Heartbeat Perception Task Research Articles

Interoceptive processing deficit: A behavioral marker for subtyping Parkinson’s disease

BackgroundNon-motor symptoms in Parkinson's disease (PD), such as cognitive, emotional, autonomic and somatosensory alterations, are not ubiquitous but vary between the tremor dominant (TD) and postural instability/gait difficulty (PIGD) subtypes of the syndrome. Non-motor phenomena (e.g., anxiety, depression and apathy) have been related to representation of autonomic and somatosensory sensations (interoception), and recent findings suggest interoceptive deficits in PD. ObjectivesTo test whether interoceptive processing is differently affected in TD and PIGD phenotypes, by assessing both interoceptive accuracy and sensibility in PD patients with TD and PIGD subtypes, and in healthy controls. MethodsInteroceptive accuracy was measured by the heartbeat perception task requiring participants to count their own heartbeats in a given time interval. A time-estimation, control task was also administered asking participants to count the seconds in a set period of time. Interoceptive sensibility was assessed by a questionnaire of subjective interoception. Finally, the patients underwent measures of anxiety, depression, apathy and anhedonia, and impulsive-compulsive disturbances. ResultsThe main results showed reduced interoceptive accuracy and sensibility in TD patients relative to both PIGD patients and healthy controls. Reduced interoceptive accuracy of TD group was a reliable result since their performance on the time estimation control task was comparable to that of both PIGD patients and healthy controls. ConclusionsThese findings demonstrate that the behavioural assessment of different aspects of interoceptive processing can provide with a further marker for subtyping patients with PD.

Audio-visual sensory deprivation degrades visuo-tactile peri-personal space.

Self-perception is scaffolded upon the integration of multisensory cues on the body, the space surrounding the body (i.e., the peri-personal space; PPS), and from within the body. We asked whether reducing information available from external space would change: PPS, interoceptive accuracy, and self-experience. Twenty participants were exposed to 15 min of audio-visual deprivation and performed: (i) a visuo-tactile interaction task measuring their PPS; (ii) a heartbeat perception task measuring interoceptive accuracy; and (iii) a series of questionnaires related to self-perception and mental illness. These tasks were carried out in two conditions: while exposed to a standard sensory environment and under a condition of audio-visual deprivation. Results suggest that while PPS becomes ill defined after audio-visual deprivation, interoceptive accuracy is unaltered at a group-level, with some participants improving and some worsening in interoceptive accuracy. Interestingly, correlational individual differences analyses revealed that changes in PPS after audio-visual deprivation were related to interoceptive accuracy and self-reports of "unusual experiences" on an individual subject basis. Taken together, the findings argue for a relationship between the malleability of PPS, interoceptive accuracy, and an inclination toward aberrant ideation often associated with mental illness.

I see neither your Fear, nor your Sadness – Interoception in adolescents

Interoception describes the mapping of the body's internal landscape and has been connected to greater intensity of emotional experience. The goal of the current study was to explore the relationship between interoception and emotion face recognition in healthy adolescents. The heartbeat perception task was used to assess interoceptive accuracy(IAC) and participants were asked to recognize different facial expressions. EEG activity was recorded, providing data for the P100, the N170 and the P300 ERP components. Results indicated high sensitivity to negative affect, as well as low accuracy in the recognition of fear and sadness among adolescents high in IAC, reflected by amplitude modulations in the N170 and the P300. The interpretation of these results focus on the intensity experienced in negative facial emotions, modified by IAC, as well as on emotional valence and arousal. These findings emphasize the dynamic integration of body and mind for shaping emotion recognition in adolescence.

The effects of alcohol on heartbeat perception: Implications for anxiety

IntroductionIt is well established that some individuals self-medicate their anxiety with alcohol. Though much evidence exists that alcohol consumption can be negatively reinforcing, there remains uncertainty regarding what mediates the relationship between alcohol and anxiety. An unexplored possibility is that, for some, alcohol impairs interoceptive sensitivity (the ability to accurately perceive one's physiological state), thereby decreasing state anxiety. Consistent with this, highly accurate heartbeat perception is a risk factor both for elevated trait anxiety and anxiety disorders. However, the direct impact of alcohol on cardioceptive accuracy has not to our knowledge been previously examined. MethodsSixty-one social drinkers came to the lab in groups of 4–6 on two days spaced a week apart. Each participant was randomly assigned to receive alcoholic drinks targeting a BAC of 0.05% on one testing day and placebo drinks on the other, with the order counter-balanced. On both testing days, participants engaged in a Schandry heartbeat perception task on three occasions: at baseline, after an alcohol absorption period, and after physiological arousal was raised via exercise. ResultsFor men only, alcohol significantly impaired cardioceptive accuracy relative to a placebo at both low and high levels of arousal, with medium to large effect sizes. ConclusionsThough preliminary, this finding is consistent with the proposed hypothesis linking alcohol consumption and anxiety, at least for men. Future studies should directly examine whether, among individuals with anxiety disorders, cardioceptive sensitivity mediates the relationship between alcohol consumption and state anxiety.

