Search

BACKGROUND: Parasympathetic tone activity (PTA) in response to nociceptive stimulus in conscious non-sedated horses is unknown. OBJECTIVES: Study PTA, heart rate (HR), and horse grimace scale (HGS) at rest and during mechanical nociceptive stimulation. ANIMALS: Ninety healthy young adult horses (females, males): 30 each of Friesians, Quarter Horses, and Warmbloods. METHODS: Prospective control study. The study consisted of habituation to equipment (Day 1), baseline recordings (Days 2 and 3), and nociceptive testing applying mild pressure to the metacarpus (Day 4). Parasympathetic tone, HR, and HGS were recorded simultaneously on Days 2 to 4. Each study lasted 30 minutes and was done in triplicate at 3 different time points per day. RESULTS: Baseline PTA was not different among breeds. It decreased in Warmbloods and Quarter Horses during placement of the stimulus device without stimulation (P

Background: This study aims to examine the relationship between resting vagal‐related heart rate variability (HRV) parameters and heart rate (HR) with resting metabolic rate (RMR) and respiratory exchange ratio (RER) in young adults. Methods: A total of 74 young adults (22 ± 2 years old, 51 women) were included in this cross‐sectional study. HRV was assessed using a HR monitor, whereas RMR and RER were determined by indirect calorimetry. Results: Linear regression analyses showed a positive association between HR and RER in women (standardized β = 0.384, p = 0.008), while negative associations were observed between vagal‐related HRV parameters and RER in women (β ranged from −0.262 to −0.254, all p ≤ 0.042). No significant association was found between the abovementioned physiological parameters in men. Conclusion: Here, we show that HR is positively associated with RER in young women but not in men, while vagal‐related HRV parameters are inversely related to RMR, therefore suggesting a potential sexual dimorphism between cardiac rhythm and its relationship with markers of cardiometabolic health status. Trial Registration: ClinicalTrials.gov identifier: NCT02365129. [ABSTRACT FROM AUTHOR]

Background Methods Key Results Conclusions & Inferences Diabetic gastroenteropathy can cause significant diagnostic challenges. Still, it remains unknown if measures of extraintestinal autonomic function reflect diabetic gastroenteropathy. We aimed to assess the associations between (1) gastrointestinal symptoms and motility measures and (2) gastrointestinal symptoms/motility measures and extraintestinal autonomic markers.We included 81 persons with type 1 or type 2 diabetes (65% female, mean age 54) with gastrointestinal symptoms and autonomic neuropathy. The Gastroparesis Cardinal Symptom Index (GCSI) and the Gastrointestinal Symptom Rating Scale (GSRS) assessed gastrointestinal symptoms. The wireless motility capsule (Smartpill™) assessed panenteric transit times and motility indices. Cardiovascular reflex tests (VAGUS™) and cardiac vagal tone (eMotion Faros) estimated cardiovascular autonomic neuropathy, while the SUDOSCAN™ evaluated sudomotor function.Proximal gastrointestinal symptoms were positively associated with the gastric motility index (GCSI: 1.18 (1.04–1.35), p = 0.01; GSRS: 1.15 (1.03–1.29), p = 0.02; median ratio (95% CI)), while only satiety correlated with gastric emptying time (1.24 (1.03–1.49), p = 0.02). Diarrhea was associated with decreased small bowel transit time (0.93 (0.89–0.98), p = 0.005), while constipation were associated with prolonged colonic transit time (1.16 (1.03–1.31), p = 0.02). Gastrointestinal symptoms increased with the degree of abnormal cardiovascular reflex tests (GCSI: 0.67 (0.16–1.19), p = 0.03; GSRS: 0.87 (0.30–1.45), p = 0.01; mean difference (95% CI)) but not with motility measures. Cardiac vagal tone and sudomotor function were not associated with gastrointestinal markers.Gastrointestinal and extraintestinal autonomic measures were not associated. However, proximal gastrointestinal symptoms were associated with the gastric motility index and cardiovascular reflex tests. Hence, the latter may contribute to evaluating whether proximal gastrointestinal symptoms are autonomically derived. [ABSTRACT FROM AUTHOR]

Behavioral inhibition (BI), a temperamental trait first described by Jerome Kagan, is characterized by wariness to unfamiliar persons and novel situations. BI is a moderately stable trait, with biological and genetic underpinnings. Kagan's methodology for assessing BI is widely used in humans. Although this paradigm could be readily translated for use in nonhuman primates, thereby increasing generalizability from nonhuman primates to humans and fortifying evidence that BI is evolutionarily conserved, researchers have not done so. To address this, this study utilized a modified version of Kagan's paradigm to assess behaviors and biological markers of BI in nonhuman primates. Over the first 5 weeks of life, nursery-reared rhesus monkeys (Macaca mulatta; N = 12) were rated using the standardized Infant Behavior Assessment Scale for nonhuman primates on measures related to BI (consolability, irritability, struggle, and predominant state). Three months later, behavioral assessments were made in relation to a novel playroom, an unfamiliar peer, and a variety of attention-grabbing, unfamiliar stimuli, followed by the introduction of a human stranger. Behaviors from Kagan's studies of BI in toddlers (freezing, exploration, and latency to approach) and physiological measures related to BI (heart rate) were assessed. Random effects models showed that subjects rated high in temperamental BI spent less time exploring the environment and socializing with peers and more time freezing (an indication of anxiety in rhesus monkeys). These findings suggest that Kagan's paradigm is readily adapted for use in nonhuman primates and support the utility of rhesus monkeys as translational models for assessing the causes and consequences of human BI. Public Significance Statement: Behavioral inhibition (BI; sometimes termed "shyness") can be debilitating, as it is often associated with low self-esteem, stress, anxiety, and depression. Studies show that BI early in life is associated with later mood disorders. Using adapted methodology first established in humans, findings from this study indicate that trait-like interindividual stability in BI-related behaviors and physiological responses is exhibited by nonhuman primates. This suggests that BI is evolutionarily conserved, likely serving a functional purpose, and that nonhuman primate models can be utilized to investigate developmental outcomes related to BI. [ABSTRACT FROM AUTHOR]

We investigated the influence of family alliance on infants' vagal tone. Physiological studies have shown that the quality of mother–infant interactions can influence infants' vagal tone, which is an important indicator of emotion regulation. Although research has shown that family‐level relationships have a unique impact on child development, little is known about the association between the quality of mother–father–infant interactions and infants' physiological regulation during a family interaction task. We hypothesized that infants in families with a greater family alliance, that is, degree of coordination reached by parents when completing a task, will have higher vagal tone than will infants in families with a lower family alliance. We also hypothesized that this association would be mediated by the amount of intrusive and withdrawn parental behaviors and by the impact of these behaviors on the infant during mother–father–infant interactions. This study included 82 parents with their 3‐month‐old infants. Results showed that family alliance was associated with infants' vagal tone during triadic interactions and that the impact of intrusive/withdrawn parental behaviors on the interaction partially mediated this association. [ABSTRACT FROM AUTHOR]

The neurovisceral integration model proposes that information flows bidirectionally between the brain and the heart via the vagus nerve, indexed by vagally mediated heart rate variability (vmHRV). Voluntary reduction in breathing rate (slow‐paced breathing, SPB, 5.5 Breathing Per Minute (BPM)) can enhance vmHRV. Additionally, prefrontal transcranial direct current stimulation (tDCS) can modulate the excitability of the prefrontal region and influence the vagus nerve. However, research on the combination of SPB and prefrontal tDCS to increase vmHRV and other cardiac (heart rate (HR) and blood pressure) and peripheral (skin conductance) indices is scarce. We hypothesized that the combination of 20 min of SPB and prefrontal tDCS would have a greater effect than each intervention in isolation. Hence, 200 participants were divided into four groups: active tDCS with SPB, active tDCS with 15 BPM breathing, sham tDCS with SPB, and sham tDCS with 15 BPM breathing. Regardless of the tDCS condition, the 5.5 BPM group showed a significant increase in vmHRV over 20 minutes and significant decreases in HR at the first and second 5‐min epochs of the intervention. Regardless of breathing condition, the active tDCS group exhibited higher HR at the fourth 5‐min epoch of the intervention than the sham tDCS group. No other effects were observed. Overall, SPB is a robust technique for increasing vmHRV, whereas prefrontal tDCS may produce effects that counteract those of SPB. More research is necessary to test whether and how SPB and neuromodulation approaches can be combined to improve cardiac vagal tone. This study explored, for the first time, the temporal course of physical (slow‐paced breathing, SPB) and neuromodulation (prefrontal tDCS) interventions to enhance cardiac vagal tone. Through a well‐sampled between‐subjects sham‐controlled design, this study found that SPB has a very rapid impact on increasing vagally mediated HRV and decreasing HR and blood pressure. Prefrontal tDCS, on the contrary, has a slower effect, mainly increasing heart rate suggesting more sympathetic arousal. Unexpectedly, the combination did not yield beneficial results. [ABSTRACT FROM AUTHOR]

