Autonomic Nervous System Control Research Articles

The effect of a short breathing intervention on postural control and heart rate variability

AbstractPurposeThe objective of this study was to determine the immediate effect of a short breathing intervention on postural control and heart rate variability in healthy individuals.Materials/MethodsThe study involved 28 participants. Heart rate variability and heart rate were measured using a Polar (H10) sensor, and the sway path during posturography was recorded using the NeuroCom system, with participants standing on a firm then a foam surface in the eyes open and eyes closed conditions. All measurements were performed before and after the breathing intervention to provide baseline and post-intervention data. A short breathing intervention was performed between testing to stimulate the autonomic nervous system. In the Wilcoxon matched pairs comparison using Statistica software, P < 0.05 was considered statistically significant.ResultsThe breathing intervention caused a significant decrease in heart rate variability and an increase in heart rate. In the eyes closed condition, on a firm surface, the breathing intervention significantly reduced the sway path.ConclusionsThe breathing intervention reduced the sway path in conditions without visual information but appeared to have no effect on balance in conditions with visual information, suggesting that the postural function of the diaphragm becomes more prominent in nonvisual conditions. We obtained evidence of the relationship between the autonomic nervous system and postural control. The stimulation of the sympathetic tone by means of the breathing intervention had a significant effect on postural control on firm and foam surfaces without visual information and decreased postural sway.

Correlation between pupillary size and heart rate variability parameters among medical students

Autonomic nervous system controls and balances sympathetic and parasympathetic system to maintain homeostasis without conscious control. The sympathetic nervous system controls the dilation of the pupil or mydriasis. HR variation (HRV) analysis is a popular non-invasive tool for assessing functions of autonomic nervous system. Medical students are under constant cognitive load, it is required to follow-up on status on their autonomic control during their education phase. The objective of this study was to observe any correlation between pupillary size and heart rate.Total of 30 students participated in the study. Anthropometric measurements and vitals like pulse, blood pressure was recorded. Pupillary size of the participants was measured using the pupillometer in the illuminated. HRV recording was done by placing electrodes for standard Lead II ECG. HRV reports were generated using Kubios HRV 3.5 software standard version. The pupillary size Right and Left are negatively correlated with the SDNN, RMSSD, PNN50, HF, SDI and SD2. However, LF, LF/HF and SD2/SD1 ratio are positively correlated. These findings support the notion that pupillary size can serve as a non-invasive indicator of autonomic nervous system activity.

Autonomic nervous system and postural control regulation during orthostatic test as putative markers of physical resilience among community-dwelling older adults

IntroductionWe examined whether autonomic nervous system (ANS) and postural control regulation during orthostatic test reflect physical resilience by studying their associations with maximal walking speed and mortality. MethodsThe participants were community-dwelling Finnish men (n = 303) and women (n = 386) aged 75, 80, and 85 years at baseline. Systolic and diastolic blood pressure (BP), heart rate, heart rate variability (HRV), respiratory rate, and postural sway were obtained using a digital sphygmomanometer, a single-channel ECG, and thigh- and chest-worn accelerometers. Linear and Cox regression models were used to estimate the associations of the physiological indices with maximal 10-m walking speed and 5-year mortality separately for sexes. ResultsBetter maintenance of BP under orthostatic stress was associated with faster walking speed in women and lower mortality hazard in men. Greater HRV in terms of low frequency power and lower respiration rate in supine position and smaller orthostatic changes in these were associated with faster walking speed especially in women. Less postural sway after standing up was associated with faster walking speed in women (−0.057, SE 0.022, p = 0.011) and more postural sway with increased mortality hazard in men (HR 1.71, 95 % CI 1.20–2.43) even after controlling for BP responses. ConclusionsIn addition to ANS regulation at rest and under stress, adaptation of postural control system to orthostasis may be used in quantifying older adults' physical resilience. Wearable sensors capturing stimulus-response patterns and natural fluctuations of body functions may provide opportunities to monitor and incorporate different subsystems' resilience also in free-living conditions.

