Improving heartbeat perception in patients with medically unexplained symptoms reduces symptom distress

How might interoceptive accuracy training work?

With growing interest in interoceptive training to enhance the perception of internal bodily signals, there is a need to consider the mechanisms by which training may improve performance on tests of interoceptive accuracy (i.e., tests designed to measure how well signals from the body can be perceived). In this brief paper we use the example of cardiac interoceptive accuracy training to outline several possible mechanisms by which such training may result in improvement on tests of cardiac interoceptive accuracy. We show that under many of these mechanisms, evidence of improvement on tasks that claim to measure cardiac interoceptive accuracy does not reflect improvement in the perception of cardiac signals. We provide several recommendations to mitigate the potential influence of factors unrelated to interoceptive accuracy, enabling it to be determined that an improvement in interoceptive accuracy has occurred following training.

Interoception and mental health in middle-aged and elderly adults: A systematic review and meta-analysis

BACKGROUND

Recent studies have identified interoceptive dysfunction as a critical biomarker for emotional disorders. It is well-established that aging correlates with a deterioration in interoceptive capabilities, which consequently affects emotional processing dynamics.

METHODS

This study performed a systematic review and meta-analysis to evaluate the associations between interoceptive variants and mental health in middle-aged and elderly adults. Three English databases, including PubMed, Web of Science, and Medline (via EBSCO), were electronically searched from inception through December 2023. The study quality and meta-analysis were performed using the MMAT and RevMan 5.4 software.

RESULTS

A total of 21 studies were included in this systematic review, and data from 14 studies were used in the meta-analysis. Favorable associations were seen between interoception and depression (pooled r = -0.11 (95CI%: -0.19 to -0.03), z = 2.72, p = 0.006, I2= 0 %), alexithymia (pooled r = -0.25 (95CI%: -0.35 to -0.16), z = 4.84, p < 0.001, I2= 31 %), and emotion regulation (pooled r = 0.30 (95CI%: 0.18-0.41), z = 4.63, p < 0.001, I2= 33 %). Interoception showed no significant correlation with other mental health outcomes.

CONCLUSION

This systematic review and meta-analysis underscore the importance of interoception in understanding the underlying neural mechanisms of depression, alexithymia, and emotion regulation in middle-aged and older adults. Interoceptive training could also potentially serve as an effective strategy for promoting mental health within this demographic.

Predictive role of exteroceptive and interoceptive bodily dimensions to schizotypal personality traits

The phenomenological approach to schizophrenia emphasizes the role of bodily experiences in the onset and manifestation of positive, negative and disorganized psychotic symptoms. According to the dimensional approach to psychosis, there exists a continuum ranging from individuals with low levels of schizotypy to diagnosed schizophrenia patients, with schizotypy encompassing positive-like, negative-like, and disorganized-like symptoms of schizophrenia. Empirical evidence suggests that along this continuum, both exteroceptive (external sensory) and interoceptive (internal bodily) dimensions might be distorted. Understanding the contribution of these bodily dimensions in the manifestation of psychotic symptoms, even in schizotypy, might help target early interventions for individuals at risk of developing psychotic disorders. This study investigated the potential contribution of exteroceptive and interoceptive bodily dimensions to schizotypal personality traits, such as cognitive-perceptual traits (positive-like symptoms), interpersonal traits (negative-like symptoms), and disorganization traits (disorganized-like symptoms). Partial Least Squares Regression was used to integrate several bodily dimensions to understand their impact on schizotypy, revealing specific and non-specific contributions of exteroceptive and interoceptive dimensions to different traits. In particular, exteroceptive bodily dimensions generally predicted all schizotypal traits, with specific associations to positive-like symptoms, while interoceptive dimensions mostly predicted interpersonal-like and disorganized-like symptoms. These results suggest a difference in how exteroceptive and interoceptive bodily dimensions contribute to the three schizotypal traits. This highlights specific aspects of interoceptive and exteroceptive body representations that could serve as targets for early intervention. Particularly, interoception emerges as a potential prodromal marker, suggesting that early intervention in this area could be crucial.

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.

Interoceptive training with real-time haptic versus visual heartbeat feedback

The perception of signals from within the body, known as interoception, is increasingly recognized as a prerequisite for physical and mental health. This study is dedicated to the development of effective technological approaches for enhancing interoceptive abilities. We provide evidence of the effectiveness and practical feasibility of a novel real-time haptic heartbeat supplementation technology combining principles of biofeedback and sensory augmentation. In a randomized controlled study, we applied the developed naturalistic haptic feedback on a group of 30 adults, while another group of 30 adults received more traditional real-time visual heartbeat feedback. A single session of haptic, but not visual heartbeat feedback resulted in increased interoceptive accuracy and confidence, as measured by the heart rate discrimination task, and in a shift of attention toward the body. Participants rated the developed technology as more helpful and pleasant than the visual feedback, thus indicating high user satisfaction. The study highlights the importance of matching sensory characteristics of the feedback provided to the natural bodily prototype. Our work suggests that real-time haptic feedback might be a superior approach for strengthening the mind-body connection in interventions for physical and mental health.

Mechanistic studies in pathological health anxiety: A systematic review and emerging conceptual framework

BACKGROUND

Pathological health anxiety (PHA) (e.g., hypochondriasis and illness anxiety disorder) is common in medical settings and associated with increased healthcare costs. However, the psychological and neurobiological mechanisms contributing to the development and maintenance of PHA are incompletely understood.

METHODS

We performed a systematic review to characterize the mechanistic understanding of PHA. PubMed, PsycINFO, and Embase databases were searched to find articles published between 1/1/1990 and 12/31/2022 employing a behavioral task and/or physiological measures in individuals with hypochondriasis, illness anxiety disorder, and PHA more broadly.

RESULTS

Out of 9141 records identified, fifty-seven met inclusion criteria. Article quality varied substantially across studies, and was overall inadequate. Cognitive, behavioral, and affective findings implicated in PHA included health-related attentional and memory recall biases, a narrow health concept, threat confirming thought patterns, use of safety-seeking behaviors, and biased explicit and implicit affective processing of health-related information among other observations. There is initial evidence supporting a potential overestimation of interoceptive stimuli in those with PHA. Neuroendocrine, electrophysiology, and brain imaging research in PHA are particularly in their early stages.

LIMITATIONS

Included articles evaluated PHA categorically, suggesting that sub-threshold and dimensional health anxiety considerations are not contextualized.