The effect of mindful eating on subsequent intake of a high calorie snack

This study examined the effects of applying a mindful eating strategy during lunch on subsequent intake of a palatable snack. It also looked at whether this effect occurred due to improved memory for lunch and whether effects varied with participant gender, level of interoceptive awareness or sensitivity to reward. Participants (n = 51) completed a heartbeat perception task to assess interoceptive awareness. They were then provided with a lunch of 825 calories. Participants in the experimental group ate lunch while listening to an audio clip encouraging them to focus on the sensory properties of the food (e.g. its smell, look, texture). Those in the control group ate lunch in silence. Two hours later participants were offered a snack. They then completed a questionnaire assessing sensitivity to reward as well as other measures assessing various aspects of their memory for lunch. The results showed no significant difference in lunch intake between the two groups but participants in the experimental group consumed significantly less snack than those in the control group; mean = 112.30 calories (SD = 70.24) versus mean = 203.20 calories (SD = 88.05) respectively, Cohen's d = 1.14. This effect occurred regardless of participant gender or level of interoceptive awareness. There was also no significant moderation by sensitivity to reward although one aspect, reward interest, showed a trend towards significance. There was no evidence to indicate that the mindful eating strategy enhanced participants' memory for their lunch. Further research is needed to assess the long-term effects of this strategy, as well as establish the underlying mechanisms. Future work on the relationship between sensitivity to reward and the effects of mindful eating may also benefit from larger sample sizes.

I can feel my heartbeat: Dancers have increased interoceptive accuracy.

Interoception is the process of perceiving afferent signals arising from within the body including heart rate (HR), gastric signals, etc., and has been described as a mechanism crucially involved in the creation of self-awareness and selfhood. The heartbeat perception task is a tool to measure individuals' interoceptive accuracy (IAcc). IAcc correlates positively with measures of self-awareness and with attributes including emotional sensitivity, empathy, prosocial behavior, and efficient decision making. IAcc is only moderate in the general population, and attempts to identify groups of people who might have higher IAcc due to their specific training (e.g., yoga, meditation) have not been successful. However, a recent study with musicians suggests that those trained in the arts might exhibit high IAcc. Here, we tested IAcc in 20 professional dancers and 20 female control participants on a heartbeat perception task. Dancers had a higher IAcc, and this effect was independent of their lower heart rates (a proxy measure of physical fitness), counting ability, and knowledge about HR. An additional between-groups analysis after a median split in the dancer group (based on years of dance experience) showed that junior dancers' IAcc differed from controls, and senior dancers' IAcc was higher than both junior dancers and controls. General art experience correlated positively with IAcc. No correlations were found between IAcc and questionnaire measures of empathy, emotional experience, and alexithymia. These findings are discussed in the context of current theories of interoception and emotion-highlighting the features of arts training that might be related to IAcc.

Improvement of Interoceptive Processes after an 8-Week Body Scan Intervention.