Heart Rate Variability as a Translational Dynamic Biomarker of Altered Autonomic Function in Health and Psychiatric Disease.

The autonomic nervous system (ANS) is responsible for the precise regulation of tissue functions and organs and, thus, is crucial for optimal stress reactivity, adaptive responses and health in basic and challenged states (survival). The fine-tuning of central ANS activity relies on the internal central autonomic regulation system of the central autonomic network (CAN), while the peripheral activity relies mainly on the two main and interdependent peripheral ANS tracts, the sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS). In disease, autonomic imbalance is associated with decreased dynamic adaptability and increased morbidity and mortality. Acute or prolonged autonomic dysregulation, as observed in stress-related disorders, affects CAN core centers, thereby altering downstream peripheral ANS function. One of the best established and most widely used non-invasive methods for the quantitative assessment of ANS activity is the computerized analysis of heart rate variability (HRV). HRV, which is determined by different methods from those used to determine the fluctuation of instantaneous heart rate (HR), has been used in many studies as a powerful index of autonomic (re)activity and an indicator of cardiac risk and ageing. Psychiatric patients regularly show altered autonomic function with increased HR, reduced HRV and blunted diurnal/circadian changes compared to the healthy state. The aim of this article is to provide basic knowledge on ANS function and (re)activity assessment and, thus, to support a much broader use of HRV as a valid, transdiagnostic and fully translational dynamic biomarker of stress system sensitivity and vulnerability to stress-related disorders in neuroscience research and clinical psychiatric practice. In particular, we review the functional levels of central and peripheral ANS control, the main neurobiophysiologic theoretical models (e.g., polyvagal theory, neurovisceral integration model), the precise autonomic influence on cardiac function and the definition and main aspects of HRV and its different measures (i.e., time, frequency and nonlinear domains). We also provide recommendations for the proper use of electrocardiogram recordings for HRV assessment in clinical and research settings and highlight pathophysiological, clinical and research implications for a better functional understanding of the neural and molecular mechanisms underlying healthy and malfunctioning brain-heart interactions in individual stress reactivity and psychiatric disorders.

Effects on heart rate from direct current block of the stimulated rat vagus nerve

Objective. Although electrical vagus nerve stimulation has been shown to augment parasympathetic control of the heart, the effects of electrical conduction block have been less rigorously characterized. Previous experiments have demonstrated that direct current (DC) nerve block can be applied safely and effectively in the autonomic system, but additional information about the system dynamics need to be characterized to successfully deploy DC nerve block to clinical practice. Approach. The dynamics of the heart rate (HR) from DC nerve block of the vagus nerve were measured by stimulating the vagus nerve to lower the HR, and then applying DC block to restore normal rate. DC block achieved rapid, complete block, as well as partial block at lower amplitudes. Main Results. Complete block was also achieved using lower amplitudes, but with a slower induction time. The time for DC to induce complete block was significantly predicted by the amplitude; specifically, the amplitude expressed as a percentage of the current required for a rapid, 60 s induction time. Recovery times after the cessation of DC block could occur both instantly, and after a significant delay. Both blocking duration and injected charge were significant in predicting the delay in recovery to normal conduction. Significance. While these data show that broad features such as induction and recovery can be described well by the DC parameters, more precise features of the HR, such as the exact path of the induction and recoveries, are still undefined. These findings show promise for control of the cardiac autonomic nervous system, with potential to expand to the sympathetic inputs as well.

