiatric disorders and guide future research and treatment development efforts.

A network analysis of interoception, self-awareness, empathy, alexithymia, and autistic traits

Altered interoception has been consistently found in people with autism spectrum disorder (ASD), and this impairment may contribute to social cognitive dysfunctions. However, little is known regarding the intercorrelations between interoceptive sensibility, autistic, alexithymic, empathic, and self-related traits. We recruited 1360 non-clinical college students and adults to investigate the complex inter-relationship between these variables using network analysis. The resultant network revealed patterns connecting autistic traits to interoceptive sensibility, empathy, alexithymia, and self-awareness, with reasonable stability and test-retest consistency. The node of alexithymia exhibited the highest centrality and expected influence. As revealed by the network comparison test, networks constructed in high- and low-autistic subgroups were comparable in global strength and structure. Our findings suggested that alexithymia serves as an important node, bridging interoceptive deficits, self-awareness, and empathic impairments of autism spectrum disorder. The co-morbidity of alexithymia should be considered carefully in future studies of interoceptive impairments and social deficits in ASD.

Decreased interoceptive accuracy in children with autism spectrum disorder and with comorbid attention deficit/hyperactivity disorder

Interoception refers to the awareness of internal physiological state. Several previous studies reported that people with autism spectrum disorders (ASD) and adults with attention-deficit/hyperactivity disorder (ADHD) have diverse patterns of interoception, but the extent of literature is limited and inconsistent. This study aimed to investigate the interoceptive accuracy (IA) in children with ASD, children with comorbid ASD and ADHD, and typically developing (TD) children with high and low levels of autistic traits. We administered the eye-tracking interoceptive accuracy task (EIAT) to 30 children with ASD, 20 children with comorbid ASD and ADHD, and 63 TD controls with high and low levels of autistic traits. Parent-report scales concerning ASD and ADHD symptoms were collected. ASD children with and without comorbid ADHD both exhibited lower IA than TD children. Reduced IA was also found in TD children with high-autistic traits relative to those with low-autistic traits. IA was negatively correlated with autistic and ADHD symptoms. Atypical cardiac interoception could be found in children with ASD. Difficulties in sensing and comprehending internal bodily signals in childhood may be related to both ASD and ADHD symptoms.