Objective: Interoceptive processes are defined as ability to detect sensations arising within the body. There is a growing body of research investigating ways of improving interoceptive processes. One promising approach increasing the attention to bodily sensations is the body scan (BS), a method stemming from mindfulness-based stress reduction. Research so far revealed only heterogenous findings of meditational practice and mindfulness-based stress reduction on interoceptive processes. Even more importantly, there is no study considering the effect of an 8-week BS intervention on interoceptive processes and the distinguishable subdomains of interoception. Therefore, the main objective of this research is to examine the effects of a BS intervention on different interoceptive subdomains over 8 weeks of training in two different samples.Methods: In study 1, healthy participants executed a 20 min standardized audiotaped BS in the BS intervention group (n = 25) each day over 8 weeks. The control group (n = 24) listened to an audio book for the same amount of time. In study 2, the BS group (n = 18) was compared to an inactive control group (n = 18). In both studies, three measurement points were realized and interoceptive accuracy (IAc) – using a heartbeat perception task – as well as interoceptive sensibility (IS) – using confidence ratings for the heartbeat perception task and the subscale ‘interoceptive awareness’ of the Eating Disorder Inventory-2 (EDI-2) – were assessed.Results: In study 1, we found, as a descriptive trend, IAc and confidence ratings to be increased irrespective of the condition. However, post hoc analysis revealed a significant improvement of IAc between T1 and T3 in the BS intervention only. IS revealed to be unaffected by the interventions. In study 2, we observed a significant positive effect of the BS intervention on IAc and confidence ratings compared to the inactive controls. As in study 1, IS (EDI-2) was unaffected by the intervention.Discussion: The results highlight the fact that interoception can be improved by long-term interventions focusing on bodily signals. Further studies might focus on clinical samples showing deficits in interoceptive processes and could use other bodily systems for measurement (e.g., respiratory signals) as well methods manipulating body ownership.

Can you feel the body that you see? On the relationship between interoceptive accuracy and body image

Interoception and exteroception for body signals are two different ways of perceiving the self: the first from within, the second from outside. We investigated the relationship between Interoceptive Accuracy (IAcc) and external perception of the body and we tested if seeing the body from an external perspective can affect IAcc. Fifty-two healthy female subjects performed a standard heartbeat perception task to assess the IAcc, before and after the Body Image Revealer (BIR), which is a body perception task designed to assess the different aspects of body-image. The performance of the lower IAcc group in the heartbeat perception task significantly improved after the exteroceptive task. These findings highlight the relations between interoceptive and exteroceptive body-representations, supporting the view that these two kinds of awareness are linked and interact with each other.

Atypical Self-Focus Effect on Interoceptive Accuracy in Anorexia Nervosa.

Background: Interoceptive abilities are known to be affected in anorexia nervosa (AN). Previous studies could show that private self-focus can enhance interoceptive accuracy (IAcc) in healthy participants. As body dissatisfaction is high in AN, confrontation with bodily features such as the own face might have a directly opposed effect in AN. Whether patients with AN can benefit from self-focus in their IAcc and whether this pattern changes over the time-course of cognitive behavioral therapy was investigated in this study.Methods: Fifteen patients with AN from the Psychosomatic Clinic in Windach were assessed three times in the time course of a standardized cognitive-behavioral therapy. They were compared to 15 controls, recruited from Ulm University and tested in a comparable setting. Both groups performed the heartbeat perception task assessing IAcc under two conditions either enhancing (“Self”) or decreasing (“Other”) self-focused attention. Furthermore, body dissatisfaction was assessed by a subscale of the Eating Disorder (ED) Inventory 2.Results: Patients with AN scored higher in IAcc when watching others’ faces as compared to one’s own face while performing the heartbeat perception task. The opposite pattern was observed in controls. IAcc remained reduced in AN as compared to controls in the time-course of cognitive-behavioral therapy, while body-dissatisfaction improved in AN. High body dissatisfaction was related to poorer IAcc in the “Self” condition.Conclusions: Our findings suggest that using self-focused attention reduces IAcc in AN while the opposite pattern was observed in controls. Confronting anorexic patients with bodily features might increase body-related avoidance and therefore decrease IAcc. The current study introduces a new perspective concerning the role of interoceptive processes in AN and generates further questions regarding the therapeutic utility of methods targeting self-focus in the treatment of AN.

Interoception and Positive Symptoms in Schizophrenia.

The present study focuses on the multifaceted concept of self-disturbance in schizophrenia, adding knowledge about a not yet investigated aspect, which is the interoceptive accuracy. Starting from the assumption that interoceptive accuracy requires an intact sense of self, which otherwise was proved to be altered in schizophrenia, the aim of the present study was to explore interoceptive accuracy in a group of schizophrenia patients, compared to healthy controls. Furthermore, the possible association between interoceptive accuracy and patients’ positive and negative symptomatology was assessed. To pursue these goals, a group of 23 schizophrenia patients and a group of 23 healthy controls performed a heartbeat perception task. Patients’ symptomatology was assessed by means of the Positive and Negative Syndrome Scale (PANSS). Results demonstrated significantly lower interoceptive accuracy in schizophrenia patients compared to healthy controls. This difference was not accounted for participants’ age, BMI, anxiety levels, and heart rate. Furthermore, patients’ illness severity, attention and pharmacological treatment did not influence their interoceptive accuracy levels. Interestingly, a strong positive relation between interoceptive accuracy and positive symptoms severity, especially Grandiosity, was found. The present results demonstrate for the first time that interoceptive accuracy is altered in schizophrenia. Furthermore, they prove a specific association between interoceptive accuracy and positive symptomatology, suggesting that the symptom Grandiosity might be protective against an altered basic sense of self in patients characterized by higher sensibility to their inner bodily sensations.

