Cardiac and Proprioceptive Accuracy Are Not Related to Body Awareness, Perceived Body Competence, and Affect

I can feel my heartbeat: The relationship between interoceptive abilities and emotional states during stress and recovery in healthy adolescents

The goal of the current study was to investigate the differential effects of three interoception dimensions on psychophysiological stress responses (reactivity and recovery) in adolescents. A total of 102 adolescents (Mage = 14.10 years, SDage = 0.63; 50 males) completed the heartbeat counting task with adapted instructions to assess interoceptive accuracy, sensibility, and awareness. During a follow-up session, participants underwent a standardized stressful task, throughout which measures of negative affect and respiratory sinus arrythmia (RSA) were collected. Results from multilevel models indicated that adolescents with higher interoceptive accuracy reported less pronounced increases in negative affect during stress induction, and subsequently experienced a less steep decrease in negative affect during recovery, compared to those with lower accuracy. Regarding RSA, adolescents with higher interoceptive accuracy exhibited greater decreases in RSA from baseline to stress, while those with higher interoceptive awareness maintained higher RSA levels throughout the experiment. In contrast, individuals with higher interoceptive sensibility exhibited lower levels of RSA during the experiment. These findings add to the limited literature on interoception in adolescents by illuminating its role in emotional experiences, stress responses, and recovery processes. Our study suggests that examining distinct dimensions of interoception, along with physiological measures during stress and recovery, is crucial for understanding its beneficial or adverse effects in adolescence. The complexity and potential significance of interoceptive dimensions extend beyond their correlations with traditional self-report measures, warranting further investigation to clarify their implications and underlying mechanisms.

Slow stroking evokes a more pleasant sensation but similar autonomic nervous system response than rhythmic touching

Stimulation of C-tactile afferents with gentle slow stroking of the hairy skin, also called affective touch, evokes a pleasant sensation. We intended to describe psychological and tonic physiological changes evoked by slow stroking, as well as associations between pleasantness of skin sensation and physiological changes and trait-like self-reported characteristics (i.e., the major dimensions of personality and various aspects of body awareness). To shed more light on the factors involved in the effects of slow stroking, stroking (5 cm/sec) for 3 minutes was compared to skin-focused attention and gentle rhythmic touching of the skin. 85 young individuals participated in an experiment. Sensory characteristics of the stimulation (pleasantness, intensity) and physiological changes (HR, HF, RMSSD, respiratory rate, SCL) were assessed during the stimulation periods. The most pleasant and intense skin sensations were reported in the slow stroking condition, followed by the rhythmic touching and attention condition. Slow stroking and rhythmic touching significantly decreased HR and increased HF, RMSSD, respiratory rate, and SCL compared to baseline and the attention condition. Pleasantness of the sensation in the slow stroking condition was largely independent from the evoked physiological changes and from the assessed trait-like characteristics; Bayesian analysis indicated the superiority of null hypothesis (i.e. lack of associations) for almost all cases. Although rhythmic touching is experienced as less pleasant and intense, it has a relaxing (parasympathetic) effect on cardiac activity that is comparable with the effect of slow stroking. Characteristics of the evoked skin sensation are not related to major dimensions of personality and body awareness.

A multichannel investigation of proprioceptive accuracy

Proprioceptive accuracy (PAc), i.e., the acuity of perception of the state of different parts of the motor system, shows substantial intraindividual differences, and is often considered a general ability. However, it is questionable whether there is an association between accuracies measured with different tests at different body sites. PAc with respect to both knee and elbow joints (joint position reproduction) and the flexors of the upper arms (weight discrimination) was measured in 87 young healthy individuals with regular physical activity across multiple indices. Expected and perceived performance was also assessed for each behavioral task. Frequentist and Bayesian analysis largely supported the idea that PAc with respect to various parts of the motor system are unrelated. No dominant-subdominant differences for actual performance were found; however, PAc for the dominant and subdominant limb were associated in many cases. Finally, perceived performance was related to expected but not to actual performance for all three proprioceptive modalities. In conclusion, actual accuracy of perception of the actual state of a part (i.e., joint, muscle) of the motor system cannot be generalized to other parts. Perceived accuracy, dominantly shaped by expectations, is independent from actual accuracy.