Objective: To consider the possible role of the vagus nerve (VN) in the pathophysiology of sleep bruxism (SB) and introduce a multimodal protocol of transcutaneous auricular stimulation of the VN in the treatment of SB patients. Methods: Ten patients with SB underwent four sessions of electric transcutaneous auricular vagus nerve stimulation (ta-VNS) in specific auricular areas. The patients were advised to manually stimulate the same areas between sessions. Masticatory muscle activity and sleep parameters were measured by a polysomnography (PSG) before and after the treatment. Heart rate variability (HRV) parameters were measured during each stimulation. Results: PSG analysis revealed a statistically significant reduction in tonic SB index and tonic contraction time. HRV parameters showed a statistically significant increase in mean values of the vagal tone after each session of stimulation. No side effect was reported. Conclusion: The stimulation of the VN might have a role in the treatment of SB. [ABSTRACT FROM AUTHOR]

The article discusses the author's experience participating in an Ironman event in Austria at the age of 66, highlighting the challenges faced due to illness and poor weather during training. The text delves into the physiological aspects of endurance performance, including issues like dehydration, glycogen depletion, and cardiac arrhythmias. The author reflects on the mental and physical demands of the event, emphasizing the importance of adaptability and perseverance in completing the race. The article also touches on the implications of aging, fitness, and endurance training on overall health and well-being. [Extracted from the article]

Introduction: We developed a low‐cost, user‐friendly complementary research tool to evaluate autonomic nervous system (ANS) activity at varying levels of cognitive workload. This was achieved using visual stimuli as cognitive tasks, administered through a specially designed computer‐based test battery. Methods: To assess sympathetic stress responses, skin conductance response (SCR) was measured, and electrocardiograms (ECG) were recorded to evaluate heart rate variability (HRV), an indicator of cardiac vagal tone. Twenty‐five healthy adults participated in the study. SCR and ECG recordings were made during both tonic and phasic phases using a computer‐based system designed for visual stimuli. Participants performed a button‐pressing task upon seeing the target stimulus, and the relationship between reaction time (RT) and cognitive load was evaluated. Results: Analysis of the data showed higher skin conductance levels (SCLs) during tasks compared to baseline, indicating successful elicitation of sympathetic responses. RTs differed significantly between simple and cognitive tasks, increasing with mental load. Additionally, significant changes in vagally mediated HRV parameters during tasks compared to baseline highlighted the impact of cognitive load on the parasympathetic branch of the ANS, thereby influencing the brain–heart connection. Conclusion: Our findings indicate that the developed research tool can successfully induce cognitive load, significantly affecting SCL, RTs, and HRV. This validates the tool's effectiveness in evaluating ANS responses to cognitive tasks. [ABSTRACT FROM AUTHOR]

Background: This study examines the psychophysiological differences between virtual reality (VR) and real archery. It explores whether VR archery induces heart rate (HR), heart rate variability (HRV), and breathing rates similar to those experienced in real archery. Additionally, the study assesses differences in perceived anxiety, difficulty, confidence, rate of perceived exertion (RPE), and shooting performance between the two modalities, providing insights into the efficacy of VR as a training tool for archery. Methods: Twenty‐two (women: 8) individuals aged 20–24 participated in the study. We first recorded individuals' resting HR, HRV, and breathing rates during baseline. Afterward, participants shot 10 real and virtual arrows from 18 m, whereas their HR, HRV, and breathing rate were measured, each lasting 4 min. Performance in VR and real archery was determined separately as the sum of the shots. We performed paired sample t‐tests to compare individuals' performance, psychological, and psychophysiological responses recorded during VR and real arrow shooting. Afterward, we compared percentage changes between VR and real archery. Results: Results showed that HR and root mean square of successive differences (RMMSD) were significantly higher during real archery compared to virtual archery. In addition, VR archery led to a greater percentage change in RMSSD compared to real archery. Participants reported greater RPE and perceived difficulty after real archery. Performance was also higher during VR archery than real archery. Conclusions: Consequently, the results of the present study illustrated that VR, and real archery might lead to different autonomic response patterns in terms of vagal activity. [ABSTRACT FROM AUTHOR]

Cooperation, as a mutual collaboration, is a defining feature of human social life. Individual characteristics can influence cooperation. Recent studies have shown a quadratic relationship between cardiac vagal tone (CVT), an index of self‐regulation, and prosocial behaviors. Individual differences in cooperation might also vary as a function of people's environmental sensitivity (ES), i.e., may be influenced by individual differences in the perception and processing of inner and external stimuli. We tested the direct and interactive effect of CVT and ES on cooperative behaviors in two independent samples. We measured heart rate and engagement in cooperative acts in 80 young adults (M = 23.61; SD = 1.60) who were also asked to self‐report on ES. We found an inverted‐U relationship between CVT and cooperative behaviors. ES, on the other hand, did not predict differences in cooperative behaviors but moderated the relationships between CVT and cooperation, although the magnitude of this result was small. Specifically, only among individuals with higher ES cooperative behaviors change as a function of CVT. Highly sensitive individuals with lower or higher CVT, were less cooperative than low sensitive ones. Subsequently, we replicated the same study design in a second sample of 88 undergraduate students (M = 23.69; SD = 4.91). Once again, we found evidence supporting the presence of an inverted‐U relationship between CVT and cooperative behaviors, and we also found that ES moderated the relationships between the quadratic CVT term and cooperation. Our findings add new evidence on physiological self‐regulation as an underlying mechanism of prosocial behaviors, in particular cooperation. In two independent samples, our results showed a quadratic relationship between cardiac vagal tone (CVT) and cooperation. We found that this relationship is moderated by environmental sensitivity (ES). Specifically, only among individuals with higher ES, cooperative behaviors change as a function of CVT. To make the world more cooperative, people should learn how to regulate especially when they are highly sensitive. [ABSTRACT FROM AUTHOR]

Chronic loneliness and low perceived social support have been recognized as risk factors for both mental and cardiovascular disorders. It has been proposed that their link to psychophysiological problems may involve changes in parasympathetic activity. However, the exact underlying psychopathological mechanisms and the moderating effects of gender are still not thoroughly examined. Thus, the present study investigated associations between perceived social functioning and resting vagal tone in the context of potential cognitive and subclinical mediators and gender differences. Three hundred twenty‐five young adults (aged 18–35, 180 women) underwent an electrocardiogram measurement of 6‐minute resting heart rate variability (HRV). They also completed questionnaires assessing loneliness, perceived social support, social cognitive biases, depressive and social anxiety symptoms, and general mental health. In men, HRV was significantly and negatively associated with poorer perceived social functioning, depressive symptoms, and self‐reported social cognitive biases, while in women, there was a quadratic link between HRV and depressive symptoms and HRV and general mental health. Moderated mediation analysis revealed that depressive symptoms fully mediated the relationship between perceived social functioning and HRV in men. The results suggest that decreased resting vagal tone in lonely individuals is linked to depressive symptomatology rather than to specific social cognitive biases and that this association is significant only in men. While previous work on the relationship between loneliness and parasympathetic activity has yielded mixed results, the present study provides evidence for an association between reduced resting vagal tone, loneliness, and perceived social support. Importantly, we showed that this association was mostly related to subclinical depressive symptoms and was only observed in men, which may help better understand individual differences related to maladaptive physiological processes in lonely individuals. [ABSTRACT FROM AUTHOR]