CONCLUSIONS

Within an integrated cognitive-behavioral-affective and predictive processing formulation, we theorize that sub-optimal illness and health concepts, altered interoceptive modeling, biased illness-based predictions and attention, and aberrant prediction error learning are mechanisms relevant to PHA requiring more research. Comprehensively investigating the pathophysiology of PHA offers the potential to identify adjunctive diagnostic biomarkers and catalyze new biologically-informed treatments.

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.

Spontaneous eye blinking during an auditory, an interoceptive and a visual task: The role of the sensory modality and the attentional focus

Previous evidence suggested that spontaneous eye blinking changes as a function of the attentional focus. In particular, eye blink rate (EBR) tends to increase when attention is directed to internal versus environmental processing. Most studies on this issue compared eye blinking during visual and mental imagery tasks, and interpreted the increase in EBR as a mechanism to focus cognitive resources on internal processing by disengaging attention from interfering information. However, since eye blinking also depends on the sensory modality of the task, the findings might be influenced by a modality-specific effect. In the present Registered Report we aim at investigating whether the environmental versus internal attentional focus can affect spontaneous blinking behaviour in non-visual tasks as well, in conditions where visual stimuli are not relevant. In a within-subject design, healthy participants performed an interoceptive task (i.e., heartbeat counting) and an auditory task in which pre-recorded heartbeats were presented aurally; during both tasks irrelevant visual stimuli were also presented. In a further control condition with the same auditory and visual stimuli, the participants were required to focus their attention on visual stimuli. Participants' EBR was recorded during each task by means of an eye-tracking system. We found that, although the interoceptive task was more difficult than the auditory and visual tasks, participants' EBR decreased by a comparable level in all tasks with respect to a rest condition, with no differences between internal versus environmental conditions. The present findings do not support the idea that EBR is modulated by an internal versus external focus of attention, at least in presence of controlled visual stimulation.

Lower gastric sensitivity in quiescent inflammatory bowel disease than in irritable bowel syndrome

OBJECTIVE

Visceral hypersensitivity is considered a key symptom in inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS), both of which seriously affect health-related quality of life (HrQoL). Previous findings are mostly based on invasive procedures that may interfere with the assessment of visceral perception. The current study, therefore, investigates whether IBD and IBS are characterized by altered perception of 'natural' gastric distensions ('interoception').

METHODS

Twenty IBD patients in remission (13 Crohn's disease, 7 ulcerative colitis), 12 IBS patients, and 20/12 matched healthy control (HC) individuals, respectively, underwent the water load test, in which they could drink ad libitum until the subjective thresholds of satiation (stage 1) and fullness (stage 2) were reached. Gastric motility was assessed using electrogastrography.

RESULTS

IBD patients drank significantly more water until satiation than IBS patients, whereas no differences between patients and HC groups were observed. Electrogastrographic patterns were comparable between groups, suggesting no pathologies in gastric motility in IBD or IBS. The amount of water consumed until satiation negatively correlated with HrQoL related to bowel symptoms in IBD patients, but was positively associated with emotional well-being in IBS patients.

CONCLUSION

Our findings implicate relative gastric hypersensitivity in IBS, and relative hyposensitivity in IBD patients, which are both related to specific HrQoL aspects.

Puzzled by dysfunctional breathing disorder(s)? Consider the Bayesian brain hypothesis!

There is currently growing clinical concern regarding dysfunctional breathing disorder(s) (DBD), an umbrella term for a set of multidimensional clinical conditions that are characterized by altered breathing pattern associated with a variety of intermittent or chronic symptoms, notably dyspnea, in the absence or in excess of, organic disease. However, several aspects of DBD remain poorly understood and/or open to debate, especially the inconsistent relationship between the array of experienced symptoms and their supposedly underlying mechanisms. This may be partly due to a more general problem, i.e., the prevailing way we conceptualize symptoms. In the present article, after a brief review of the different aspects of DBD from the current perspective, I submit a call for considering DBD under the innovating perspective of the Bayesian brain hypothesis, i.e., a potent and novel model that fundamentally changes our views on symptom perception.

What I see and what I feel: the influence of deceptive visual cues and interoceptive accuracy on affective valence and sense of effort during virtual reality cycling

Background

How we feel during exercise is influenced by exteroceptive (e.g., vision) and interoceptive (i.e., internal body signals) sensory information, and by our prior experiences and expectations. Deceptive visual cues about one's performance during exercise can increase work rate, without negatively impacting affective valence (good/bad responses) or perceived exertion. However, what is less understood is whether the perception of the exercise experience itself can be shifted, if work rate is held constant. Here we aimed to investigate whether deceptive vision-via illusory hills in a virtual reality (VR) cycling experience-alters affective valence and perceived exertion when physical effort is controlled. We also evaluated whether the accuracy with which one detects interoceptive cues influences the extent to which deceptive visual information can shift exercise experiences.

Methods

A total of 20 participants (10 female; 30.2 ± 11.2 yrs) completed three VR cycling conditions each of 10-min duration, in a randomised, counterbalanced order. Pedal resistance/cadence were individualised (to exercise intensity around ventilatory threshold) and held constant across conditions; only visual cues varied. Two conditions provided deceptive visual cues about the terrain (illusory uphill, illusory downhill; resistance did not change); one condition provided accurate visual cues (flat terrain). Ratings of affective valence (Feeling Scale) and of perceived exertion (Borg's RPE) were obtained at standardised timepoints in each VR condition. Interoceptive accuracy was measured via a heartbeat detection test.

Results

Linear mixed effects models revealed that deceptive visual cues altered affective valence (f2 = 0.0198). Relative to flat terrain, illusory downhill reduced affective valence (Est = -0.21, p = 0.003), but illusory uphill did not significantly improve affective valence (Est = 0.107, p = 0.14). Deceptive visual cues altered perceived exertion, and this was moderated by the level of interoceptive accuracy (Condition-Interoception interaction, p = 0.00000024, f2 = 0.0307). Higher levels of interoceptive accuracy resulted in higher perceived exertion in the illusory downhill condition (vs flat), while lower interoceptive accuracy resulted in lower perceived exertion in both illusory hill conditions (vs flat) and shifts of greater magnitude.