Chapter 13 - Electrophysiological assessment of peripheral and central autonomic disorders

The autonomic nervous system (ANS) coordinates multiple reflex actions which are essential for life. The tests employed to evaluate the ANS provide valuable information of the functional state of these reflex arcs. The ideal test should be simple to perform, noninvasive, reproducible, sensitive, specific, safe, and appropriate for longitudinal studies. The availability of computer-based techniques has facilitated the electrophysiological assessment of ANS-mediated reflexes. The information provided by autonomic testing must be analyzed in combination with the clinical history and physical examination of the patient, allowing for a hypothesis that can be tested. Properly performed and interpreted, ANS testing can be used to confirm the presence of an ANS disturbance and the involved functional pathways, as well as the extent, intensity, and site of injury. This chapter describes the most important electrophysiological tests used to evaluate the ANS control of cardiovascular reflexes and sweat gland activity.

Relationship between Body Composition and Cardiac Autonomic Regulation in a Large Population of Italian Olympic Athletes.

Athletic performance is determined by many factors, such as cardiorespiratory fitness, muscular strength and psychological features, which all interact simultaneously. The large Italian National Olympic Committee database of Olympic athletes offers a unique healthy population to verify the strength of the interplay among a number of major elements of training, including autonomic nervous system (ANS) modulation, biochemical indicators and body composition, in a system medicine approach. This observational, retrospective study involved 583 individuals. As part of the yearly precompetitive examination, cardiac autonomic (heart rate variability), psychological, physical (cycloergometer stress test), biochemical and body composition (BOD POD) evaluations were performed. In subsequent analysis, we first considered the relationship between body composition and single individual variables in a simple correlation matrix, including a multitude of variables; then, Exploratory Factor Analysis (EFA) restricted the information to six latent domains, each combining congruent information in relation to body composition. Finally, we employed a multiple quantile regression model to evaluate possible relationships between ANSIs (index capable of synthetizing ANS regulation) and the latent domains indicated by EFA reflecting body composition. We observed a clear relationship between ANS and body mass composition parameters, as indicated by both bivariate correlations and the quantile regression result of ANSIs versus the latent domain aggregating mainly body composition data expressed in % (p = 0.002). In conclusion, these results suggest that specific training may elicit parallel adaptation of ANS control and body composition. The analysis of Olympic athletes’ data allowed us to obtain a better understanding of the complex, multidimensional factors involved in determining sport performance. The latter appears to be determined by the simultaneous interaction not only of cardiorespiratory fitness, muscular strength and psychological features, but also of ANS cardiovascular modulation and body composition.

Progressive Additive Benefits of Prehabilitation and Subsequent Bariatric Surgery on Cardiac Autonomic Regulation as Assessed by Means of a Simple Unitary Composite Index: Preliminary Data from an Observational Study.

Obesity is associated with an increased risk of several chronic comorbidities, which may also be determined by dysfunctional autonomic nervous system (ANS). The influence of bariatric surgery (BS) on ANS balance was explored in previous studies, but with high heterogeneity in both the assessment timing and methods employed. In the present observational study, we applied a clinical protocol which considers two subsequent phases. Twenty-nine non-diabetic obese subjects were studied at baseline (T0), after one month of lifestyle modification (prehabilitation) (phase 1-T1), and after eight months following BS (phase 2-T2). ANS regulation was assessed across the three study epochs by means of ANSI, a single composite percent-ranked proxy of autonomic balance, being free of gender and age bias, economical and simple to apply in a clinical setting. The aim of the present study was to investigate the effects of the clinical protocol based on prehabilitation and subsequent BS on the ANS regulation by means of ANSI. Potential intertwined correlations with metabolic parameters were also investigated. Notably, we observed a progressive improvement in ANS control, even by employing ANSI. Moreover, the reduction in the markers of sympathetic overactivity was found to significantly correlate with the amelioration in some metabolic parameters (fasting glucose, insulin levels, and waist circumference), as well as in stress and tiredness perception. In conclusion, this study provides convincing evidence that a unitary proxy of cardiac autonomic regulation (CAR) may reflect the progressive improvement in autonomic regulation following behavioral and surgical interventions in obese patients. Intriguingly, this might contribute to reducing cardiovascular and metabolic risk.

Sex differences in autonomic responses to stress: implications for cardiometabolic physiology.