Placebo and nocebo interventions impact perceived but not actual proprioceptive accuracy

Changes in performance caused by positive and negative expectations (i.e., placebo and nocebo responses) were found to play an important role in many aspects of motor performance. This study aimed to test the impact of placebo/nocebo responses and the assumed moderating role of dispositional optimism and anxiety on proprioceptive accuracy, an essential aspect of motor functions. 78 undergraduate university students completed questionnaires assessing dispositional optimism, state anxiety, and motivation to cooperate, then were randomly assigned to three experimental groups. A sham subliminal electric stimulation was applied with claimed positive (placebo group, n = 26), negative (nocebo group, n = 26) or neutral (control group, n = 26) impact on proprioceptive accuracy. Proprioceptive accuracy was measured with active and passive versions of the Joint Position Reproduction task before and after the intervention. Expected and perceived changes in performance were also assessed; changes in state anxiety, optimism, and motivation to cooperate were used as control variables (covariates). Mixed analyses of variance indicated that the experimental manipulation did not affect actual proprioceptive accuracy but impacted expected and perceived performance. Adding the covariates to the models did not substantially change the results. Further, no significant association emerged between actual and perceived change in performance in the active test, and only a weak correlation was found in the passive test. Expected performance did not predict actual performance but predicted perceived performance in both tasks. The results suggest that only perceived (subjective) aspects of proprioceptive accuracy are susceptible to placebo and nocebo interventions.

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.

Interoceptive beliefs moderate the link between physiological and emotional arousal during an acute stressor

Growing work suggests that interoception, that is, representations of one's internal bodily changes, plays a role in shaping emotional experiences. Past studies primarily examine how behavioral accuracy in detecting interoceptive signals (interoceptive ability) relates to emotional states, with less work examining self-reported interoceptive facets such as the characterizations of one's interoceptive abilities (interoceptive sensibility) or evaluative beliefs about the value versus danger of interoceptive signals (interoceptive beliefs). However, existing studies rarely examine physiological reactivity, behavioral, and self-reported dimensions of interoception together in the same sample. As such, it remains unclear whether and how much individual differences in interoceptive facets uniquely and in interaction with physiological reactivity may matter for emotional experience. Herein, 250 healthy young adults completed a heartbeat detection task assessing interoceptive ability and questionnaire measures of interoceptive sensibility and beliefs during an initial laboratory visit. At a follow-up session, 227 participants returned to undergo an acute psychosocial stressor. Measures of physiological arousal such as preejection period (PEP) and heart rate variability were acquired throughout the stressor with self-reported emotions acquired immediately after. Linear regressions revealed that greater sympathetic nervous system reactivity (i.e., PEP), poorer interoceptive ability (i.e., accuracy), and less positive interoceptive beliefs were related to more intense high arousal emotions during the stressor. Importantly, across models, interoceptive beliefs was the only interoceptive facet to moderate the concordance between physiological and emotional arousal. Implications for psychological theories of emotion, stress, and interoception are discussed. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

A Primer on Interoception and its Importance in Psychiatry

Interoception is the perception of signals from inside the body. It plays a significant role in the nervous, cardiovascular, respiratory, gastrointestinal, genitourinary, and endocrine systems. It is also closely related to the autonomic nervous system and inflammatory pathways and plays a significant role in our optimal functioning. Recently, interoception has gained more attention in neuropsychiatric research. Anatomical and physiological aspects of interoception like relevant brain areas, the role of the vagus nerve, and the autonomic nervous system are gradually being understood. Different facets of interoception like interoceptive attention, detection, magnitude, discrimination, accuracy, awareness, and appraisal have been proposed and their assessments and importance are being evaluated. Further, interoception is often dysregulated or abnormal in psychiatric disorders. It has been implicated in the psychopathology, etiopathogenesis, clinical features and treatment of mood, anxiety, psychotic, personality and addiction-related disorders. This narrative review attempts to provide a nuanced understanding of the pathway(s), components, functions, assessments, and problems of interoception and will help us to detect its disturbances and evaluate its impact on psychiatric disorders, leading to a better perspective and management. This will also advance interoception-related research.

Temporal dynamics of interoceptive attention and positive and negative affect in adults engaging in disordered eating and nonsuicidal self-injury

OBJECTIVE

Interoception (the sense of the body's state) is associated with eating disorders and nonsuicidal self-injury, potentially through relationships with affect. We examined the relationship between interoceptive attention and both positive and negative affect.

METHODS

Participants (N = 128) who reported recent self-harm (i.e., disordered eating and/or non-suicidal self-injury) completed ecological momentary assessment for 16 days. Participants completed multiple daily assessments of affect and interoceptive attention. We then tested the temporal dynamic relationship between interoceptive attention and affect.

RESULTS

There was a relationship between positive affect and interoceptive attention such that people with higher average positive affect, and times when people were above their typical positive affect, were associated with higher interoceptive attention. There was a negative relationship between negative affect and interoceptive attention, such that people with higher average negative affect, and times when people were above their own typical negative affect, were associated with lower interoceptive attention.