Decreased interoceptive awareness in patients with substance use disorders

Introduction: The current study was prepared based on the assumption that awareness of the interoceptive processes may be disturbed in addicted individuals.Methods: The participants in the study included 84 abstinent male inpatients who were addicted to alcohol (n = 33), heroin (n = 29), or synthetic cannabinoids (n = 22) according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR), and 35 healthy male volunteers. Interoceptive awareness (IA) was measured using the heartbeat perception (HBP) task. Addiction severity was assessed using the addiction profile index (API). Alexithymia was assessed using the Toronto alexithymia scale (TAS-20).Results: Patients addicted to alcohol, heroin, or synthetic cannabinoids had similar IA, and their HBP scores were significantly lower than those of healthy control subjects. There was a significant negative correlation between HBP scores and TAS-20 subscores, thus indicating difficulties in identifying feelings. HBP scores were not significantly correlated with API scores. API scores were significantly correlated with total alexithymia scores and subscores, thus indicating difficulties in identifying and describing feelings.Discussion: As our main finding, a decrease in IA in addicted patients in comparison to healthy controls may provide support for the hypothesis that awareness of the interoceptive processes may be disturbed in addiction.

The Relationship Between Interoception and Metacognition

Abstract. Recently, Garfinkel and Critchley (2013) proposed to distinguish between three facets of interoception: interoceptive sensibility, interoceptive accuracy, and interoceptive awareness. This pilot study investigated how these facets interrelate to each other and whether interoceptive awareness is related to the metacognitive awareness of memory performance. A sample of 24 healthy students completed a heartbeat perception task (HPT) and a memory task. Judgments of confidence were requested for each task. Participants filled in questionnaires assessing interoceptive sensibility, depression, anxiety, and socio-demographic characteristics. The three facets of interoception were found to be uncorrelated and interoceptive awareness was not related to metacognitive awareness of memory performance. Whereas memory performance was significantly related to metamemory awareness, interoceptive accuracy (HPT) and interoceptive awareness were not correlated. Results suggest that future research on interoception should assess all facets of interoception in order to capture the multifaceted quality of the construct.

Know thyself: Exploring interoceptive sensitivity in Parkinson's disease

BackgroundAlthough Parkinson's disease (PD) is defined by its motor symptoms, it is now well recognised that cognitive, affective and emotion domains are also impaired. The pathophysiology of these disabling non-motor symptoms (NMS) remains unclear; recently the involvement of limbic areas, including the insula, in the neurodegenerative process has been suggested to have a key role. These areas, and the insula in particular, are also been suggested as key regions for interoception; interoceptive sensitivity (IS) is a measure of the accuracy of perception of sensations from inside the body related to the function of internal organs. ObjectivesTo evaluate IS in PD patients by means of a well-established task: the heartbeat perception task. Moreover, we evaluated possible correlations between IS and psychological, affective and disease-related characteristics as well as fatigue perception in PD patients. MethodsTwenty PD patients and 20 healthy subjects (HS) were included and underwent the heartbeat perception task. An extensive evaluation of motor, non-motor, affective and emotion domains was carried out. ResultsPD patients showed lower IS than HS (0.58±0.2 vs 0.72±0.1; p=0.04). PD reported higher scores in scales assessing depression (Hamilton depression scale: 8.7±5.8 vs 6.2±7.5; p=0.04); anhedonia (Snaith–Hamilton Pleasure Scale: 26.8±9.7 vs 15.4±2.9; p=<0.001) and apathy (Apathy Evaluation Scale: 35.8±8.6 vs 27.8±6.8; p=0.008). No significant correlations were detected between IS and motor, non-motor, affective and emotion symptoms. ConclusionsPD patients have reduced interoceptive sensitivity. Future studies are encouraged to evaluate the importance of interoception in understanding the pathophysiology of affective/emotional symptoms in PD.