The identification of acute cardioprotective strategies against myocardial ischemia/reperfusion (I/R) injury that can be applied in the catheterization room is currently an unmet clinical need and several interventions evaluated in the past at the pre-clinical level have failed in translation. Autonomic imbalance, sustained by an abnormal afferent signalling, is a key component of I/R injury. Accordingly, there is a strong rationale for neuromodulation strategies, aimed at reducing sympathetic activity and/or increasing vagal tone, in this setting. In this review we focus on cervical vagal nerve stimulation (cVNS) and on transcutaneous auricular vagus nerve stimulation (taVNS); the latest has the potential to overcome several of the issues of invasive cVNS, including the possibility of being used in an acute setting, while retaining its beneficial effects. First, we discuss the pathophysiology of I/R injury, that is mostly a consequence of the overproduction of reactive oxygen species. Second, we describe the functional anatomy of the parasympathetic branch of the autonomic nervous system and the most relevant principles of bioelectronic medicine applied to electrical vagal modulation, with a particular focus on taVNS. Then, we provide a detailed and comprehensive summary of the most relevant pre-clinical studies of invasive and non-invasive VNS that support its strong cardioprotective effect whenever there is an acute or chronic cardiac injury and specifically in the setting of myocardial I/R injury. The potential benefit in the emerging field of post cardiac arrest syndrome (PCAS) is also mentioned. Indeed, electrical cVNS has a strong anti-adrenergic, anti-inflammatory, antioxidants, anti-apoptotic and pro-angiogenic effect; most of the involved molecular pathways were already directly confirmed to take place at the cardiac level for taVNS. Pre-clinical data clearly show that the sooner VNS is applied, the better the outcome, with the possibility of a marked infarct size reduction and almost complete left ventricular reverse remodelling when VNS is applied immediately before and during reperfusion. Finally, we describe in detail the limited but very promising clinical experience of taVNS in I/R injury available so far. [ABSTRACT FROM AUTHOR]

Many studies have examined the effects of meditation practice focused on the normal breath on vagal tone with mixed results. Heart Rhythm Meditation (HRM) is a unique meditation form that engages in the deep slow full breath, and puts the focus of attention on the heart. This form of breathing likely stimulates the vagus nerve with greater intensity. The purpose of this study was (a) to examine how the practice of HRM affects vagal activity as measured by heart rate variability (HRV); and (b) to examine how it affects participants' well-being. 74 participants signed consent agreeing to: (a) take a six-week course to learn the practice of HRM; (b) engage in a daily practice for 10 weeks; (c) have their heart rate variability read through ECG technology and to take two validated well-being instruments at the beginning and end of the 10 weeks; and (d) participate in a focus group interview examining their perceptions of how the practice affected their well-being. 48 participants completed the study. Quantitative findings show the effect of the practice of HRM approached significance for multiple measures of HRV and vagal tone. An increase in well-being scores for those who did the meditation more than 10-minutes per day did meet statistical significance. Qualitative data indicate: (a) the positive effects of HRM on stress and well-being; (b) the development of a more expanded sense of self; and (c) an increased awareness of the interconnection of the body-heart-emotions and HRM's role in emotion regulation. [ABSTRACT FROM AUTHOR]

Abstract Background Parasympathetic tone activity (PTA) in response to nociceptive stimulus in conscious non‐sedated horses is unknown. Objectives Study PTA, heart rate (HR), and horse grimace scale (HGS) at rest and during mechanical nociceptive stimulation. Animals Ninety healthy young adult horses (females, males): 30 each of Friesians, Quarter Horses, and Warmbloods. Methods Prospective control study. The study consisted of habituation to equipment (Day 1), baseline recordings (Days 2 and 3), and nociceptive testing applying mild pressure to the metacarpus (Day 4). Parasympathetic tone, HR, and HGS were recorded simultaneously on Days 2 to 4. Each study lasted 30 minutes and was done in triplicate at 3 different time points per day. Results Baseline PTA was not different among breeds. It decreased in Warmbloods and Quarter Horses during placement of the stimulus device without stimulation (P

Melatonin, a pineal gland hormone closely associated with the circadian rhythm, has been trending over the past years as an over-the-counter medication to aid with sleep disturbances. Although generally believed to be safe, recent studies show negative inotropic and chronotropic effects on the heart rate and blood pressure in humans. Several studies suggested that melatonin induces cardiac vagal tone and affects heart rate and mean arterial pressure. Limited literature is currently available on the effects of melatonin beyond its sleep function. We present a case of a healthy 22-year-old male who visited the emergency department reporting palpitations and dizziness following the ingestion of 20 mg of melatonin. Subsequent examinations revealed marked bradycardia. Fortunately, the patient experienced spontaneous resolution of the bradycardia without necessitating intervention after a few hours of observation, and he was observed and discharged. [ABSTRACT FROM AUTHOR]

Higher self‐reported rumination, a common form of trait perseverative cognition, is linked with lower resting heart rate variability (HRV), which indicates poorer cardiac function and greater disease risk. A meta‐analysis and systematic review indicated that in samples with fewer European Americans, the association of rumination with both heart rate and blood pressure was stronger. Thus, trait rumination may be more strongly associated with resting HRV among ethnically minoritized populations. The current study investigated whether differences in the association of self‐reported rumination with resting HRV varied by ethnicity in a sample (N = 513; Mage = 19.41; 226 Women) of self‐identified African Americans (n = 110), Asian Americans (n = 84), and European Americans (n = 319). Participants completed a five‐minute baseline period to assess resting HRV, followed by the Ruminative Responses Scale, which contains three facets of rumination including brooding, depressive, and reflective rumination. On average, Asian Americans reported higher levels of rumination relative to European Americans. African Americans had higher resting HRV than Asian Americans. Adjusting for covariates, higher self‐reported rumination was significantly associated with lower resting HRV in both African and Asian Americans, but not significantly so in European Americans. This finding was consistent for brooding and reflective, but not depressive rumination. Overall, this study lends insight into a psychological mechanism—rumination—that may impact health disparities among ethnically minoritized individuals, contributing to an understanding of how stress gets under the skin among such minoritized populations. [ABSTRACT FROM AUTHOR]

This article discusses three cases of post-surgical spontaneous paroxysmal hypothermia (SPH), a condition characterized by recurrent episodes of hypothermia and mental confusion related to a hypothalamic lesion. The cases involve patients who underwent surgery for various hypothalamus disorders and experienced episodes of hypothermia, bradycardia, and other symptoms. The article highlights the importance of prompt diagnosis and appropriate interventions for effective treatment of SPH. It also suggests that changes in sympatho-vagal balance may play a role in the cardiac consequences of SPH. [Extracted from the article]

Adults with type 1 diabetes (T1D) have an elevated risk for cardiovascular disease (CVD) compared with the general population. HbA1c is the primary modifiable risk factor for CVD in T1D. Fewer than 1% of patients achieve euglycemia (<5.7% HbA1c). Ketogenic diets (KD; ≤50 g carbohydrate/day) may improve glycemia and downstream vascular dysfunction in T1D by reducing HbA1c and insulin load. However, there are concerns regarding the long-term CVD risk from a KD. Therefore, we compared data collected in a 60-day window in an adult with T1D on exogenous insulin who consumed a KD for 10 years versus normative values in those with T1D (T1D norms). The participant achieved euglycemia with an HbA1c of 5.5%, mean glucose of 98 [5] mg/dL (median [interquartile range]), 90 [11]% time-in-range 70–180 mg/dL (T1D norms: 1st percentile for all), and low insulin requirements of 0.38 ± 0.03 IU/kg/day (T1D norms: 8th percentile). Seated systolic blood pressure (SBP) was 113 mmHg (T1D norms: 18th percentile), while ambulatory awake SBP was 132 ± 15 mmHg (T1D target: <130 mmHg), blood triglycerides were 69 mg/dL (T1D norms: 34th percentile), low-density lipoprotein was 129 mg/dL (T1D norms: 60th percentile), heart rate was 56 beats/min (T1D norms: >1SD below the mean), carotid-femoral pulse wave velocity was 7.17 m/s (T1D norms: lowest quartile of risk), flow-mediated dilation was 12.8% (T1D norms: >1SD above mean), and cardiac vagal baroreflex gain was 23.5 ms/mmHg (T1D norms: >1SD above mean). Finally, there was no indication of left ventricular diastolic dysfunction from echocardiography. Overall, these data demonstrate below-average CVD risk relative to T1D norms despite concerns regarding the long-term impact of a KD on CVD risk. NEW & NOTEWORTHY: Adults with type 1 diabetes (T1D) have a 10-fold higher risk for cardiovascular disease (CVD) compared with the general population. We assessed cardiovascular health metrics in an adult with T1D who presented with a euglycemic HbA1c after following a ketogenic diet for the past 10 years. Despite concerns about the ketogenic diet increasing CVD risk, the participant exhibited below-average CVD risk relative to others with T1D when considering all outcomes together. [ABSTRACT FROM AUTHOR]