CONCLUSIONS

Better mood may associate with greater willingness to attend to body sensations. Our findings support active inference models of interoception and highlight the importance of refining our understanding of the dynamic nature of interoception and its relationship with affect.

The measurement of proprioceptive accuracy: A systematic literature review

BACKGROUND

Proprioceptive accuracy refers to the individual's ability to perceive proprioceptive information, that is, the information referring to the actual state of the locomotor system, which originates from mechanoreceptors located in various parts of the locomotor system and from tactile receptors located in the skin. Proprioceptive accuracy appears to be an important aspect in the evaluation of sensorimotor functioning; however, no widely accepted standard assessment exists. In this systematic review, our goal was to identify and categorize different methods that are used to assess different aspects of proprioceptive accuracy.

METHODS

A literature search was conducted in 5 different databases (PubMed, SPORTDiscus, PsycINFO, ScienceDirect, and SpringerLink).

RESULTS

Overall, 1139 scientific papers reporting 1346 methods were included in this review. The methods assess 8 different aspects of proprioception: (a) the perception of joint position, (b) movement and movement extent, (c) trajectory, (d) velocity, and the sense of (e) force, (f) muscle tension, (g) weight, and (h) size. They apply various paradigms of psychophysics (i.e., the method of adjustment, constant stimuli, and limits).

CONCLUSION

As the outcomes of different tasks with respect to various body parts show no associations (i.e., proprioceptive accuracy is characterized by site-specificity and method-specificity), the appropriate measurement method for the task needs to be chosen based on theoretical considerations and/or ecological validity.

Do interoception and attending to the upper limbs affect body ownership and body representation in the grasp illusion?

Passively grasping an unseen artificial finger induces ownership over this finger and an illusory coming together of one's index fingers: a grasp illusion. Here we determine how interoceptive ability and attending to the upper limbs influence this illusion. Participants passively grasped an unseen artificial finger with their left index finger and thumb for 3 min while their right index finger, located 12 cm below, was lightly clamped. Experiment 1 (n = 30) investigated whether the strength of the grasp illusion (perceived index finger spacing and perceived ownership) is related to a person's level of interoceptive accuracy (modified heartbeat counting task) and sensibility (Noticing subscale of the Multidimensional Assessment of Interoceptive Awareness). Experiment 2 (n = 30) investigated the effect of providing verbal or tactile cues to guide participants' attention to their upper limbs. On their own, neither interoceptive accuracy and sensibility or verbal and tactile cueing had an effect on the grasp illusion. However, verbal cueing increased the strength of the grasp illusion in individuals with lower interoceptive ability. Across the observed range of interoceptive accuracy and sensibility, verbal cueing decreased perceived index spacing by 5.6 cm [1.91 to 9.38] (mean [95%CI]), and perceived ownership by ∼3 points on a 7-point Likert scale (slope -0.93 [-1.72 to -0.15]). Thus, attending to the upper limbs via verbal cues increases the strength of the grasp illusion in a way that is inversely proportional to a person's level of interoceptive accuracy and sensibility.

Somatosensory Deviance Detection ERPs and Their Relationship to Analogous Auditory ERPs and Interoceptive Accuracy

Abstract. Automatic deviance detection has been widely explored in terms of mismatch responses (mismatch negativity or mismatch response) and P3a components of event-related potentials (ERPs) under a predictive coding framework; however, the somatosensory mismatch response has been investigated less often regarding the different types of changes than its auditory counterpart. It is not known whether the deviance detection responses from different modalities correlate, reflecting a general prediction error mechanism of the central nervous system. Furthermore, interoceptive functions have been associated with predictive coding theory, but whether interoceptive accuracy correlates with deviance detection brain responses has rarely been investigated. Here, we measured ERPs to changes in somatosensory stimuli’s location and intensity and in sound intensity in healthy adults ( n = 34). Interoceptive accuracy was measured with a heartbeat discrimination task, where participants indicated whether their heartbeats were simultaneous or non-simultaneous with sound stimuli. We found a mismatch response and a P3a response to somatosensory location and auditory intensity changes, but for somatosensory intensity changes, only a P3a response was found. Unexpectedly, there were neither correlations between the somatosensory location deviance and intensity deviance brain responses nor between auditory and somatosensory brain responses. In addition, the brain responses did not correlate with interoceptive accuracy. The results suggest that although deviance detection in the auditory and somatosensory modalities are likely based on similar neural mechanisms at a cellular level, their ERP indexes do not indicate a linear association in sensitivity for deviance detection between the modalities. Furthermore, although sensory deviance detection and interoceptive detection are both associated with predictive coding functions, under these experimental settings, functional relationships were not observed. These results should be taken into account in the future development of theories related to human sensory functions and in extensions of the predictive coding theory in particular.