Conclusions

Deceptive visual cues influence perceptual responses during exercise when physical effort does not vary, and for perceived exertion, the weighting given to visual exteroceptive cues is determined by accuracy with which interoceptive cues are detected. Contrary to our hypotheses, deceptive visual cues did not improve affective valence. Our findings suggest that those with lower levels of interoceptive accuracy experience most benefit from deceptive visual cues, providing preliminary insight into individualised exercise prescription to promote positive (and avoid negative) exercise experiences.

Increasing familiarity with the heartbeat counting task does not affect performance

BACKGROUND

Interoception is typically defined as the processing and perception of internal signals. A common evaluation of interoceptive abilities is the heartbeat counting task, during which participants count their heartbeats over a period of time. It has been argued recently, however, that performance in this task may reflect processes other than cardiac sensation.

OBJECTIVE

This study aimed to: 1) observe heartbeat counting task performance changes across multiple repetitions of the task; and 2) compare performance in the heartbeat counting task with that for a visual counting task to investigate generalised propensities for how uncertain stimuli are reported.

METHODS

Seventy-nine healthy participants performed seven blocks each of the heartbeat and visual counting tasks. Scores for each of the tasks were compared across blocks to identify any change in performance. Performance in the two tasks was then correlated. The study was preregistered at https://doi.org/10.17605/OSF.IO/GWAB7.

RESULTS

Heartbeat counting task performance did not change over blocks. In contrast, scores for the visual counting task reduced over time. A positive correlation was seen between performance in the two tasks (ρ(79) = .27).

CONCLUSION

Heartbeat counting task performance is stable across repetitions of the task, not changing with increasing familiarity. This suggests that non-interoceptive factors, such as beliefs, may be involved. The correlation between the heartbeat and visual counting tasks may point to a general propensity in counting uncertain stimuli across sensory domains. Together, these results raise questions about the interpretation of the heartbeat counting task as a measure of interoception.

Emotion dynamics and somatic symptoms in everyday life: Ecological momentary assessment in somatic symptom disorder and healthy controls

OBJECTIVE

Negative affectivity (NA) is associated with the emergence and persistence of physical symptoms with unclear organic pathology. This study investigated the temporal dynamics of NA and somatic symptom burden using ecological momentary assessment (EMA) in adults with somatic symptom disorder (SSD) and healthy control participants (HC).

METHODS

Participants underwent a seven-day, smartphone-based EMA, with 6 randomly-stratified time points per day. NA was assessed using a five-item short form of the Positive and Negative Affectivity Scale (PANAS) and somatic symptom burden with two self-constructed items. 22 persons with SSD and 20 HCs were included in multilevel analyses.

RESULTS

Within-person analyses showed a significantly stronger (positive) association of concurrent NA with somatic symptom burden in participants with SSD than in HCs, β = 0.15, SE = 0.04, p = .001. Time-lagged analyses demonstrated that, across groups, NA at a previous time point t-1 significantly predicted somatic symptom burden at the subsequent timepoint t, β = 0.09, SE = 0.03, p = .005, but not in the other direction (somatic symptom burdent-1→ NAt, β = 0.01, SE = 0.04, p = .79). Between-person analyses showed that both inertia (i.e., persistence of negative affective states), d = 0.74, and instability (i.e., magnitude of moment-to-moment fluctuations), d = 0.76 of NA were significantly higher in participants with SSD than in HCs.

CONCLUSIONS

Our findings sustain the idea of (negative) affect-driven modulation in somatic signal processing and suggest that interoceptive and emotional differentiation training can advance the psychotherapeutic treatment of SSD.

The emerging science of Glioception: Contribution of glia in sensing, transduction, circuit integration of interoception

Interoception is the process by which the nervous system regulates internal functions to achieve homeostasis. The role of neurons in interoception has received considerable recent attention, but glial cells also contribute. Glial cells can sense and transduce signals including osmotic, chemical, and mechanical status of extracellular milieu. Their ability to dynamically communicate "listening" and "talking" to neurons is necessary to monitor and regulate homeostasis and information integration in the nervous system. This review introduces the concept of "Glioception" and focuses on the process by which glial cells sense, interpret and integrate information about the inner state of the organism. Glial cells are ideally positioned to act as sensors and integrators of diverse interoceptive signals and can trigger regulatory responses via modulation of the activity of neuronal networks, both in physiological and pathological conditions. We believe that understanding and manipulating glioceptive processes and underlying molecular mechanisms provide a key path to develop new therapies for the prevention and alleviation of devastating interoceptive dysfunctions, among which pain is emphasized here with more focused details.

What is the role of interoception in the symptom experience of people with a chronic condition? A systematic review

BACKGROUND

Interoception, the ability of the organism to sense, interpret, and regulate signals originating from within the body, plays an important role in how individuals perceive and respond to symptoms. However, there is scarce evidence on the role of interoception in the symptom experience of people with chronic conditions.

AIM

To synthesize the role of interoception in the symptom experience of adults with a chronic condition.

METHODS

Systematic review. We searched PubMed, Psychinfo, Embase, CINAHL, and Science Citation Index-Expanded. We included primary research (all study designs) addressing our study aim, published between 2013-2021, and measuring at least one dimension of interoception. Any chronic condition and any symptom were included. No language limits were applied. Only the adult population was included.

RESULTS

We included 18 quantitative studies investigating the relationship between three interoceptive dimensions (i.e., accuracy, sensibility, awareness) and condition-specific symptoms in 10 chronic conditions. People with chronic conditions had lower interoceptive accuracy than healthy controls. Higher interoceptive sensibility was associated with lower symptom severity/frequency. Higher interoceptive accuracy was associated with lower symptom severity/frequency in half of the studies, while the other half reported the opposite. Only one study explored interoceptive awareness.

CONCLUSION

Interoceptive abilities are lower in patients with chronic conditions. Higher interoceptive sensibility is associated with lower symptom severity/frequency, but this relationship is unclear when it comes to interoceptive accuracy and awareness.

Prevalence of autistic traits in functional neurological disorder and relationship to alexithymia and psychiatric comorbidity

INTRODUCTION

In a cohort of adults with Functional Neurological Disorder (FND), we aim to: METHODS: 91 patients participating in a FND 5-week outpatient program completed baseline self-report questionnaires for total phobia, somatic symptom severity, attention deficit hyperactivity disorder (ADHD) and dyslexia. Patients were grouped by Autism Spectrum Quotient (AQ-10) score of <6 or ≥ 6 and compared for significant differences in tested variables. This analysis was repeated with patients grouped by alexithymia status. Simple effects were tested using pairwise comparisons. Multistep regression models tested direct relationships between autistic traits and psychiatric comorbidity scores, and mediation by alexithymia.