Bradyarrhythmias including sinus bradycardia and atrioventricular (AV) block are frequently encountered in endurance athletes especially at night. While these are well tolerated by the young athlete, there is evidence that generally from the fifth decade of life onward, such arrhythmias can degenerate into pathological symptomatic bradycardia requiring pacemaker therapy. For many years, athletic bradycardia and AV block have been attributed to high vagal tone, but work from our group has questioned this widely held assumption and demonstrated a role for intrinsic electrophysiological remodeling of the sinus node and the AV node. In this article, we argue that bradyarrhythmias in the veteran athlete arise from the cumulative effects of exercise training, the circadian rhythm and aging on the electrical activity of the nodes. We consider contemporary strategies for the treatment of symptomatic bradyarrhythmias in athletes and highlight potential therapies resulting from our evolving mechanistic understanding of this phenomenon. [Display omitted] [ABSTRACT FROM AUTHOR]

Patients with cirrhosis often exhibit cardiac autonomic dysfunction (CAD), characterized by enhanced cardiac sympathetic activity and diminished cardiac vagal tone, leading to increased morbidity and mortality. This study delineates the cellular and molecular mechanisms associated with altered neuronal activities causing cirrhosis-induced CAD. Biliary and nonbiliary cirrhotic rats were produced by common bile duct ligation (CBDL) and intraperitoneal injections of thioacetamide (TAA), respectively. Three weeks after CBDL or TAA injection, the assessment of heart rate variability revealed autonomic imbalance in cirrhotic rats. We observed increased excitability in stellate ganglion (SG) neurons and decreased excitability in intracardiac ganglion (ICG) neurons in cirrhotic rats compared to sham-operated controls. Additionally, threshold, rheobase, and action potential duration exhibited opposite alterations in SG and ICG neurons, along with changes in afterhyperpolarization duration. A- and M-type K⁺ channels were significantly downregulated in SG neurons, while M-type K⁺ channels were upregulated, with downregulation of the N- and L-type Ca2⁺ channels in the ICG neurons of cirrhotic rats, both in transcript expression and functional activity. Collectively, these findings suggest that cirrhosis induces an imbalance between cardiac sympathetic and parasympathetic neuronal activities via the differential regulation of K+ and Ca2+ channels. Thus, cirrhosis-induced CAD may be associated with impaired autonomic efferent functions within the homeostatic reflex arc that regulates cardiac functions. [ABSTRACT FROM AUTHOR]

Accumulating evidence suggests that interactions between the brain and gut microbiota significantly impact brain function and mental health. In the present study, we aimed to investigate whether young, healthy adults without psychiatric diagnoses exhibit differences in metabolic stool and microbiota profiles based on depression/anxiety scores and heart rate variability (HRV) parameters. Untargeted nuclear magnetic resonance-based metabolomics was used to identify fecal metabolic profiles. Results were subjected to multivariate analysis through principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA), and the metabolites were identified through VIP score. Metabolites separating asymptomatic and symptomatic groups were acetate, valine, and glutamate, followed by sugar regions, glutamine, acetone, valerate, and acetoacetate. The main metabolites identified in high vagal tone (HVT) and low vagal tone (LVT) groups were acetate, valerate, and glutamate, followed by propionate and butyrate. In addition to the metabolites identified by the PLS-DA test, significant differences in aspartate, sarcosine, malate, and methionine were observed between the groups. Levels of acetoacetate were higher in both symptomatic and LVT groups. Valerate levels were significantly increased in the symptomatic group, while isovalerate, propionate, glutamate, and acetone levels were significantly increased in the LVT group. Furthermore, distinct abundance between groups was only confirmed for the Firmicutes phylum. Differences between participants with high and low vagal tone suggest that certain metabolites are involved in communication between the vagus nerve and the brain. [ABSTRACT FROM AUTHOR]

Background Cardiac vagal tone is an indicator of parasympathetic nervous system functioning, and there is increasing interest in its relation to antisocial behavior. It is unclear however whether antisocial individuals are characterized by increased or decreased vagal tone, and whether increased vagal tone is the source of the low heart rate frequently reported in antisocial populations. Methods Participants consisted of four groups of community-dwelling adolescent boys aged 15.7 years: (1) controls, (2) childhood-only antisocial, (3) adolescent-only antisocial, and (4) persistently antisocial. Heart rate and vagal tone were assessed in three different conditions: rest, cognitive stressor, and social stressor. Results All three antisocial groups had both lower resting heart rates and increased vagal tone compared to the low antisocial controls across all three conditions. Low heart rate partially mediated the relationship between vagal tone and antisocial behavior. Conclusions Results indicate that increased vagal tone and reduced heart rate are relatively broad risk factors for different developmental forms of antisocial behavior. Findings are the first to implicate vagal tone as an explanatory factor in understanding heart rate – antisocial behavior relationships. Future experimental work using non-invasive vagus nerve stimulation or heart rate variability biofeedback is needed to more systematically evaluate this conclusion. [ABSTRACT FROM AUTHOR]

Objective: Winter-over expeditioners in Antarctica are challenged by various environmental and psycho-social stress factors, which may induce psychophysiological changes. The autonomic nervous system (ANS) plays a crucial role in the adaptation process under stress. However, the relationship between ANS activity and the mood states of expeditioners remains largely unexplored. This study aims to uncover the pattern of ANS adjustment under extreme Antarctic environments and provide new insights into the correlations between ANS activity and mood state changes, which may provide scientific data for medical interventions. Methods: Fourteen expeditioners at Zhongshan Station participated in this study. The study was conducted during four representative periods: pre-Antarctica, Antarctica-1 (pre-winter), Antarctica-2 (winter), and Antarctica-3 (summer). The heart rate variability (HRV) of the expeditioners was continuously measured for 24 hours to evaluate ANS activity. Plasma levels of catecholamines were tested by ELISA. Mood states were assessed by the Profile of Mood States (POMS) scale. Results: HRV analysis showed a disturbance of ANS during winter and summer periods. For frequency domain parameters, very low frequency (VLF), low frequency (LF), high frequency (HF), and total power (TP) significantly increased during the second half of the mission. Especially, LF/HF ratio decreased during summer, indicating the predominance of vagal tone. Results of the time domain analysis showed increased heart rate variability during the austral winter and summer. Plasma epinephrine (E) significantly increased during residence in Antarctica. Compared with pre-Antarctica, the vigor, depression, and anger scores of the expeditioners decreased significantly during the austral summer. Notably, the depression score showed a moderate positive correlation with LF/HF, while weak negative correlations with other HRV indicators, including TP, VLF, and LF. Anger score showed a moderate positive correlation with LF/HF and weak negative correlations with the average normal-to-normal (NN) interval, and the root mean square of differences between adjacent RR intervals (RMSSD). Plasma E level weakly correlated with the average NN interval. Conclusion: Prolonged residence in Antarctica increased the ANS activities and shifted the cardiac autonomic modulation towards vagal predominance. The alteration of HRV correlated with mood states and plasma epinephrine levels. [ABSTRACT FROM AUTHOR]