Chronic stress is a significant risk factor for negative health outcomes. Furthermore, imbalance of autonomic nervous system control leads to dysregulation of physiological responses to stress and contributes to the pathogenesis of cardiometabolic and psychiatric disorders. However, research on autonomic stress responses has historically focused on males, despite evidence that females are disproportionality affected by stress-related disorders. Accordingly, this mini-review focuses on the influence of biological sex on autonomic responses to stress in humans and rodent models. The reviewed literature points to sex differences in the consequences of chronic stress, including cardiovascular and metabolic disease. We also explore basic rodent studies of sex-specific autonomic responses to stress with a focus on sex hormones and hypothalamic-pituitary-adrenal axis regulation of cardiovascular and metabolic physiology. Ultimately, emerging evidence of sex differences in autonomic-endocrine integration highlights the importance of sex-specific studies to understand and treat cardiometabolic dysfunction.

Eastern equine encephalitis virus rapidly infects and disseminates in the brain and spinal cord of cynomolgus macaques following aerosol challenge.

Eastern equine encephalitis virus (EEEV) is mosquito-borne virus that produces fatal encephalitis in humans. We recently conducted a first of its kind study to investigate EEEV clinical disease course following aerosol challenge in a cynomolgus macaque model utilizing the state-of-the-art telemetry to measure critical physiological parameters. Here, we report the results of a comprehensive pathology study of NHP tissues collected at euthanasia to gain insights into EEEV pathogenesis. Viral RNA and proteins as well as microscopic lesions were absent in the visceral organs. In contrast, viral RNA and proteins were readily detected throughout the brain including autonomic nervous system (ANS) control centers and spinal cord. However, despite presence of viral RNA and proteins, majority of the brain and spinal cord tissues exhibited minimal or no microscopic lesions. The virus tropism was restricted primarily to neurons, and virus particles (~61-68 nm) were present within axons of neurons and throughout the extracellular spaces. However, active virus replication was absent or minimal in majority of the brain and was limited to regions proximal to the olfactory tract. These data suggest that EEEV initially replicates in/near the olfactory bulb following aerosol challenge and is rapidly transported to distal regions of the brain by exploiting the neuronal axonal transport system to facilitate neuron-to-neuron spread. Once within the brain, the virus gains access to the ANS control centers likely leading to disruption and/or dysregulation of critical physiological parameters to produce severe disease. Moreover, the absence of microscopic lesions strongly suggests that the underlying mechanism of EEEV pathogenesis is due to neuronal dysfunction rather than neuronal death. This study is the first comprehensive investigation into EEEV pathology in a NHP model and will provide significant insights into the evaluation of countermeasure.

Influence of Spontaneous and Mechanical Ventilation on Frequency-Based Measures of Heart Rate Variability.

Frequency-based measures of heart rate variability have been shown to be a useful physiological marker in both clinical and research settings providing insight into the functioning of the autonomic nervous system. Ongoing interactions between the autonomic nervous system control of the heart and lung occurs during each ventilation cycle because of their anatomical position within the closed thoracic cavity. Mechanical ventilation and subsequent removal change the normal ventilator mechanics producing alterations in the tidal volume, intrathoracic pressure, and oxygen delivery. A noninvasive method called heart rate variability (HRV) can be used to evaluate this interaction during ventilation and can be quantified by applying frequency-based measures of the variability between heartbeats. Although HRV is a reliable method to measure alteration of the autonomic nervous system (ANS) function and cardiopulmonary interaction, there have been limited reports concerning the changes in the frequency-based measure of HRV during both spontaneous and mechanical ventilation. The purpose of this methodological study is therefore to describe the physiological influence of both spontaneous and mechanical ventilation on frequency-based measures of HRV.

Neuronal Induction of Bone-Fat Imbalance through Osteocyte Neuropeptide Y.