RESULTS

36 patients (40%) were AQ-10 positive (scoring ≥6 on AQ-10). A further 36 patients (across AQ-10 positive and AQ-10 negative groups) (40%) screened positive for alexithymia. AQ-10 positive patients scored significantly higher for alexithymia, depression, generalised anxiety, social phobia, ADHD, and dyslexia. Alexithymia positive patients scored significantly higher for generalised anxiety, depression, somatic symptoms severity, social phobia, and dyslexia. Alexithymia score was found to mediate the relationship between autistic trait and depression scores.

CONCLUSION

We demonstrate a high proportion of autistic and alexithymic traits, in adults with FND. A higher prevalence of autistic traits may highlight a need for specialised communication approaches in FND management. Mechanistic conclusions are limited. Future research could explore links with interoceptive data.

Interoception and Premonitory Urges in Children and Adolescents With Tic Disorders

Background

Compared to healthy controls (HCs), adult Tic Disorder (TD) patients exhibit a lower interoceptive accuracy (IAcc) in heartbeat perception. Since the lower IAcc is not evident in children, the age at which tics develop, but in adults only (Pile et al., 2018, https://doi.org/10.1007/s10803-018-3608-8), lower IAcc may reflect a pathological mechanism relevant with regard to tics, premonitory urges (PUs) or the resulting impairment. Although tics are a motor phenomenon, up to date, IAcc has been assessed only with a heartbeat-counting task. This study aims at comparing cardiac and muscular IAcc using two different paradigms and investigates how IAcc is related to premonitory urges in youth.

Method

Interoceptive measures (heartbeat-counting task, muscle tension paradigm) of 28 youth with TD were compared to 23 control participants and related to self-rated premonitory urges and tic symptoms.

Results

TD patients did not differ from HCs in any IAcc measures. However, within TD patients, IAcc explained additional variance in PUs when controlling for tic severity. Muscular IAcc in TD patients is related to urges and tics, but the direction of this association is unclear. IAcc is lower in TD patients than in HCs, indicating imprecise sensory input which is more easily overcome by priors within the predictive coding framework.

Conclusions

Muscle tension feedback tasks could extend interoceptive trainings aimed at improving IAcc to improve accuracy of urge perception (more precise sensory input) to foster the ability to control tics via HRT. Longitudinal studies could provide further insights in causal relationships between IAcc, premonitory urges and tics.

Temperature Perception in the Blushing Region

Abstract. Background: Individuals with social phobia are characterized by a heightened sensitivity for physical symptom such as blushing. Objectives: We exploratorily examined whether blushing-fearful individuals with / without social phobia were more sensitive to perceiving facial temperature increases compared to healthy controls. Methods: 50 participants were tested using an adaptive two-alternative forced-choice task. A Peltier element was attached to the cheek and repeatedly warmed up in one of two phases. The participants’ task was to indicate in which of the two phases the temperature had increased. Results: Contrary to our hypothesis, blushing-fearful individuals with social phobia ( n = 11) were less sensitive to facial temperature increases, i. e., exhibited higher temperature perception threshold, than the subclinical group ( n = 14) and healthy controls ( n = 23). Limitations: The preliminary nature of our study should be noted, and replication in a larger sample is warranted. Conclusions: The findings may be best understood within a predictive coding framework: Individuals with social phobia may rely on priors when assessing their physical symptoms to form an impression of their public self in social situations.

Die Bedeutung des Vorgefühls bei Tic-Störungen

Zusammenfassung. Theoretischer Hintergrund: Die Funktion des Vorgefühls in der Pathogenese und Aufrechterhaltung von Tic-Störungen (TS) wird in den letzten Jahren verstärkt erforscht. Die mögliche funktionelle Bedeutung der Vorgefühle wird aber noch nicht ausreichend verstanden. Methode: Im vorliegenden Review wird der Kenntnisstand zu Vorgefühlen entlang eines integrativen funktionalen Störungsmodells zusammengefasst. Ergebnisse: Im Vergleich zum Jugendalter nehmen Tic-Symptome bei Tic-Störungen im Erwachsenenalter ab, während immer mehr Betroffene ein Vorgefühl berichten. Hierbei kann zwischen einem allgemeinen Vorgefühl (trait) und dem Drang, Tics auszuführen (state) unterschieden werden. Das Vorgefühl als trait ist abhängig von der Interozeptionsfähigkeit. An den Drang, Tics auszuführen, kann habituiert werden, moderiert von Aufmerksamkeits- und Attributionsprozessen. Durch das Auflösen des Vorgefühl-Tic-Reizreaktionsmusters reduzieren sich die Tic-Symptome. Schlussfolgerung: Für weitere Erkenntnisse in Bezug auf die Bedeutung von Vorgefühl und den Drang, Tics auszuführen, sollten zukünftige Forschungsansätze Drang und allgemeine Vorgefühle in therapeutischen Interventionsstudien berücksichtigen, weitere Interozeptionsparadigmen einbeziehen und die Entwicklung von allgemeinem Vorgefühl und Drang über die Lebensspanne hinweg untersuchen.

Acute physical-activity related increases in interoceptive ability are not enhanced with simultaneous interoceptive attention

Interoception, the sense of the internal body, is proposed to support self-regulation, and consequently influence mental health. Researchers have therefore shown interest in improving the ability to accurately monitor internal signals (i.e., interoceptive accuracy, IAcc). Research suggests that cardiac IAcc is modifiable by both manipulations of interoceptive attention (guided attention towards the internal body), and interoceptive exposure (strategically inducing somatic signals e.g., via physical activity). Whilst successful in isolation, it is unclear whether a combined approach (i.e., directing attention towards the internal body when signals are more salient) could elicit greater benefits. In a 2 × 2 within-subject design, 48 healthy adults (M_age = 25.98 ± 4.73 years, 50% female) completed four 20-min conditions varying in both attentional focus (interoceptive vs exteroceptive) and physical activity (active vs rest), with cardiac IAcc measured immediately after. Results revealed a main effect for physical activity (p < 0.001), however, there was no effect for attentional focus (p = 0.397), and no interaction effect (p = 0.797). Differential analyses showed that a higher sporting background increased sensitivity to physical activity-related increases in cardiac IAcc (p = 0.031). Findings indicate that (irrespective of attentional focus) moderate-vigorous physical activity-based interventions have the potential to increase cardiac IAcc, with certain individuals potentially benefiting more.