Stephen Porges’s polyvagal theory proposes to integrate various scientific disciplines such as anatomy, physiology, psychophysiology, evolutionary and developmental biology, social sciences and psychotherapy together with special evolutionary features of the vagus nerve in mammals putatively claimed by polyvagal conjectures. This specifically involves linking neuroanatomical hypotheses about the vagus nerve with social and psychological concepts, especially regarding socioemotional behavior and conditions of extreme stress. These concepts have particularly found increasing popularity among trauma therapists, and have sometimes been described as groundbreaking, as in the last issue of this journal (Ackermann, 2024; Grassmann, 2024; Rahm & Meggyesy, 2024). However, there is a broad state-of-the-knowledge consensus among experts that the fundamental physiological hypotheses of the polyvagal theory are untenable and must be considered largely refuted. Furthermore, the major psychological constituents of polyvagal theory – attachment, co-regulation, social engagement, and intero ceptive processes beyond conscious awareness – each predate polyvagal speculations by decades; there is also a depth of thought and literature readily available that does not require physiological justifications for their uses in psychology or psychotherapy. For those desiring a more biological understanding of these processes, there are other models of explanation, integrating the entire nervous system, that correspond with current understanding of body and mind. [ABSTRACT FROM AUTHOR]

Besides health monitoring, a regular check of dairy heifers' growth rate is desirable, but it is rarely done because procedures that require restraint and handling can be associated with substantial stress for both animals and farmers. Inexperienced heifers, especially if they are highly responsive to humans, may find restraint and handling potentially aversive. This study investigated whether training heifers of different age and responsiveness toward humans (RTH), through operant conditioning, could reduce stress in animals, ease close contact and handling, and be feasible in terms of farmers' effort. We assessed 60 Holstein heifers of 2 age classes (young, n = 29, 291 ± 39 d; old, n = 31, 346 ± 62 d) according to the avoidance distance test and classified them as confident (n = 20), neutral (n = 21), or nonconfident (n = 19). Half of the heifers of each age and RTH class were trained (n = 29), whereas the other half was not (n = 31). The trained heifers were subjected to target training for 8 sessions and positively reinforced with feed to allow being touched on the muzzle, rump, and perineum. If a heifer refused positive reinforcement, the trainer stepped back as negative reinforcement. In the last week of the experiment, the effect of training on the reaction to handling was assessed in all heifers. We measured heart rate, root mean square of successive interbeat interval differences (RMSSD), and fecal cortisol metabolites (FCMet). The presence of behavioral distress signs was recorded as well. The avoidance distance test was performed a second time 24 h after the measuring session. All of the trained heifers, regardless of RTH class, successfully accomplished the target training task in 6 sessions, each spending on average 25.3 s per session. All of the trained heifers allowed touches on the rump and perineum at the end of the fourth session. Training nonconfident heifers required more time compared with the others. Trained heifers showed higher RMSSD than nontrained heifers (14.2 vs. 16.9 ms, respectively), indicating a lower vagal tone, and thus, a slightly lower stress level than nontrained heifers. Training did not lead to differences in HR, FCMet, or presence of stress behavioral signs. Nonconfident heifers had the highest mean baseline FCMet values compared with neutral and confident heifers (38.4 vs. 30.3 vs. 29.1 ng/g, respectively). Nonconfident heifers also showed the lowest value of FCMet 12 h after the measuring session (36.7 vs. 44.6 vs. 49.7 ng/g), likely due to a decreased responsiveness of the adrenal gland to a stressor. The average avoidance distance decreased between the beginning and the end of the experiment, especially for neutral and nonconfident heifers, regardless of whether they were trained or not. These results show how using operant conditioning on some heifers not only decreased their vagal tone, but also reduced the responsiveness to humans of all the animals, trained and not trained; in the latter case, this reduction was through nonassociative learning, such as habituation. [ABSTRACT FROM AUTHOR]

Cooperation is crucial in classrooms for positive interactions among pupils, but the factors influencing children's cooperative behaviors remain debated. This study explores the impact of cardiac vagal tone (CVT), a measure of physiological self-regulation, and cognitive control on cooperation among 109 primary school students. Heart rate variability was used to assess self-regulation, and cognitive control was evaluated through an AX-Continuous Performance Task. Cooperative behavior was measured with a child-friendly Stag Hunt game. Results showed that moderate CVT is related to increased cooperative actions, but no direct relationship between cognitive control types and cooperation was found. However, an interaction effect indicated that moderate CVT particularly boosts cooperation in children who employ proactive cognitive control. These findings emphasize the need to develop physiological self-regulation skills to enhance cooperative behavior in educational settings, supporting better social, and emotional well-being, and learning outcomes. [ABSTRACT FROM AUTHOR]

The importance of psychopathy for perpetration and maintenance of intimate partner violence (IPV) has been speculated. However, less is known about whether psychopathy would explain a psychophysiological response (cardiorespiratory and electrodermal) of IPV perpetrators dealing with acute stressors. Therefore, we first aimed to assess whether IPV perpetrators (n = 58) showed differences in psychopathic traits and their psychophysiological response to acute stress compared to nonviolent men (n = 53). Second, we examined in both groups whether psychopathic traits would explain a psychophysiological response when dealing with acute laboratory stress. Our results revealed that IPV perpetrators differed from controls in all the psychopathic traits, scoring higher on all psychopathy scales. Moreover, IPV perpetrators showed lower total respiratory sinus arrhythmia (RSA) levels than controls. Finally, regarding high total psychopathy scores, factor 1 and affective facet entailed low RSA levels in both groups and scoring high in lifestyle facet of factor 2 explained reduced heart rate (HR) changes in response to acute stress in both groups. All these results highlighted that a reduced vagal tone could be characteristic of psychopathic traits, especially for the affective facet of psychopathy. Therefore, it would be important to incorporate biological markers in combination with psychological measurements to clearly diagnose IPV perpetrators before starting intervention programs. This would increase our ability to improve IPV intervention therapeutic targets and reduce risk of recidivism. [ABSTRACT FROM AUTHOR]

Background: An 8-month-old male was presented for Chiropractic care with parental concerns primarily related to sleep, muscle strength and digestion. In addition to these stated concerns, his parents were concerned about sleep, excessive gagging and vomiting on solid food, hypersensitivity to touch and a regression in skill levels. Hypotonicity and breastfeeding issues were also flagged as problematic. Intervention: The infant was placed on a Chiropractic care plan, whereby he was managed using Diversified and Activator methods, in addition to spinal adjusting and peripheral adjusting, all modified to be appropriate for his age and tensile strength. Outcomes: Significant positive changes were noted across all the stated areas of concern, concomitant with Chiropractic care. While the infant continued under Chiropractic care after the period of the initial care plan, the changes meant parents were able to work with the chiropractor to resolve issues relating to hypersensitivities, hypertonicity, feeding, sleeping, mood and more. Conclusion: This case report shows multi-system improvements in the infant's physiology and development, and no other interventions were introduced during his time under care. This may provide a rationale for future studies examining sympathetic and specifically vagal tone, in infants under Chiropractic care and how this might contribute to mood, digestion and development.! [ABSTRACT FROM AUTHOR]

Children with disruptive mood dysregulation disorder have difficulties with emotion regulation and recognition which impacts their social functioning. Due to its recent definition, there is limited information on the neural mechanisms of this disorder. This exploratory study examined the role of autonomic heart regulation in children with disruptive mood dysregulation disorder, motivated by suggestions of reduced autonomic regulation (measured by heart rate variability) associated with psychiatric disorders in adults and children. The cross-sectional design sampled two groups of children, one with disruptive mood dysregulation disorder (n = 15; 14 male) and the other with typical development (n = 15; 14 male). Heart rate variability, facial emotion recognition accuracy and speed, and prosody were measured. There were no significant differences in heart rate variability between the two groups before, or during, the tasks. However, children with disruptive mood dysregulation disorder experienced significantly greater difficulty recognising fear in faces compared to controls and confused other negatively valenced emotions. There was also a significant negative correlation between heart rate variability and prosody modulation (verbal expression of emotion) in the control group, a relationship that was absent in the disruptive mood dysregulation disorder group. These results suggest that atypical autonomic regulation during emotionally evocative situations and difficulty with facial emotion recognition may contribute to the challenges experienced by children with disruptive mood dysregulation disorder. This is valuable knowledge for psychologists, which can contribute to individualised, effective, and comprehensive care that addresses the child's emotional, social, and relational well-being. [ABSTRACT FROM AUTHOR]

