Interoceptive sensitivity modulates heart rate and insula activity when listening to music

Interoception plays an important role in emotion processing, but the relationship between the physiological responses associated with emotional experience and interoception is unclear. In this study, we measured interoceptive sensitivity using the heartbeat discrimination task and investigated the effects of individual differences in interoceptive sensitivity on changes in heart rate and insula activity in response to music-induced emotions. We found that the heart rate increased when listening to the music pieces rated as emotionally high-touching in the high interoceptive sensitivity group only. Compared to the emotionally low-touching music, listening to the emotionally high-touching music was associated with higher insula activity. Furthermore, relative to individuals with low interoceptive sensitivity, the region of interest analysis of the insula subregions for individuals with high interoceptive sensitivity revealed significant activity in the bilateral dorsal granular insula, the right ventral dysgranular insula, and the right granular and dorsal dysgranular insula while listening to the high-touching music pieces. Our results suggest that individuals with high interoceptive sensitivity use their physical condition to assess their emotional level when listening to music. Furthermore, the insula activity may reflect the use of interoception to estimate emotions.

Sensitivity to changes in rate of heartbeats as a measure of interoceptive ability

Individuals vary in their ability to perceive, as conscious sensations, signals like the beating of the heart. Tests of such interoceptive ability are, however, constrained in nature and reliability. Performance of the heartbeat tracking task, a widely used test of cardiac interoception, often corresponds well with individual differences in emotion and cognition, yet is susceptible to reporting bias and influenced by higher order knowledge, e.g. of expected heart rate. The present study introduces a new way of assessing cardiac interoceptive ability, focusing on sensitivity to short-term, naturalistic changes in frequency of heartbeats. At rest, such heart rate variability typically reflects the dominant influence of respiration on vagus parasympathetic control of the sinoatrial pacemaker. We observed an overall tendency of healthy participants to report feeling fewer heartbeats during increases in heart rate, which we speculate reflects a reduction in heartbeat strength and salience during inspiratory periods when heart rate typically increases to maintain a stable cardiac output. Within-participant performance was more variable on this measure of cardiac interoceptive sensitivity relative to the 'classic' heartbeat tracking task. Our findings indicate that cardiac interoceptive ability, rather than reflecting the veridical monitoring of subtle variations in physiology, appears to involve more interpolation wherein interoceptive decisions are informed by dynamic working estimates derived from the integration of afferent signalling and higher order predictions.

The Respiratory Resistance Sensitivity Task: An Automated Method for Quantifying Respiratory Interoception and Metacognition

The ability to sense, monitor, and control respiration - e.g., respiratory interoception (henceforth, respiroception) is a core homeostatic ability. Beyond the mere regulation of gas exchange, enhanced awareness of respiratory sensations is directly related to psychiatric symptoms such as panic and anxiety. Indeed, chronic breathlessness (dyspnea) is associated with a fourfold increase in the risk of developing depression and anxiety, and the regulation of the breath is a key aspect of many mindfulness-based approaches to the treatment of mental illness. Physiologically speaking, the ability to accurately monitor respiratory sensations is important for optimizing cardiorespiratory function during athletic exertion, and can be a key indicator of illness. Given the important role of respiroception in mental and physical health, it is unsurprising that there is increased interest in the quantification of respiratory psychophysiology across different perceptual and metacognitive levels of the psychological hierarchy. Compared to other more popular modalities of interoception, such as in the cardiac domain, there are relatively few methods available for measuring aspects of respiroception. Existing inspiratory loading tasks are difficult to administer and frequently require expensive medical equipment, or offer poor granularity in their quantification of respiratory-related perceptual ability. To facilitate the study of respiroception, we here present a new, fully automated and computer-controlled apparatus and psychophysiological method, which can flexibly and easily measure respiratory-related interoceptive sensitivity, bias and metacognition, in as little as 30 minutes of testing, using easy to make 3D printable parts.

Electrodermal Response to Mirror Exposure in Relation to Subjective Emotional Responses, Emotional Competences and Affectivity in Adolescent Girls With Restrictive Anorexia and Healthy Controls

Objective: Body image disturbances and the attendant negative emotions are two of the major clinical symptoms of eating disorders. The objective of the present experimental study was to shed more light on the degree of association or dissociation between the physiological and emotional response to mirror exposure in patients with restrictive mental anorexia, and on the relationships between the physiological response and characteristics connected with emotional processing.Materials and Methods: Thirty adolescent girls with the restrictive type of anorexia and thirty matched healthy controls underwent bilateral measurement of skin conductance (SC) during rest, neutral stimulus exposure, and mirror exposure, and completed a set of measures focused on emotion regulation competencies, affectivity, and eating disorder pathology.Results: Compared to healthy controls, girls with restrictive anorexia rated mirror exposure as a subjectively more distressful experience. Differences in skin conductance response (SCR) were not significant; however, variance in SCR was substantially greater in the group of anorexia patients as compared to healthy controls. The overall skin conductance level (SCL) was lower in anorexia patients. Increase in SCR during mirror exposure, as opposed to exposure to neutral stimuli, was positively related to the tendency to experience negative emotions, interoceptive sensitivity, body dissatisfaction and suppression, but not to other symptoms of eating pathology or emotional awareness. A post hoc analysis suggested that physiological reactivity might be associated with interoceptive sensitivity to mirror exposure especially in anorectic patients.Conclusion: The study seems to demonstrate some degree of dissociation between psychophysiological reactivity and subjective response to body exposure in patients with restrictive anorexia. Factors affecting differences in psychophysiological responsiveness to body exposure in anorectic patients require further exploration.