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

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

Interoceptive accuracy is related to the psychological mechanisms of the burning mouth syndrome: a cross-sectional study

Background

Different perspectives are needed to understand the pathophysiology of burning mouth syndrome (BMS), including physiological and psychological standpoints. The significance of interoception in chronic pain has been suggested. However, few studies have investigated this relationship in BMS. Therefore, we examined the role of interoception in BMS.

Methods

This is a cross-sectional study. BMS patients (N = 64) participated in the study. We used interoceptive accuracy (IAc) based on the heartbeat counting task. Then, participants were divided into high and low IAc groups, and their scores on clinical assessment including pain and psychological evaluation were compared.

Results

The Visual Analogue Scale scores indicating pain in low IAc patients, but not high IAc patients, were positively correlated with the Beck Depression Inventory-Second Edition (BDI-II) and the State-Trait Anxiety Inventory-State (STAI-S) Scores.

Conclusions

Interoception might play a role in the pathophysiology of BMS.

Understanding Challenging Behaviors in Autism Spectrum Disorder: A Multi-Component, Interdisciplinary Model

A multi-component, interdisciplinary model is described which explains the presence of, and in other cases the lack of, many challenging behaviors associated with autism spectrum disorder (ASD). More specifically, the model expands the operant behavioral conditioning paradigm by taking into account medical comorbidities and interoceptive processing.

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.

Room to breathe: Using adaptive architecture to examine the relationship between alexithymia and interoception

OBJECTIVE

Individuals with alexithymia experience difficulties interpreting emotional states in self and others, which has been associated with interoceptive impairment. Current theories are primarily based on subjective and conscious measures of interoceptive sensitivity, such as heartrate detection, but it is unclear whether similar observations would be found for objective or implicit psychophysiological measures. The present exploratory study assesses the potential of a novel assay through the use of adaptive immersive architecture [ExoBuilding].

METHODS

N = 88 participants were screened for alexithymic traits and N = 27 individuals, representing the range of scores, were sampled to participate in the behavioural task. In a repeated-measures design, participants were placed within ExoBuilding and asked to match their respiration to its movement. Performance was compared to a two-dimensional pacer condition. Behavioural (accuracy) and psychophysiological (Respiratory Sinus Arrhythmia [RSA] and heartrate) measures were compared across conditions, and also related to individual alexithymic traits.

RESULTS

Participants with higher levels of alexithymia performed less accurately than participants with lower levels, in both conditions. High-alexithymia participants showed a smaller reduction in heartrate over the course of the ExoBuilding condition than low-alexithymia participants, although there were no differences in RSA between conditions or participants.

CONCLUSION

Alexithymia extends beyond conscious interoceptive activities and is also observed in immersive contexts that usually exert psychophysiological effects on typical occupants. These initial findings highlight the importance of considering both conscious and implicit measures of interoception, and we suggest ways in which theories of alexithymia might benefit from capturing this distinction.

Psychobiological Mechanisms in Somatic Symptom Disorder and Depressive Disorders: An Ecological Momentary Assessment Approach

OBJECTIVE

Persistent somatic symptoms cause strong impairment in persons with somatic symptom disorder (SSD) and depressive disorders (DDs). Specific negative psychological factors (NPFs), such as catastrophizing, negative affectivity, and behavioral avoidance, are assumed to contribute to this impairment and may maintain symptoms via dysregulations of biological stress systems. We examined the associations between NPF and somatic symptoms in the daily life of women with SSD or DD and investigated the mediating role of psychobiological stress responses.

METHODS

Twenty-nine women with SSD and 29 women with DD participated in an ecological momentary assessment study. For 14 days, intensity of and impairment by somatic symptoms, NPF, and stress-related biological measures (cortisol, alpha-amylase) were assessed five times per day using an electronic device and saliva samples. Multilevel models were conducted.

RESULTS

The greater the number of NPF, the higher the concurrent and time-lagged intensity of and impairment by somatic symptoms in both groups (12.0%-38.6% of variance explained; χ2(12) p < .001 for all models). NPFs were associated with higher cortisol levels in women with DD and with lower levels in women with SSD (interaction NPF by group: B = -0.04, p = .042 for concurrent; B = -0.06, p = .019 for time-lagged). In women with SSD, lower cortisol levels were associated with higher intensity at the next measurement time point (group by cortisol: B = -1.71, p = .020). No mediation effects were found.

CONCLUSIONS

NPFs may be considered as transdiagnostic factors in the development and treatment of impairing somatic symptoms. Our findings will allow the development of new treatment strategies that use ecological momentary intervention approaches focusing on NPF.

Interoception and social cognition in chronic low back pain: a common inference disturbance? An exploratory study

Aim: Lower interoceptive abilities are a characteristic of chronic pain conditions. Social support plays an important role in chronic low back pain (cLBP) but social cognitive skills have rarely been investigated. This study aimed to characterize interoceptive and social cognitive abilities in cLBP and to study the relationship between both domains that have been brought closer together by brain predictive coding models. Materials & methods: Twenty-eight patients with cLBP and 74 matched controls were included. Interoceptive accuracy (Heart Beat Perception Task), sensibility/awareness (Multidimensional Assessment of Interoceptive Awareness) and mental-states inference abilities (Mini-Social Cognition and Emotional Assessment) were assessed. Results: cLBP Patients had lower interoceptive accuracy and mentalizing performance. Conclusion: Less efficient interoceptive accuracy and mentalizing abilities were found in cLBP patients without correlation between these performances.

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.

Interoception abnormalities in schizophrenia: A review of preliminary evidence and an integration with Bayesian accounts of psychosis

Schizophrenia research has traditionally focused almost exclusively on how the brain interprets the outside world. However, our internal bodily milieu is also central to how we interpret the world and construct our reality: signals from within the body are critical for not only basic survival, but also a wide range of brain functions from basic perception, emotion, and motivation, to sense of self. In this article, we propose that interoception-the processing of bodily signals-may have implications for a wide range of clinical symptoms in schizophrenia and may thus provide key insights into illness mechanisms. We start with an overview of interoception pathways. Then we provide a review of direct and indirect findings in various interoceptive systems in schizophrenia and interpret these findings in the context of computational frameworks that model interoception as hierarchical Bayesian inference. Finally, we propose a conceptual model of how altered interoceptive inference may contribute to specific schizophrenia symptoms-negative symptoms in particular-and suggest directions for future research, including potential new avenues of treatment.