Simple Summary: COVID-19, with persistent and new onset of symptoms, such as fatigue, post-exertional malaise, and cognitive dysfunction that impact everyday functioning, is referred to as long-COVID under the general category of post-acute sequelae of the SARS-CoV-2 infection (PASC). It includes a wide range of signs and symptoms that can last weeks, months, or even years after infection, most of which are attributable to dysfunctions of the neurovegetative system. The causative mechanisms are still unknown, but autoimmunity and the production of autoantibodies targeting self-antigens via the molecular mimicry phenomenon seem to have a role. Here we evaluated the presence of autoantibodies against two proteins of vagal nuclei sharing a peptide with SARS-CoV-2 spike glycoprotein in sera from ongoing symptomatic COVID-19 patients (long-COVID) with cardiorespiratory symptoms, subjects vaccinated without a history of SARS-CoV-2 infection, and subjects not vaccinated without a history of SARS-CoV-2. Putative autoantibodies are present in both long-COVID-19 and vaccinated groups, suggesting that both viral infection and vaccination may trigger autoreactivity. However, the presence of autoantibodies is not sufficient for triggering autoimmunity, and other predisposing conditions must co-occur. Therefore, it is necessary to run further investigations to clarify the complex mechanisms involved in the development of long-COVID, providing knowledge which may offer further information for the prevention and treatment of the disease. As reported by the World Health Organization (WHO), about 10–20% of people have experienced mid- to long-term effects following SARS-CoV-2 infection, collectively referred to as post-COVID-19 condition or long-COVID, including some neurovegetative symptoms. Numerous findings have suggested that the onset of these neurovegetative symptoms upon viral infection may be caused by the production of autoantibodies through molecular mimicry phenomena. Accordingly, we had previously demonstrated that 22 of the human proteins sharing putatively immunogenic peptides with SARS-CoV-2 proteins are expressed in the dorsal motor nucleus and nucleus ambiguous. Therefore, if molecular mimicry occurs following severe forms of COVID-19, there could be transitory or permanent damage in some vagal structures, resulting in a lower vagal tone and all the related clinical signs. We investigated the presence of autoantibodies against two proteins of vagal nuclei sharing a peptide with SARS-CoV-2 spike glycoprotein using an immunoassay test on blood obtained from patients with cardiorespiratory symptoms in patients affected by ongoing symptomatic COVID-19 (long-COVID), subjects vaccinated without a history of SARS-CoV-2 infection, and subjects not vaccinated without a history of SARS-CoV-2 infection. Interestingly, putative autoantibodies were present in both long-COVID-19 and vaccinated groups, opening interesting questions about pathogenic mechanisms of the disease. [ABSTRACT FROM AUTHOR]

The rising prevalence of cardiovascular disease underscores the growing significance of heart failure (HF). Pathophysiological insights into HF highlight the dysregulation of the autonomic nervous system (ANS), characterized by sympathetic overactivity and diminished vagal tone, impacting cardiovascular function. Heart rate recovery (HRR), a metric measuring the heart's ability to return to its baseline rate post-exertion, plays a crucial role in assessing cardiovascular health. Widely applied across various cardiovascular conditions including HF, coronary artery disease (CAD), and arterial hypertension (HTN), HRR quantifies the difference between peak and recovery heart rates. Given its association with elevated sympathetic tone and exercise, HRR provides valuable insights into the perspective of HF, beyond effort tolerance, reaching toward prognostic and mortality indicators. Incorporating HRR into cardiovascular evaluations enhances our understanding of autonomic regulation in HF, offering potential implications for prognostication and patient management. This review addresses the significance of HRR in HF assessment, analyzing recently conducted studies, and providing a foundation for further research and clinical application. [ABSTRACT FROM AUTHOR]

Drawing upon the well-documented impact of long-term heart rate variability biofeedback (HRVB) on psychophysiological responses, this study seeks to explore the short-term effects arising from a single HRVB session during and after paced breathing exercise. The research aligns with the neurovisceral integration model, emphasizing the link between heart rate variability (HRV) levels and cognitive performance. Therefore, a randomized controlled trial employing a between-subjects design was conducted with 38 participants. Each participant was assigned to either the paced breathing intervention group or the spontaneous breathing control group. The study assessed various parameters such as cardiac vagal tone, evaluated through vagally mediated HRV measures, and working memory, measured using the N-back task. Additionally, participants' affective states were assessed through self-reported questionnaires, specifically targeting attentiveness, fatigue, and serenity. The results notably reveal enhancements in the working memory task and an elevated state of relaxation and attention following the HRVB session, as evidenced by higher averages of correct responses, serenity and attentiveness scores. However, the findings suggest that this observed improvement is not influenced by changes in cardiac vagal tone, as assessed using a simple mediation analysis. In conclusion, this study presents promising insights into the impact of a single HRVB session, laying the foundation for future research advancements in this domain. [ABSTRACT FROM AUTHOR]

Patients with major depressive disorder (MDD) have an increased risk for cardiac events. This is partly attributed to a disbalance of the autonomic nervous system (ANS) indicated by a reduced vagal tone and a (relative) sympathetic hyperactivity. However, in most studies, heart rate variability (HRV) was only examined while resting. So far, it remains unclear whether the dysbalance of the ANS in patients with MDD is restricted to resting or whether it is also evident during sympathetic and parasympathetic activation. The aim of this study was to compare the responses of the ANS to challenges that stimulated the sympathetic and, respectively, the parasympathetic nervous systems in patients with MDD. Forty-six patients with MDD (female 27 (58.7%), mean age 44 ± 17 years) and 46 healthy controls (female 26 (56.5%), mean age 44 ± 20 years) underwent measurement of time- and frequency-dependent domains of HRV at rest, while standing (sympathetic challenge), and during slow-paced breathing (SPB, vagal, i.e., parasympathetic challenge). Patients with MDD showed a higher heart rate, a reduced HRV, and a diminished vagal tone during resting, standing, and SPB compared to controls. Patients with MDD and controls responded similarly to sympathetic and vagal activation. However, the extent of modulation of the ANS was impaired in patients with MDD, who showed a reduced decrease in the vagal tone but also a reduced increase in sympathetic activity when switching from resting to standing. Assessing changes in the ANS during sympathetic and vagal activation via respective challenges might serve as a future biomarker and help to allocate patients with MDD to therapies like HRV biofeedback and psychotherapy that were recently found to modulate the vagal tone. [ABSTRACT FROM AUTHOR]