Heartbeat-Evoked Cortical Potential during Sleep and Interoceptive Sensitivity: A Matter of Hypnotizability

Individuals with different hypnotizability display different interoceptive sensitivity/awareness (IS) and accuracy (IA), likely sustained by morphofunctional differences in interoception-related brain regions and, thus, possibly also observable during sleep. We investigated the heartbeat-evoked cortical potential amplitude (HEP) during sleep, its association with IS, and the role of hypnotizability in such association. We performed a retrospective analysis of polysomnographic recordings of 39 healthy volunteers. Participants completed the Multidimensional Assessment of Interoceptive Awareness (MAIA), measuring IS and IA, and underwent hypnotic assessment via the Stanford Hypnotic Susceptibility Scale, form A. The amplitude of the early and late HEP components was computed at EEG frontal and central sites. In both regions, the early HEP component was larger in N3 than in N2 and REM, with no difference between N2 and REM. Greater HEP amplitude at frontal than at central sites was found for the late HEP component. HEP amplitudes were not influenced by the autonomic state assessed by heart rate variability in the frequency and time domains. We report for the first time a positive correlation between the central late HEP component and MAIA dimensions, which became non-significant after removing the effects of hypnotizability. Our findings indicate that hypnotizability sustains the correlation between IS and HEP amplitude during sleep.

The Relationship between Interoceptive Sensitivity, Age, and COVID-19 Anxiety During the First National Lockdown in the United Kingdom

Interoception refers to the multidimensional representation of the internal states of the body, including their sensation, appraisal, integration, and regulation. COVID-19 targets internal respiratory, temperature and gastrointestinal systems, thus posing a primary threat to humans that causes anxiety. Here, we examined the relationship between the sensitivity to internal bodily states and COVID-19 anxiety during the first national lockdown in the UK, when uncertainties surrounding the virus were at their peak. Between April and July 2020, N=232 individuals across 6 age-categories completed questionnaires measuring interoceptive sensibility (BPQ-SF and MAIA-2) and COVID-19 anxiety (adapted STAI). Several significant relationships suggested that the heightened sensation and the noticing of bodily signals were associated with higher COVID-19 anxiety, while healthy appraisal, attention regulation, mind-body integration and trusting of bodily signals were related to lower levels of COVID-19 anxiety. Age was associated with changes across multiple interoceptive dimensions and was related to lower levels of COVID-19 anxiety. Regression results further revealed that, after controlling for trait anxiety, higher age significantly predicted lower levels of COVID-19 anxiety, and a lower score on the Not Worrying subscale significantly predicted higher levels of COVID-19 anxiety. Our results extend previous findings of an age-related decline in COVID-19 anxiety to suggest underlying biopsychological changes in interoception. Interoceptive sensitivity may significantly influence anxiety management and regulate adaptive behaviour in the presence of health threats. Age-related interoceptive changes therefore raise important questions about best-practice guidance for individuals across the lifespan in protecting their own and other’s physical and mental health during a pandemic.

Changes in interoception after alcohol administration correlate with expectancies and subjective effects

Interoceptive signals give rise to subjective feeling states that can drive motivational and behavioral responses. In the context of alcohol use behaviors, interoceptive signals may shape subjective alcohol experiences, and thereby support bio-behavioral mechanisms of drinking behavior change. This study examined the acute effects of alcohol on participants’ interoceptive sensitivity, and determined whether pharmacologically induced changes in heart beat detection correlate with subjective alcohol effects, craving and expectancies.Participants completed a two-session, double-blind placebo controlled experiment (n=31). Participants consumed a beverage containing 0.4g/kg of alcohol or a placebo. They also completed measurements of alcohol expectancies at baseline, and alcohol-induced changes in mood, craving and light-headedness. Interoceptive sensitivity was measured using the heartbeat discrimination task prior to and following beverage administration, yielding indices of interoceptive accuracy, confidence and meta-cognition. Alcohol administration increased interoceptive accuracy compared to baseline and placebo; and those changes in interoception negatively correlated with negative alcohol expectancies. Further, changes in interoception positively correlated with perceived light-headedness and positive mood after alcohol administration, whereas null effects were found for craving. In the placebo condition, null results were obtained. Alcohol is well established to change bodily states, and here we find that the extent to which alcohol increases participants’ sensitivity to bodily states impacts their subjective drinking experiences. This was observed in relation to mood and light-headedness, but also on prospective alcohol expectancies. We posit that over successive alcohol experiences, changes in bodily states may feed into the development of alcohol expectancies that could in turn predict future drinking behaviors.

The Filter Detection Task for measurement of breathing-related interoception and metacognition

The study of the brain’s processing of sensory inputs from within the body (‘interoception’) has been gaining rapid popularity in neuroscience, where interoceptive disturbances have been postulated to exist across a wide range of chronic physiological and psychological conditions. Here we present a task and analysis procedure to quantify specific dimensions of breathing-related interoception, including interoceptive sensitivity (accuracy), decision bias, metacognitive bias, and metacognitive performance. We describe a task that is tailored to methods for assessing respiratory interoceptive accuracy and metacognition, and pair this with an established hierarchical statistical model of metacognition (HMeta-d) to overcome significant challenges associated with the low trial numbers often present in interoceptive experiments. Two major new developments have been incorporated into this task analysis by pairing: (i) a novel adaptive algorithm to maintain task performance at 70-75% accuracy, and (ii) an extended metacognitive model developed to hierarchically estimate multiple regression parameters linking metacognitive performance to relevant (e.g. clinical) variables. We demonstrate the utility of both developments, using both simulated and empirical data from three separate studies. This methodology represents an important step towards accurately quantifying interoceptive dimensions from a simple experimental procedure that is compatible with the practical constraints in clinical settings. Both the task and analysis code are publicly available.