Joint effects of sensory feedback and interoceptive awareness on conscious error detection: Evidence from event related brain potentials

Error awareness has been argued to depend on sensory feedback and interoceptive awareness (IA) (Ullsperger, Harsay, Wessel, & Ridderinkhof, 2010). We recorded EEG while participants performed a speeded Go/No-Go task in which they signaled error commission. Visibility of the effector was manipulated, while IA was measured with a heartbeat perception task. The late Pe was larger for aware than unaware errors. The ERN was also found to be modulated by error awareness, but only when the hand was visible, suggesting that its sensitivity to error awareness depends on the availability of visual sensory feedback. Only when the response hand was visible, the late Pe amplitude to aware errors correlated with IA, suggesting that sensory feedback and IA synergistically contribute to the emergence of error awareness. These findings underscore the idea that several sources of information accumulate in time following action execution in order to enable errors to break through and reach awareness.

Diminished Interoceptive Awareness in Fibromyalgia Syndrome

ABSTRACTSensitivity to signals arising within the body (interoceptive awareness) has been implicated in emotion processing; interindividual differences in interoceptive awareness modulate both subjective and physiological indicators of emotional experience and the regulation of emotion-related behaviors. This study investigated interoceptive awareness in patients with fibromyalgia syndrome (FMS), a chronic pain condition accompanied by various affective symptoms. Interoceptive awareness was assessed in 45 FMS patients and 31 healthy individuals using a heartbeat perception task. Cognitive performance, comorbid psychiatric disorders and medication use were assessed as possible confounding variables. Concerning the primary outcome, patients exhibited markedly reduced heartbeat perception compared to healthy individuals. Moreover, there was an inverse relationship between interoceptive awareness and FMS symptom severity. Reduced interoceptive awareness may be involved in the affective aspects of FMS pathology. Poor access to bodily signals may restrict patients´ ability to integrate these signals during emotional processing, which, by extension, may preclude optimal emotional self-regulation.

Attenuated sensitivity to the emotions of others by insular lesion.

The insular cortex has been considered to be the neural base of visceral sensation for many years. Previous studies in psychology and cognitive neuroscience have accumulated evidence indicating that interoception is an essential factor in the subjective feeling of emotion. Recent neuroimaging studies have demonstrated that anterior insular cortex activation is associated with accessing interoceptive information and underpinning the subjective experience of emotional state. Only a small number of studies have focused on the influence of insular damage on emotion processing and interoceptive awareness. Moreover, disparate hypotheses have been proposed for the alteration of emotion processing by insular lesions. Some studies show that insular lesions yield an inability for understanding and representing disgust exclusively, but other studies suggest that such lesions modulate arousal and valence judgments for both positive and negative emotions. In this study, we examined the alteration in emotion recognition in three right insular and adjacent area damaged cases with well-preserved higher cognitive function. Participants performed an experimental task using morphed photos that ranged between neutral and emotional facial expressions (i.e., anger, sadness, disgust, and happiness). Recognition rates of particular emotions were calculated to measure emotional sensitivity. In addition, they performed heartbeat perception task for measuring interoceptive accuracy. The cases identified emotions that have high arousal level (e.g., anger) as less aroused emotions (e.g., sadness) and a case showed remarkably low interoceptive accuracy. The current results show that insular lesions lead to attenuated emotional sensitivity across emotions, rather than category-specific impairments such as to disgust. Despite the small number of cases, our findings suggest that the insular cortex modulates recognition of emotional saliency and mediates interoceptive and emotional awareness.

Investigating the relationship between interoceptive accuracy, interoceptive awareness, and emotional susceptibility.

Interoception, the sense of the physiological condition of the body, provides a basis for subjective feelings and emotions. Anterior insular cortex activity represents the state of the body and varies according to personality traits, such as emotional susceptibility (ES)—the tendency to experience feelings of discomfort and vulnerability when facing emotionally-laden stimuli. The accuracy of perceiving one's own bodily signals, or interoceptive accuracy (IAc), can be assessed with the heartbeat perception task (HPT), which is the experimental measure used by most of the existing research on interoception. However, IAc is only one facet of interoception. Interoceptive awareness (IAw) is the conscious perception of sensations from inside the body, such as heart beat, respiration, satiety, and the autonomic nervous system sensations related to emotions, which create the sense of the physiological condition of the body. We developed an Italian version of the recent self-report Multidimensional Assessment of Interoceptive Awareness (MAIA), tested its psychometric properties (reliability, dimensionality, and construct validity), and examined its relationship to ES, as assessed using the Emotional Susceptibility Scale, in a sample (n = 321) of healthy Italian psychology students (293 females, mean age: 20.5 years). In a subgroup of females (n = 135), we measured IAc with the HPT. We used a series of correlation/regression analyses to examine the complex interplay between the three constructs. We provide further evidence for a substantial independence of the IAc and IAw measures, confirming previous reports and current theoretical models that differentiate between IAc and IAw. Our analyses elucidate the complex relationship between distinct dimensions of IAw and ES, highlighting the need for continued efforts to shed more light on this topic.