Introduction: Prior investigations into post-COVID dysautonomia often lacked control groups or compared affected individuals solely to healthy volunteers. In addition, no data on the follow-up of patients with SARS-CoV-2-related autonomic imbalance are available. Methods: In this study, we conducted a comprehensive clinical and functional follow-up on healthcare workers (HCWs) with former mild COVID-19 (group 1, n = 67), to delineate the trajectory of post-acute autonomic imbalance, we previously detected in a case-control study. Additionally, we assessed HCWs for which a test before SARS-CoV-2 infection was available (group 2, n = 29), who later contracted SARS-CoV-2, aiming to validate findings from our prior case-control investigation. We evaluated autonomic nervous system heart modulation by means of time and frequency domain heart rate variability analysis (HRV) in HCWs during health surveillance visits. Short-term electrocardiogram (ECG) recordings, were obtained at about 6, 13 months and both at 6 and 13 months from the negative SARS-CoV-2 naso-pharyngeal swab (NPS) for group 1 and at about 1-month from the negative NPS for group 2. HCWs who used drugs, had comorbidities that affected HRV, or were hospitalized with severe COVID-19 were excluded. Results: Group 1 was split into three subgroups clinically and functionally followed at, about 6 months (subgroup-A, n = 17), 13 months (subgroup-B, n = 37) and both at 6 and 13 months (subgroup-C, n = 13) from the negative SARS-CoV-2 NPS. In subgroup-A, at 6-month follow-up compared with baseline, the spectral components in the frequency domain HRV parameters, showed an increase in normalized high frequency power (nHF) (t = 2.99, p = 0.009), a decrease in the normalized low frequency power (nLF) (t = 2.98, p = 0.009) and in the LF/HF ratio (t = 3.13, p = 0.006). In subgroup B, the comparison of the spectral components in the frequency domain HRV parameters, at 13-month follow-up compared with baseline, showed an increase in nHF (t = 2.54, p = 0.02); a decrease in nLF (t = 2.62, p = 0.01) and in the LF/HF ratio (t = 4.00, p = 0.0003). In subgroup-C, at both 6 and 13-month follow-ups, the spectral components in the frequency domain HRV parameters were higher than baseline in nHF (t = 2.64, p = 0.02 and (t = 2.13, p = 0.05, respectively); lower in nLF (t = 2.64, p = 0.02 and (t = 2.13, p = 0.05, respectively), and in LF/HF (t = 1.92, p = 0.08 and (t = 2.43, p = 0.03, respectively). A significant proportion of HCWs reported persistent COVID-19 symptoms at both the 6 and 13-month followups, seemingly unrelated to cardiac autonomic balance. In group 2 HCWs, at 1-month follow-up compared with baseline, the spectral components in the frequency domain HRV parameters, showed a decrease in nHF (t = 2.19, p = 0.04); an increase in nLF (t = 2.15, p = 0.04) and in LF/HF (t = 3.49, p = 0.002). Conclusion: These results are consistent with epidemiological data suggesting a higher risk of acute cardiovascular complications during the first 30 days after COVID-19. The SARS-CoV-2 associated autonomic imbalance in the postacute phase after recovery of mild COVID-19 resolved 6 months after the first negative SARS-CoV-2 NPS. However, a significant proportion of HCWs reported long-term COVID-19 symptoms, which dot not seems to be related to cardiac autonomic balance. Future research should certainly further test whether autonomic imbalance has a role in the mechanisms of long-COVID syndrome. [ABSTRACT FROM AUTHOR]

Background: Disruptive mood dysregulation disorder (DMDD) is characterised by severe emotion regulation difficulties, particularly anger and irritability, in children. Despite the impact of attachment on emotional and behavioural regulation, the link between attachment style and DMDD is under-researched. Aim: This study investigated whether attachment style and parasympathetic regulation differentiate the response profiles to frustrating conditions between children diagnosed with DMDD and controls. Setting: Participants were assessed at schools in Johannesburg, Gauteng, South Africa. Methods: Thirty participants were divided into two matched groups (nDMDD = 15; nControl = 15) and assessed. Respiratory sinus arrhythmia (RSA) and heart period were measured during an Affective Posner Task, inducing frustration. Attachment style was assessed using the Attachment Style Classification Questionnaire for children. Parents of children with DMDD completed a social interaction problems questionnaire. Results: The DMDD group showed a higher prevalence of avoidant attachment style (p = 0.013) compared to controls. Both groups displayed adaptive vagal withdrawal and recovery during the task (p = 0.005; p = 0.021). Controls had significantly higher heart period throughout the assessment (game 1: p = 0.006; game 2: p = 0.013; game 3: p = 0.007). In the DMDD group, lower vagal tone during frustration correlated with more social interaction problems (p = 0.049). Conclusion: The study demonstrates a potential link between attachment style and altered physiological state in children with DMDD. Contribution: The findings provide insight into possible atypical vagal regulation of the heart and avoidant attachment styles in DMDD, highlighting potential therapeutic and intervention targets.

ABSTRACT Background This study examines the psychophysiological differences between virtual reality (VR) and real archery. It explores whether VR archery induces heart rate (HR), heart rate variability (HRV), and breathing rates similar to those experienced in real archery. Additionally, the study assesses differences in perceived anxiety, difficulty, confidence, rate of perceived exertion (RPE), and shooting performance between the two modalities, providing insights into the efficacy of VR as a training tool for archery. Methods Twenty‐two (women: 8) individuals aged 20–24 participated in the study. We first recorded individuals’ resting HR, HRV, and breathing rates during baseline. Afterward, participants shot 10 real and virtual arrows from 18 m, whereas their HR, HRV, and breathing rate were measured, each lasting 4 min. Performance in VR and real archery was determined separately as the sum of the shots. We performed paired sample t‐tests to compare individuals’ performance, psychological, and psychophysiological responses recorded during VR and real arrow shooting. Afterward, we compared percentage changes between VR and real archery. Results Results showed that HR and root mean square of successive differences (RMMSD) were significantly higher during real archery compared to virtual archery. In addition, VR archery led to a greater percentage change in RMSSD compared to real archery. Participants reported greater RPE and perceived difficulty after real archery. Performance was also higher during VR archery than real archery. Conclusions Consequently, the results of the present study illustrated that VR, and real archery might lead to different autonomic response patterns in terms of vagal activity.

Introduction: Sudden Unexpected Death in Epilepsy (SUDEP) is the leading epilepsy-related cause of death, affecting approximately 1 per 1,000 individuals with epilepsy per year. Genetic variants that affect autonomic function, such as genes associated with cardiac arrhythmias, may predispose people with epilepsy to greater risk of both sudden cardiac death and SUDEP. Advances in next generation sequencing allow for the exploration of gene variants as potential biomarkers. Methods: Genetic testing for the presence of cardiac arrhythmia and epilepsy gene variants was performed via genetic panels in 39 cases of SUDEP identified via autopsy by the Ontario Forensic Pathology Service. Variants were summarized by in-silico evidence for pathogenicity from 4 algorithms (SIFT, PolyPhen-2, PROVEAN, Mutation Taster) and allele frequencies in the general population (GnomAD). A maximum credible population allele frequency of 0.00004 was calculated based on epilepsy prevalence and SUDEP incidence to assess whether a variant was compatible with a pathogenic interpretation. Results: Median age at the time of death was 33.3years (range: 2, 60). Fifty-nine percent (n=23) were male. Gene panels detected 62 unique variants in 45 genes: 19 on the arrhythmia panel and 26 on the epilepsy panel. At least one variant was identified in 28 (72%) of decedents. Missense mutations comprised 57 (92%) of the observed variants. At least three in silico models predicted 12 (46%) cardiac arrhythmia panel missense variants and 20 (65%) epilepsy panel missense variants were pathogenic. Population allele frequencies were <0.00004 for 11 (42%) of the cardiac variants and 10 (32%) of the epilepsy variants. Together, these metrics identified 13 SUDEP variants of interest. Discussion: Nearly three-quarters of decedents in this SUDEP cohort carried variants in comprehensive epilepsy or cardiac arrhythmia gene panels, with more than a third having variants in both panels. The proportion of decedents with cardiac variants aligns with recent studies of the disproportionate cardiac burden the epilepsy community faces compared to the general population and suggests a possible cardiac contribution to epilepsy mortality. These results identified 13 priority targets for future functional studies of these genes potential role in sudden death and demonstrates the necessity for further exploration of potential genetic contributions to SUDEP. [ABSTRACT FROM AUTHOR]

Background: Disordered autonomic nervous system regulation and supraspinal pain inhibition have been repeatedly described in chronic pain. We aimed to explore the effects of δ-9-tetrahydrocannabinol (THC), an emerging treatment option, on autonomic nervous system and central pain modulation measures in patients with chronic pain. Methods: Twelve male patients with chronic radicular neuropathic pain participated in a randomized, double-blind, crossover, placebo-controlled, single-administration trial. Low/high frequency (LF/HF) heart rate variability (HRV) ratio and conditioned pain modulation (CPM) response were measured and resting-state functional magnetic resonance imaging (MRI) was performed at baseline and after sublingual administration of either 0.2 mg/kg oral THC or placebo. Results: THC significantly reduced the LF/HF ratio compared with placebo (interaction effect F(1,11) = 20.5; p < 0.005) and significantly improved CPM responses (interaction effect F(1,9) = 5.2; p = 0.048). The THC-induced reduction in LF/HF ratio correlated with increased functional connectivity between the rostral ventrolateral medulla and the dorsolateral prefrontal cortex [T(10) = 6.4, cluster p-FDR < 0.005]. Conclusions: THC shifts the autonomic balance towards increased parasympathetic tone and improves inhibitory pain mechanisms in chronic pain. The increase in vagal tone correlates with connectivity changes in higher-order regulatory brain regions, suggesting THC exerts top-down effects. These changes may reflect a normalizing effect of THC on multiple domains of supraspinal pain dysregulation. Clinical Trial Registry Number: NCT02560545. [ABSTRACT FROM AUTHOR]