A differentiation switch of bone marrow mesenchymal stem/stromal cells (BMSCs) from osteoblasts to adipocytes contributes to age‐ and menopause‐associated bone loss and marrow adiposity. Here it is found that osteocytes, the most abundant bone cells, promote adipogenesis and inhibit osteogenesis of BMSCs by secreting neuropeptide Y (NPY), whose expression increases with aging and osteoporosis. Deletion of NPY in osteocytes generates a high bone mass phenotype, and attenuates aging‐ and ovariectomy (OVX)‐induced bone‐fat imbalance in mice. Osteocyte NPY production is under the control of autonomic nervous system (ANS) and osteocyte NPY deletion blocks the ANS‐induced regulation of BMSC fate and bone‐fat balance. γ‐Oryzanol, a clinically used ANS regulator, significantly increases bone formation and reverses aging‐ and OVX‐induced osteocyte NPY overproduction and marrow adiposity in control mice, but not in mice lacking osteocyte NPY. The study suggests a new mode of neuronal control of bone metabolism through the ANS‐induced regulation of osteocyte NPY.

Effect of aerobic exercise on executive function in individuals with methamphetamine use disorder: Modulation by the autonomic nervous system

This study assessed the effects of aerobic exercise on cardiac autonomic nervous system function (based on heart rate variability [HRV]) and executive function among individuals with methamphetamine use disorder (MUD). We further examine the role of autonomic nervous system control in aerobic exercise (assessed via cardiopulmonary fitness) and executive function. A total of 330 individuals with MUD were randomly divided into exercise (n = 165) and control (n = 165) groups, who underwent eight-week aerobic exercise/health education program consisting of five 60 min sessions a week. The outcome measures included cardiopulmonary fitness, HRV time-domain and frequency-domain parameters, and executive function. Our statistical analyses comprised repeated-measures analyses of variance, correlation analyses, and mediation and moderation effect tests. The results indicated that aerobic exercise could simultaneously improve autonomic nervous system function and executive function among individuals with MUD. Moreover, the changes in cardiopulmonary fitness, high frequency HRV, and executive function were positively correlated. HRV did not significantly mediate the relationship between aerobic exercise and executive function; however, it did have a moderating effect, which was eliminated after adjusting for demographic and drug-use covariates. Among the covariates, age was the greatest confounder and was inversely proportional to cardiopulmonary function, HRV, and executive function. Cardiac autonomic nervous system function exerted a moderating, rather than a mediating, effect on the relationship between aerobic exercise and executive function. However, this potential effect was largely influenced by covariates, particularly age.

P–073 High-intensity interval training modulates the effects of hypertension on inflammatory mediators in testis in adult spontaneously hypertensive rats