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.

The effect of aerobic exercise on interoception and cognitive function in healthy university students: a non-randomized controlled trial

BACKGROUND

Interoception refers to the body's physiological responses that occur in response to emotions. This phenomenon influences decision-making, an important cognitive ability that affects the maintenance of an exercise routine. However, it is controversial whether interoception is a reliable measure of an individual's traits or their response to emotion. Given this evidence, we hypothesized that performing an exercise with positive feelings could improve interoception and that the rational decision-making capabilities acquired by improved interoception would, in turn, help in maintaining an exercise routine. Persistent aerobic exercise is essential for improving cognitive and musculoskeletal function in the long term. Therefore, we aimed to investigate changes in interoception during moderate-intensity aerobic exercise at a level that might potentially improve cognitive function.

METHODS

We devided 48 healthy university students into an exercise group (n = 37) and a control group (n = 11). The control group did not perform any exercises, while the exercise group performed bench step exercises at an intensity of 50% of heart rate reserve for 30 min a day, three times a week, for three months. We assessed their cognitive function by measuring their auditory information/working memory processing speed using a paced auditory serial addition task (PASAT) and evaluated their interoceptive accuracy (IA) using a heartbeat tracking task at baseline and 1, 2, and 3 months after the start of the exercise intervention.

RESULTS

There was a significant positive correlation between IA and PASAT scores at baseline. However, exercise did not lead to a significant increase in PASAT scores of the exercise group as compared with the control group. IA scores increased at 2 and 3 months after the start of exercise only in the exercise group.

CONCLUSIONS

This preliminary study showed an improvement in interoception after persistent moderate-intensity aerobic exercise. We believe that exercise-induced improvement of interoception may facilitate exercise maintenance through improved cognitive function. Statistical analysis did not explain the non-uniformity of sample sizes, therefore, future studies should have larger sample sizes with equal subjects in each group to allow for better comparability and generalizability.

TRIAL REGISTRATION

UMIN, UMIN000042891. 04/01/2021, retrospectively registered.

Widespread Pressure Delivered by a Weighted Blanket Reduces Chronic Pain: A Randomized Controlled Trial

Pleasant sensation is an underexplored avenue for modulation of chronic pain. Deeper pressure is perceived as pleasant and calming, and can improve sleep. Although pressure can reduce acute pain, its effect on chronic pain is poorly characterized. The current remote, double-blind, randomized controlled trial tested the hypothesis that wearing a heavy weighted blanket - providing widespread pressure to the body - relative to a light weighted blanket would reduce ratings of chronic pain, mediated by improvements in anxiety and sleep. Ninety-four adults with chronic pain were randomized to wear a 15-lb. (heavy) or 5-lb. (light) weighted blanket during a brief trial and overnight for one week. Measures of anxiety and chronic pain were collected pre- and post-intervention, and ratings of pain intensity, anxiety, and sleep were collected daily. After controlling for expectations and trait anxiety, the heavy weighted blanket produced significantly greater reductions in broad perceptions of chronic pain than the light weighted blanket (Cohen's f = .19, CI [-1.97, -.91]). This effect was stronger in individuals with high trait anxiety (P = .02). However, weighted blankets did not alter pain intensity ratings. Pain reductions were not mediated by anxiety or sleep. Given that the heavy weighted blanket was associated with greater modulation of affective versus sensory aspects of chronic pain, we propose that the observed reductions are due to interoceptive and social/affective effects of deeper pressure. Overall, we demonstrate that widespread pressure from a weighted blanket can reduce the severity of chronic pain, offering an accessible, home-based tool for chronic pain. The study purpose, targeted condition, study design, and primary and secondary outcomes were pre-registered in ClinicalTrials.gov (NCT04447885: "Weighted Blankets and Chronic Pain"). Perspective: This randomized-controlled trial showed that a 15-lb weighted blanket produced significantly greater reductions in broad perceptions of chronic pain relative to a 5-lb weighted blanket, particularly in highly anxious individuals. These findings are relevant to patients and providers seeking home-based, nondrug therapies for chronic pain relief.

Interoception, eating behaviour and body weight

BACKGROUND

Interoception refers to the process of identifying and listening to internal bodily signals, which may be a modifiable determinant of appetite regulation and weight gain. The objective was to examine whether the extent to which self-reported interoception is associated with higher BMI is explained by eating behavior traits.

METHODS

UK adults (N = 1181, 49% female, 53% with overweight/obesity) completed validated self-report measures of interoception, habitual tendencies to eat in response to satiety signals (intuitive eating), emotional over-eating and other eating traits.

RESULTS

Poorer self-reported ability to detect interoceptive signals (deficits in interoceptive accuracy) was predictive of higher BMI (r = - 0.07 (95% CI -0.13; -0.01), p < .05). In parallel mediation analyses, participants with poorer interoceptive accuracy were significantly less likely to report considering satiety signals when eating and this explained the cross-sectional association between interoceptive accuracy and higher BMI. There was also some evidence that participants with poorer interoceptive accuracy were more likely to report emotional overeating and this also in part explained why interoceptive accuracy was predictive of higher BMI.

CONCLUSIONS

Deficits in interoception may decrease the likelihood that satiety signals are integrated into eating behaviour related decision making and in doing so contribute to higher BMI.

Noradrenergic activation induced by yohimbine decreases interoceptive accuracy in healthy individuals with childhood adversity

Acute stress affects interoception, but it remains unclear if this is due to activation of the sympatho-adreno-medullary (SAM) or hypothalamic-pituitary-adrenocortical axis. This study aimed to investigate the effect of SAM axis activation on interoceptive accuracy (IAcc). Central alpha2-adrenergic receptors represent a negative feedback mechanism of the SAM axis. Major depressive disorder and adverse childhood experiences (ACE) are associated with alterations in the biological stress systems, including central alpha2-adrenergic receptors. Here, healthy individuals with and without ACE as well as depressive patients with and without ACE (n = 114; all without antidepressant medication) were tested after yohimbine (alpha2-adrenergic antagonist) and placebo. We assessed IAcc and sensibility in a heartbeat counting task. Increases in systolic and diastolic blood pressure after yohimbine confirmed successful SAM axis activation. IAcc decreased after yohimbine only in the healthy group with ACE, but remained unchanged in all other groups (Group × Drug interaction). This effect may be due to selective upregulation of alpha2-adrenergic receptors after childhood trauma, which reduces capacity for attention focus on heartbeats. The sympathetic neural pathway including alpha2-adrenergic circuitries may be essential for mediating interoceptive signal transmission. Suppressed processing of physical sensations in stressful situations may represent an adaptive response in healthy individuals who experienced ACE.