Neurocristopathies (NCPs) encompass a spectrum of disorders arising from issues during the formation and migration of neural crest cells (NCCs). NCCs undergo epithelial–mesenchymal transition (EMT) and upon key developmental gene deregulation, fetuses and neonates are prone to exhibit diverse manifestations depending on the affected area. These conditions are generally rare and often have a genetic basis, with many following Mendelian inheritance patterns, thus making them perfect candidates for precision medicine. Examples include cranial NCPs, like Goldenhar syndrome and Axenfeld–Rieger syndrome; cardiac–vagal NCPs, such as DiGeorge syndrome; truncal NCPs, like congenital central hypoventilation syndrome and Waardenburg syndrome; and enteric NCPs, such as Hirschsprung disease. Additionally, NCCs' migratory and differentiating nature makes their derivatives prone to tumors, with various cancer types categorized based on their NCC origin. Representative examples include schwannomas and pheochromocytomas. This review summarizes current knowledge of diseases arising from defects in NCCs' specification and highlights the potential of precision medicine to remedy a clinical phenotype by targeting the genotype, particularly important given that those affected are primarily infants and young children. [ABSTRACT FROM AUTHOR]

This article explores the use of infrared thermal imaging (ITI) as a non-invasive method to study parent-infant interactions. ITI can measure changes in cutaneous temperature and capture psychophysiological arousal states during social interactions. The authors discuss the potential of ITI to provide insight into autonomic co-regulation and bio-behavioral synchrony. They also highlight the challenges and considerations in conducting ITI studies. Additionally, the document provides a list of references and citations for scientific papers related to thermal facial imprints, autonomic contagion, mother-infant synchrony, and infant stress regulation. These papers discuss the physiological and developmental aspects of these phenomena and the potential applications of thermal imaging in studying emotions and deception detection. [Extracted from the article]

This document outlines ten evidence-based strategies for promoting heart and metabolic health and slowing down the aging process of the cardiovascular system. These strategies include engaging in regular exercise and calorie restriction to reduce waist circumference and increase muscle mass, following a minimally processed Mediterranean-like diet, practicing intermittent fasting and time-restricted feeding, being physically active every day, limiting alcohol consumption, not smoking, prioritizing quality sleep, reducing stress and engaging in cognitive stimulation, fostering friendships and compassion, and minimizing exposure to pollution while connecting with nature. By incorporating these strategies into their lifestyle, individuals can take proactive steps to support their cardiovascular health and prevent chronic diseases. [Extracted from the article]

Maintaining blood glucose at an appropriate physiological level requires precise coordination of multiple organs and tissues. The vagus nerve bidirectionally connects the central nervous system with peripheral organs crucial to glucose mobilization, nutrient storage, and food absorption, thereby presenting a key pathway for the central control of blood glucose levels. However, the precise mechanisms by which vagal populations that target discrete tissues participate in glucoregulation are much less clear. Here we review recent advances unraveling the cellular identity, neuroanatomical organization, and functional contributions of both vagal efferents and vagal afferents in the control of systemic glucose metabolism. We focus on their involvement in relaying glucoregulatory cues from the brain to peripheral tissues, particularly the pancreatic islet, and by sensing and transmitting incoming signals from ingested food to the brain. These recent findings - largely driven by advances in viral approaches, RNA sequencing, and cell-type selective manipulations and tracings - have begun to clarify the precise vagal neuron populations involved in the central coordination of glucose levels, and raise interesting new possibilities for the treatment of glucose metabolism disorders such as diabetes. [ABSTRACT FROM AUTHOR]

Survival requires the integration of external information and interoceptive cues to effectively guide advantageous behaviors, particularly foraging and other behaviors that promote energy acquisition and consumption. The vagus nerve acts as a critical relay between the abdominal viscera and the brain to convey metabolic signals. This review synthesizes recent findings from rodent models and humans revealing the impact of vagus nerve signaling from the gut on the control of higher-order neurocognitive domains, including anxiety, depression, reward motivation, and learning and memory. We propose a framework where meal consumption engages gastrointestinal tract-originating vagal afferent signaling that functions to alleviate anxiety and depressive-like states, while also promoting motivational and memory functions. These concurrent processes serve to favor the encoding of meal-relevant information into memory storage, thus facilitating future foraging behaviors. Modulation of these neurocognitive domains by vagal tone is also discussed in the context of pathological conditions, including the use of transcutaneous vagus nerve stimulation for the treatment of anxiety disorders, major depressive disorder, and dementia-associated memory impairments. Collectively, these findings highlight the contributions of gastrointestinal vagus nerve signaling to the regulation of neurocognitive processes that shape various adaptive behavioral responses. [ABSTRACT FROM AUTHOR]

The parasympathetic nervous system via the vagus nerve exerts profound influence over the heart. Together with the sympathetic nervous system, the parasympathetic nervous system is responsible for fine-tuned regulation of all aspects of cardiovascular function, including heart rate, rhythm, contractility, and blood pressure. In this review, we highlight vagal efferent and afferent innervation of the heart, with a focus on insights from comparative biology and advances in understanding the molecular and genetic diversity of vagal neurons, as well as interoception, parasympathetic dysfunction in heart disease, and the therapeutic potential of targeting the parasympathetic nervous system in cardiovascular disease. [ABSTRACT FROM AUTHOR]

Mobitz type II second-degree atrioventricular block (AVB) is an electrocardiographic pattern that describes what appears to be an all-or-none conduction without visible changes in the AV conduction time or PR intervals before and after a single non-conducted P wave. An unchanged PR interval after the block is a sine qua non of Mobitz type II block. A 2:1 AVB cannot be classified in terms of type I or type II AVB. The diagnosis of Mobitz type II block AVB requires a stable sinus rate, which is an important criterion because a vagal surge (generally benign) can cause simultaneous sinus slowing and AV nodal block, which can resemble Mobitz type II AVB. Atypical forms of Wenckebach AVB may be misinterpreted as Mobitz type II AVB when a series of PR intervals are constant before the block. Concealed His bundle or ventricular extrasystoles may mimic both Wenckebach and/or type II AVB (pseudo-AVB). Correctly identified Mobitz type II AVB is invariably at the level of the His–Purkinje system and is an indication for a pacemaker.

Studies have shown that Trait Emotional Awareness (TEA) – the ability to recognize one's emotions – and Heart Rate Variability (HRV) are both negatively associated with psychological disorders. Although these studies imply that TEA is related to HRV and may explain the association between HRV and psychological disorders, there is limited research investigating this implication. Such investigation is essential to illuminate the psychophysiological processes linked to psychological disorders. The present study aims to investigate a) the association between TEA and HRV, b) the association between HRV and psychological disorders, and c) whether TEA explains the association between HRV and psychological disorders. A sample of 41 German students completed self-report questionnaires as indicators of psychological disorders, including the Hospital Anxiety and Depression Scale (HADS; Snaith & Zigmond, 1983) for anxiousness and depressiveness, as well as the somatization scale of the Hopkins Symptom Checklist (HSCL; Derogatis et al., 1976) for physical complaints. HRV was measured at baseline (resting HRV) and during exposure to a fear-provoking movie clip (reactive HRV). As hypothesized, a) TEA showed a positive association with reactive HRV, b) HRV showed negative associations with anxiousness and physical complaints, and c) TEA explained the relationships between reactive HRV and anxiousness, as well as physical complaints. Contrary to our hypothesis, we did not find any association between HRV and depressiveness. We discussed the contribution of TEA to psychophysiological health, limited generalizability of the current study, and direct future research to explore the underlying mechanisms linking TEA to health.