Abstract Study question Is the high-intensity interval training (HIIT) able to prevent the increase of the inflammatory proteins in the testis of spontaneously hypertensive rats (SHR)? Summary answer HIIT for 8 weeks inhibits the increase of the tumor necrosis factor alpha (TNFα) and the interleukin 6 (IL6) in the testis of SHR. What is known already Hypertension increases the inflammatory cytokines of the cardiovascular system, causing damage in the microcirculation and in the testes. Hypertension is a cause of low fertility in men and exercises are indicated to decrease blood pressure and improve overall health. HIIT is characterized by short periods of exercise, with an intensity equal to or greater than the anaerobic threshold, separated by recovery periods. HIIT can be indicated for cardiac patients, as this type of training improves the cardiac autonomic nervous system and lipemic control in both hypertensive and normotensive individuals. Study design, size, duration Male Wistar-Kyoto rats without hypertension and SHRs were divided into 3 groups (n = 4): WKY (Wistar-Kyoto); SHR; and SHR-HIIT (SHRs that performed HIIT). The HIIT was realized in treadmill for 5 days/week for 8 weeks. HIIT started with 5 times of 4 minutes of 100% of the maximum exhaust speed, with active rest intervals of 3 minutes at 60%. There was an increase of once every week until reaching 7 times each session. Participants/materials, setting, methods Samples from testicles were used for immunostainig IL6 and TNFα. After the blocking, the sections were subjected to reaction of specific antibodies IL6 (1:50, E–4, sc–28343) and TNFα (1:50, 52B83, sc–257) at 4ºC overnight, and with secondary antibodies m-IgGK (1:200, IgG-HRP, sc–516) at room temperature for 2 hours. Diaminobenzidine (1:50) was used against Harris stained with Hematoxylin and evaluated in the photomicroscope. Data were analyzed by One-Way ANOVA followed by Tukey post test (P < 0.05). Main results and the role of chance The immunostainig of IL6 was higher in SHR (10.23 ± 0.47) than in SHR-HIIT (8.69 ± .44) group (P = 0,0237). From the same perspective, immunoexpression of TNFα was higher in SHR (10.10 ± 0.42) than WKY (8.24 ± 0.24) and SHR-HIIT (7.82 ± 0.39) groups (P = 0.0018). Limitations, reasons for caution As a limitation of the study, we have no measurement of fertility parameters to affirm that the HIIT improve the fertility because of the reduction of inflammatory mediators. Wider implications of the findings: The hypertension drugs have a negative effect on fertility. HIIT can be suggested as a treatment for hypertension as an alternative to medication, since HIIT can inhibit the increase of the inflammatory mediators in testis and its consequences to the reproduction. Financial support by São Paulo Research foundation, FAPESP (2018/22682–0). Trial registration number 2018/22682–0

Assessing and Comparing Multiple Metrics of Heart Rate Variability to Measure Cardiac Parasympathetic and Sympathetic Tone – Does the Math Miss a Beat?

The relative contributions of parasympathetic and sympathetic autonomic nervous system control of cardiac activity is often assessed through non-invasive heart rate variability (HRV) metrics. There are various HRV metrics utilized to measure cardiac autonomic balance. However, the relationship between HRV metrics and cardiac autonomic tone is understudied and controversial. We assessed the internal consistency of using three specific HRV metrics of cardiac autonomic balance at rest using electrocardiography (ECG) in a larger number of healthy participants: time domain, frequency domain and Poincaré plots. Data was analyzed from a large set (n=136) of archived files from previous studies, where a 5-min segment of resting baseline ECG was previously-recorded in young, healthy men and women (ADInstruments, LabChart HRV module, v8). The three specific HRV metrics quantified from the ECG baseline were time domain (SDRR and RMSSD; ms), frequency domain (LF, HF, LF/HF; n.u.) and Poincaré plots (SD1, SD2, SD1/SD2; ms). The HRV metrics considered to be associated with cardiac parasympathetic activity are RMSSD, HF and SD1, whereas SDRR, LF and SD2 are considered to be associated with mixed cardiac parasympathetic and sympathetic activity (i.e., sympathetic influence). We correlated the three parasympathetic HVR metrics (RMSSD, HF and SD1), within-individual. We also correlated the three mixed cardiac autonomic metrics (SDRR, LF and SD2), within-individual. Regarding the three parasympathetic metrics, (a) RMSSD and SD1 were strongly, positively and significantly-correlated (r=1.0, P<0.0001), suggesting similar mathematical calculations for each and (b) both RMSSD and HF, and SD1 and HF were moderately, positively and significantly-correlated (both, rs=0.41, P<0.00001). Regarding mixed parasympathetic and sympathetic metrics, (a) SDRR and SD2 were strongly, positively and significantly-correlated (r=0.96, P<0.0001), suggesting similar mathematical calculations for each, (b) SDRR and LF were not significantly-correlated (rs=-0.1, P=0.25) and (c) SD2 and LF were no significantly correlated (rs=0.01, P=0.9). Our analysis on a large data set suggests high agreement and internal consistency between parasympathetic cardiac metrics, within-individual. However, on metrics with mixed parasympathetic and sympathetic influence, HRV metrics lacked agreement and internal consistently. These data suggest that (a) any of the three parasympathetic metrics are likely useful in assessing cardiac parasympathetic tone, but that (b) caution should be used in interpreting HRV metrics typically utilized in assessing cardiac sympathetic tone.