Psychogenic non-epileptic seizures in children - psychophysiology & dissociative characteristics

The purpose of this study was to determine psychophysiology and dissociative characteristics of psychogenic non-epileptic seizures (PNES) in a clinical pediatric setting. A retrospective chart review was conducted over a 5-year period that included children meeting criteria for probable, clinically established or documented PNES. Of these, 33 patients (81%) underwent psychophysiology assessment as part of standardized care and were selected for study inclusion. Ages ranged from 10 to 17 years inclusive (70% female). The majority of patients were found to have some form of autonomic decompensation at baseline (82%) and lack of autonomic recovery from a cognitive stressor (58%). Inhibition of electrodermal skin response to laboratory stressor was associated with significantly longer duration of PNES illness (t=2.65, p=.013), while elevated heart rate (above 90^th percentile) was associated with significantly higher frequency of PNES events in the month preceding diagnosis (t=3.1, p=.004). High levels of dissociation and hyperventilation symptoms were self-reported by adolescent patients (n=19) with a moderate degree of positive association (r=0.35, p=.038). The majority of patients (n= 25, 89%) were taught to correct respiratory CO₂ levels during a single biofeedback training session. Conclusions: Child PNES populations appear to be characterized by chronic autonomic hyperarousal reflecting severity of their symptoms, which can feasibly be targeted for behavioral treatment.

Better Safe Than Sorry: A Common Signature of General Vulnerability for Psychopathology

Several labels, such as neuroticism, negative emotionality, and dispositional negativity, indicate a broad dimension of psychopathology. However, largely separate, often disorder-specific research lines have developed that focus on different cognitive and affective characteristics that are associated with this dimension, such as perseverative cognition (worry, rumination), reduced autobiographical memory specificity, compromised fear learning, and enhanced somatic-symptom reporting. In this article, we present a theoretical perspective within a predictive-processing framework in which we trace these phenotypically different characteristics back to a common underlying “better-safe-than-sorry” processing strategy. This implies information processing that tends to be low in sensory-perceptual detail, which allows threat-related categorical priors to dominate conscious experience and for chronic uncertainty/surprise because of a stagnated error-reduction process. This common information-processing strategy has beneficial effects in the short term but important costs in the long term. From this perspective, we suggest that the phenomenally distinct cognitive and affective psychopathological characteristics mentioned above represent the same basic processing heuristic of the brain and are only different in relation to the particular type of information involved (e.g., in working memory, in autobiographical memory, in the external and internal world). Clinical implications of this view are discussed.

Interoception, Stress, and Physical Symptoms in Stress-Associated Diseases

Abstract. The brain and peripheral bodily organs continuously exchange information. Exemplary, interoception refers to the processing and perception of ascending information from the body to the brain. Stress responses involve a neurobehavioral cascade, which includes the activation of peripheral organs via neural and endocrine pathways and can thus be seen as an example for descending information on the brain-body axis. Hence, the interaction of interoception and stress represents bi-directional communication on the brain-body axis. The main hypothesis underlying this review is that the dysregulation of brain-body communication represents an important mechanism for the generation of physical symptoms in stress-related disorders. The aims of this review are, therefore, (1) to summarize current knowledge on acute stress effects on different stages of interoceptive signal processing, (2) to discuss possible patterns of abnormal brain-body communication (i.e., alterations in interoception and physiological stress axes activation) in mental disorders and chronic physical conditions, and (3) to consider possible approaches to modify interoception. Due to the regulatory feedback loops underlying brain-body communication, the modification of interoceptive processes (ascending signals) may, in turn, affect physiological stress axes activity (descending signals), and, ultimately, also physical symptoms.

Distinctive body perception mechanisms in high versus low symptom reporters: A neurophysiological model for medically-unexplained symptoms

OBJECTIVE

The neurophysiological processes involved in the generation of medically-unexplained symptoms (MUS) remain unclear. This study tested three assumptions of the perception-filter model contributing to MUS: (I.) increased bodily signal strength (II.) decreased filter function, (III.) increased perception.

METHODS

In this cross-sectional, observational study, trait MUS were assessed by a web-based survey (N = 486). The upper and lower decile were identified as extreme groups of high (HSR; n = 29; 26 women; Mage = 26.0 years) and low symptom reporters (LSR; n = 29; 21 women; Mage = 28.4 years). Mean heart rate (HR) and heart rate variability (HRV), and cortisol awakening response (CAR) were assessed as indicators of bodily signal strength (I.). Heartbeat-evoked potentials (HEPs) were assessed during rest and a heartbeat perception task. HEPs reflect attentional resources allocated towards heartbeats and served as index of filter function (II.). Interoceptive accuracy (IAc) in heartbeat perception was assessed as an indicator of perception (III.).

RESULTS

HSR showed higher HR and lower HRV (RMSSD) than LSR (I.), but no differences in CAR. HSR exhibited a stronger increase of HEPs when attention was focused on heartbeats than LSR (II.); there were no group differences in IAc (III.).

CONCLUSIONS

The perception-filter model was partially confirmed in that HSR showed altered bodily signals suggesting higher sympathetic activity (I.); higher HEP increases indicated increased filter function for bodily signals (II.). As more attentional resources are mobilized to process heartbeats, but perception accuracy remains unchanged (III.), this overflow could be responsible for detecting minor bodily changes associated with MUS.