Psychophysiology of duration estimation in experienced mindfulness meditators and matched controls.

Recent research suggests that bodily signals and interoception are strongly related to our sense of time. Mindfulness meditators train to be aware of their body states and therefore could be more accurate at interval timing. In this study, n = 22 experienced mindfulness meditators and n = 22 matched controls performed both, an acoustic and a visual duration reproduction task of 8, 14, and 20 s intervals, while heart rate and skin conductance were continuously assessed. In addition, participants accomplished a heart beat perception task and two selective attention tasks. Results revealed no differences between meditators and controls with respect to performance in duration reproduction or attentional capacities. Additionally no group difference in heart beat perception scores was found. Across all subjects, correlational analyses revealed several associations between performance in the duration reproduction tasks and psychophysiological changes, the latter being also related to heart beat perception scores. Furthermore, former findings of linearly increasing cardiac periods and decreasing skin conductance levels during the auditory duration estimation task (Meissner and Wittmann, 2011) could be replicated, and these changes could also be observed during a visual duration reproduction task. In contrast to our earlier findings, the heart beat perception test was not related with timing performance. Overall, although experienced meditators did not differ from matched controls with respect to duration reproduction and interoceptive awareness, this study adds significantly to the emerging view that time perception is related to autonomic regulation and awareness of body states.

Interoceptive sensitivity facilitates both antecedent- and response-focused emotion regulation strategies

The ability to perceive bodily signals (interoceptive sensitivity) modulates emotional experience. However, there is scarce evidence that interoceptive sensitivity also modulates the use of emotion regulation strategies. The present study investigated whether individual differences in interoceptive sensitivity are associated with the habitual use of two main emotion regulation strategies: reappraisal (antecedent-focused) and suppression (response-focused). All participants (N=402) completed the Emotion Regulation Questionnaire and underwent the heartbeat perception task. Individuals with higher interoceptive sensitivity showed both greater habitual reappraisal and suppression use compared to those with lower interoceptive sensitivity. These findings suggest that better detection of ones' bodily signals facilitates the selection and implementation of antecedent-focused as well as response-focused emotion regulation strategies.

Inflammation-induced pain sensitization in men and women: does sex matter in experimental endotoxemia?

A role of the innate immune system is increasingly recognized as a mechanism contributing to pain sensitization. Experimental administration of the bacterial endotoxin lipopolysaccharide (LPS) constitutes a model to study inflammation-induced pain sensitization, but all existing human evidence comes from male participants. We assessed visceral and musculoskeletal pain sensitivity after low-dose LPS administration in healthy men and women to test the hypothesis that women show greater LPS-induced hyperalgesia compared with men. In this randomized, double-blind, placebo-controlled crossover study, healthy men (n = 20) and healthy women using oral contraceptives (n = 20) received an intravenous injection of 0.4 ng/kg body weight LPS or placebo. Pain sensitivity was assessed with established visceral and musculoskeletal pain models (ie, rectal pain thresholds; pressure pain thresholds for different muscle groups), together with a heartbeat perception (interoceptive accuracy) task. Plasma cytokines (tumor necrosis factor-α and interleukin-6) were measured along with state anxiety at baseline and up to 6-hour postinjection. Lipopolysaccharide application led to significant increases in plasma cytokines and state anxiety and decreased interoceptive awareness in men and women (P < 0.001, condition effects), with more pronounced LPS-induced cytokine increases in women (P < 0.05, interaction effects). Although both rectal and pressure pain thresholds were significantly decreased in the LPS condition (all P < 0.05, condition effect), no sex differences in endotoxin-induced sensitization were observed. In summary, LPS-induced systemic immune activation leads to visceral and musculoskeletal hyperalgesia, irrespective of biological sex. These findings support the broad applicability of experimental endotoxin administration as a translational preclinical model of inflammation-induced pain sensitization in both sexes.