Signaling and function of cardiac autonomic nervous system receptors: Insights from the GPCR signalling universe.

The two branches of the autonomic nervous system (ANS), adrenergic and cholinergic, exert a multitude of effects on the human myocardium thanks to the activation of distinct G protein-coupled receptors (GPCRs) expressed on the plasma membranes of cardiac myocytes, cardiac fibroblasts, and coronary vascular endothelial cells. Norepinephrine (NE)/epinephrine (Epi) and acetylcholine (ACh) are released from cardiac ANS terminals and mediate the biological actions of the ANS on the heart via stimulation of cardiac adrenergic or muscarinic receptors, respectively. In addition, several other neurotransmitters/hormones act as facilitators of ANS neurotransmission in the heart, taking part in the so-called nonadrenergic noncholinergic (NANC) part of the ANS's control of cardiac function. These NANC mediators also use several different cell membrane-residing GPCRs to exert their effects in the myocardium. Cardiac ANS dysfunction and an imbalance between the activities of its two branches underlie a variety of cardiovascular diseases, from heart failure and hypertension to coronary artery disease, myocardial ischemia, and arrhythmias. In this review, we present the main well-established signaling modalities used by cardiac autonomic GPCRs, including receptors for salient NANC mediators, and we also highlight the latest developments pertaining to cardiac cell type-specific signal transduction, resulting in cell type-specific cardiac effects of each of these autonomic receptors.

How everyday sounds can trigger strong emotions: ASMR, misophonia and the feeling of wellbeing.

We propose that synesthetic cross-activation between the primary auditory cortex and the anatomically adjacent insula may help explain two puzzling conditions-autonomous sensory meridian response (ASMR) and misophonia-in which quotidian sounds involuntarily trigger strong emotional responses. In ASMR the sounds engender relaxation, while in misophonia they trigger an aversive response. The insula both plays an important role in autonomic nervous system control and integrates multiple interoceptive maps representing the physiological state of the body to substantiate a dynamic representation of emotional wellbeing. We propose that in ASMR cross-activation of the map for affective (sensual) touch leads to an increase in subjective wellbeing and parasympathetic activity. Conversely, in misophonia the effect of the cross-activation is to decrease emotional wellbeing and increase sympathetic activity. Our hypothesis also illuminates the connection between hearing and wellbeing more broadly and helps explain why so many people experience decreased wellbeing from modern urban soundscapes.

Effect of psychosocial factors and heart ate variability on blood pressure control in patient with primary hypertension:A path analysis

Abstract Background Hypertension (HTN) is one of the major factors driving the global burden of cardiovascular diseases. About 40% of the adults are affected by elevated blood pressure around the world. The etiology of HTN is multifactorial, including psychological distress, especially symptoms of anxiety and depression. A few meta-analyses and longitudinal studies have reported an association between symptoms of anxiety, depression and HTN. Social support is an important factor in the regulation of emotions in HTN patients. The autonomic nervous system (ANS) plays an important role in the homeostatic control of the cardiovascular system. The measurement of heart rate variability (HRV) is used to evaluate ANS regulation in clinical research.The HRV is also a predictor of cardiovascular-cause events and mortality. Previous studies have identified the association of cardiovascular diseases with social support, anxiety, and depression. Some recent studies have also evaluated the relationship between HRV and cardiovascular diseases. However, very few studies have investigated the association of psychosocial factors, HRV, and blood pressure in patients with HTN. Purpose The purpose of this study was to evaluate the effect of psychosocial factors including social support, symptoms of anxiety/depressive, and heart rate variability on mean arterial blood pressures in patients with primary hypertension. Methods A cross-sectional descriptive and correlative study was performed. Participants were recruited by convenience sampling from the Cardiovascular Outpatient Clinic at a Medical Center. Data were collected using structured questionnaires, including the Social Support and Hospital Anxiety and Depression Scales. While heart rate variability was measured by a handheld limb lead electrocardiogram recorder device, blood pressure was measured by an automatic sphygmomanometer. Data were analyzed by the structural equation path analysis by the IBM SPSS Amos 21.0 statistical software packages. Results This study included 301 patients with primary hypertension. The scores of the Social Support Scale had a significantly direct effect on the scores of Hospital Anxiety and Depression Scale. The Hospital Anxiety and Depression Scale scores had a significantly direct effect on the heart rate variability. The low frequency/ high-frequency ratio of heart rate variability had a significantly direct effect on the mean arterial blood pressures. The path model including all variables explained 45% variance in the mean arterial blood pressures and had good fit indices. Conclusion Findings from our research highlight the significance of how psychosocial factors can affect the autonomic nervous system and blood pressure control of patients with primary hypertension. These findings can aid in developing an intervention program for blood pressure management in future. Funding Acknowledgement Type of funding source: None