Behavioral and neurophysiological evidence for altered interoceptive bodily processing in chronic pain

Whereas impaired multisensory processing of bodily stimuli and distorted body representation are well-established in various chronic pain disorders, such research has focused on exteroceptive bodily cues and neglected bodily signals from the inside of the body (or interoceptive signals). Extending existing basic and clinical research, we investigated for the first time interoception and its neurophysiological correlates in patients with complex regional pain syndrome (CRPS). In three different experiments, including a total of 36 patients with CRPS and 42 aged-gender matched healthy controls, we measured interoceptive sensitivity (heart beat counting task, HBC) and neural responses to heartbeats (heartbeat evoked potentials, HEPs). As hypothesized, we observed reduced sensitivity in perceiving interoceptive bodily stimuli, i.e. their heartbeat, in two independent samples of CRPS patients (studies 1 and 2). Moreover, the cortical processing of their heartbeat, i.e. the HEP, was reduced compared to controls (study 3) and reduced interoceptive sensitivity and HEPs were related to CRPS patients' motor impairment and pain duration. By providing consistent evidence for impaired processing of interoceptive bodily cues in CRPS, this study shows that the perceptual changes occurring in chronic pain include signals originating from the visceral organs, suggesting changes in the neural body representation, that includes next to exteroceptive, also interoceptive bodily signals. By showing that impaired interoceptive processing is associated with clinical symptoms, our findings also encourage the use of interoceptive-related information in future rehabilitation for chronic pain.

Somatic Symptom Perception and Interoception

Abstract. Models of chronic somatic symptoms assume that abnormalities in interoception are related to the development and maintenance of symptom distress. Different models, however, disagree on the exact nature of the assumed abnormality: cognitive-behavioral models stress a hypervigilant cognitive style (predicting higher interoceptive accuracy) whereas predictive processing models assume a less detailed sensory processing (predicting lower interoceptive accuracy). This study aimed at testing the relationship between interoception and symptom perception. Using structural equation modeling, associations between cardiac interoception and symptom perception were tested in a sample of students ( n = 316) and a second heterogeneous sample ( n = 340, including 63 patients with either pathological health anxiety or a somatoform disorder according to DSM-IV). Stronger sensory symptom perceptions in the cardiorespiratory system were associated with lower interoceptive accuracy in sample 2. The findings are more in line with the predictive processing approach, suggesting less detailed and more biased interoception being associated with chronic somatic symptom distress.

Mutual-Aid Mobile App for Emergency Care: Feasibility Study

BACKGROUND

Improving the quality of patient care through the use of mobile devices is one of the hot topics in the health care field. In unwanted situations like an accident, ambulances and rescuers often require a certain amount of time to arrive at the scene. Providing immediate cardiopulmonary resuscitation (CPR) to patients might improve survival.

OBJECTIVE

The primary objective of this study was to evaluate the feasibility of an emergency and mutual-aid app model in Taiwan and to provide a reference for government policy.

METHODS

A structured questionnaire was developed as a research tool. All questionnaires were designed according to the technology acceptance model, and a Likert scale was used to measure the degree of agreement or disagreement. Moreover, in-depth interviews were conducted with six experts from medical, legal, and mobile app departments. Each expert was interviewed once to discuss feasible countermeasures and suggestions. Statistical Package for the Social Sciences (SPSS version 19; IBM Corp, Armonk, New York) was used to perform all statistical analyses, including descriptive statistics, independent sample t-tests, variance analysis, and Pearson correlation analysis.

RESULTS

We conducted this study between October 20, 2017, and November 10, 2017, at the Taipei Medical University Hospital. Questionnaires were distributed to medical personnel, visiting guests, family members, and volunteers. A total of 113 valid questionnaires were finally obtained after the exclusion of incomplete questionnaires. Cronbach α values for self-efficacy (perceived ease of use), use attitude (perceived usefulness), and use willingness and frequency were above .85, meeting the criterion of greater than .70. We observed that the reliability of each subquestion was acceptable and the values for use attitude (perceive usefulness) and use willingness and frequency were more than .90.

CONCLUSIONS

The findings suggest that perceived ease of use and perceived usefulness of the app model affect use willingness. However, perceived usefulness had an intermediary influence on use willingness. Experts in law, medical, and technology fields consider that an emergency and mutual-aid model can be implemented in Taiwan. Along with the development of an emergency and mutual-aid app model, we recommend an increase in the number of automated external defibrillators per region and promotion of correct knowledge about CPR in order to decrease morbidity and mortality.

Multisensory mechanisms of body perception in somatoform disorders

OBJECTIVE

According to one of the hypotheses, somatoform disorders (SD) are related to disturbed perception of bodily signals. We suspect that the disturbances and abnormalities of multisensory integration dynamics may be an additional SD mechanism. The objective of the research was to investigate multisensory bodily illusion dynamics in SD patients.

METHODS

A clinical group of SD patients (n = 16) and a control group (n = 17) participated in experiments aimed at eliciting a visual-tactile rubber hand illusion (RHI) and a visual-kinesthetic virtual hand illusion (VHI).

RESULTS

For both illusions studied, the illusion dynamics in SD patients differed from those of healthy subjects. The visual-tactile illusion on the subjective level appeared to be less strong in SD patients, and no proprioceptive drift (PD) was detected. The subjective dynamics of the visual-kinesthetic illusion in patients were similar to those of the control group, but the PD dynamics were different: after the termination of stimuli from the artificial limb, the proprioceptive system did not return to its initial state; on the contrary, PD continued to increase.

CONCLUSION

In comparison with the norm, patients with somatoform disorders display differences in multisensory mechanisms underlying the development of body perception. The results suggest that the disturbance of visual-tactile integration of the stimuli represents one of the mechanisms of body perception distortion in somatoform disorders. It may be assumed that one of the reasons for persistent symptom perception in SD patients is the rigidity of multisensory stimuli perception, at least in the visual-motor domain.

The relationship between mindfulness and objective measures of body awareness: A meta-analysis

Although awareness of bodily sensations is a common mindfulness meditation technique, studies assessing the relationship between mindfulness and body awareness have provided mixed results. The current study sought to meta-analytically examine the relationship between mindfulness operationalized as a dispositional trait or a construct trained through short- (i.e., randomized controlled trials [RCTs]) or long-term mindfulness meditation practice with objective measures of body awareness accuracy. PubMed, Web of Science, PsycINFO, and Scopus were searched. Studies were eligible if they reported the association between mindfulness and body awareness, were published in English, and included adults. Across 15 studies (17 independent samples), a small effect was found linking mindfulness with greater body awareness accuracy (g = 0.21 [0.08, 0.34], N = 879). When separated by study design, only RCTs continued to show a significant relationship (g = 0.20, [0.02, 0.38], k = 7, n = 505). Heterogeneity of effects was low (I² < 25%), although with wide confidence intervals. Effects were not moderated by study quality. Low fail-safe N estimates reduce confidence in the observed effects. Results suggest a small but potentially detectable relationship between mindfulness and body awareness accuracy. Future investigations could examine individual differences in body awareness as a mechanism within mindfulness interventions.