Classifying Affective Haptic Stimuli through Gender-Specific Heart Rate Variability Nonlinear Analysis

This study reports on how velocity and force levels of caress-like haptic stimuli can elicit different emotional responses, which can be identified through the analysis of Autonomic Nervous System (ANS) dynamics. Affective stimuli were administered on the forearm of 32 healthy volunteers (16 women) through a haptic device with two levels of force, 2 N and 6 N, and two levels of velocity, 9.4 mm/s and 37 mm/s. ANS dynamics was estimated through Heart Rate Variability (HRV) linear and nonlinear analysis on recordings gathered before and after each stimulus. To this extent, we here propose and assess novel features from HRV symbolic analysis and Lagged Poincaré Plot. Classification was performed following a leave-one-subject-out procedure on nonlinear support vector machines. Pattern classification was split according to gender, significantly improving accuracies of recognition with respect to a “all-subjects” classification. Caressing force and velocity levels were recognized with up to 80 percent accuracy for men, and up to 84.38 percent for women. Our results demonstrate that changes in ANS control on cardiovascular dynamics, following emotional changes induced by caress-like haptic stimuli, can be effectively recognized by the proposed computational approach, considering that they occur in a gender-specific and nonlinear manner.

Processing speed and attention training modifies autonomic flexibility: A mechanistic intervention study

Adaptation capacity is critical for maintaining cognition, yet it is understudied in groups at risk for dementia. Autonomic nervous system (ANS) is critical for neurovisceral integration and is a key contributor to adaptation capacity. To determine the central nervous system’s top-down regulation of ANS, we conducted a mechanistic randomized controlled trial study, using a 6-week processing speed and attention (PS/A)-targeted intervention. Eighty-four older adults with amnestic mild cognitive impairment (aMCI) were randomized to a 6-week PS/A-targeted intervention or an active control without PS/A. Utilizing repeated measures (i.e., PS/A test different from the intervention, resting and cognitive task-based ECG, and resting fMRI) at baseline, immediately post-intervention (post-test), and 6-month follow-up, we aimed to test whether PS/A causally influences vagal control of ANS via their shared central neural pathways in aMCI. We indexed vagal control of ANS using high-frequency heart rate variability (HF-HRV) extracted from ECG data. Functional brain connectivity patterns were extracted from fMRI using advanced statistical tools. Compared to the control group, the intervention group showed significant improvement in PS/A, HF-HRV, salience network (SN), central executive network (CEN), and frontal parietal network (FPN) connectivity at post-test; the effect on SN, CEN, and FPN remained at 6-month follow-up. Changes in PS/A and SN connectivity significantly predicted change in HF-HRV from baseline to post-test and/or 6-month-follow-up. Age, neurodegeneration, nor sex did not affect these relationships. This work provides novel support for top-down regulation of PS/A and associated SN on vagal control of ANS. Intervening PS/A may be a viable approach for promoting adaptation capacity in groups at risk for dementia.