Autonomic Nervous System Responses Research Articles

Heart rate variability in horses with and without severe equine asthma.

Equine asthma in severe form (severe equine asthma [sEA]) shares remarkable similarities with human asthma. Human studies detected changes in the autonomic nervous system function in asthmatic patients based on heart rate variability (HRV) analysis. Observational study. To investigate the relationship between sEA and HRV in horses. Twenty horses diagnosed with sEA and 20 asymptomatic (non-sEA) horses were investigated. SEA horses showed clinical signs. The RR intervals of the ECG were recorded for 1 h at rest between 9 AM and 11 AM using a heart rate (HR) monitor. HRV data were calculated using Kubios software. Parameters recorded for the sEA and non-sEA groups were compared using one-way MANOVA model. The significance level was set at α = 0.05. SD2 (mean 99.6 ± SD 25.3 vs. 42.5 ± 17.1), SDNN (82.7 ± 20.7 vs. 41.3 ± 14.3), TINN (398.1 ± 104.9 vs. 209.3 ± 71.9), SD2/SD1 ratio (1.7 ± 0.2 vs. 1.1 ± 0.3), Total power (4740.2 ± 1977.9 vs. 1503.0 ± 1179.3), LF (2415.3 ± 1072.4 vs. 707.4 ± 649.9), SD1 (60.9 ± 15.9 vs. 39.2 ± 14.1), RMSSD (86.0 ± 22.6 vs. 55.3 ± 19.8) and HF (1575.8 ± 902.5 vs. 578.1 ± 491.1) were lower in sEA horses compared with the non-sEA horses (p < 0.01 for each variable). SD2, SDNN, TNN, the SD2/SD1 ratio and Total power showed the greatest discriminatory power in differentiating the sEA and non-sEA groups. Small sample size. Our findings indicate that like humans, asthmatic horses show an overall reduction in autonomic control. A relative increase of the parasympathetic modulation of the heart was also observed. After further investigations, HRV measurement might be a non-invasive approach to monitor autonomic nervous system responses of sEA horses.

Orthostatic testing for heart rate and heart rate variability monitoring in exercise science and practice.

Orthostatic testing, involving the transition from different body positions (e.g., from lying or sitting position to an upright or standing position), offers valuable insights into the autonomic nervous system (ANS) functioning and cardiovascular regulation reflected through complex adjustments in, e.g., measures of heart rate (HR) and heart rate variability (HRV). This narrative review explores the intricate physiological mechanisms underlying orthostatic stress responses and evaluates its significance for exercise science and sports practice. Into this matter, active orthostatic testing (e.g., active standing up) challenges the cardiovascular autonomic function in a different way than a passive tilt test. It is well documented that there is a transient reduction in blood pressure while standing up, leading to a reflex increase in HR and peripheral vasoconstriction. After that acute response systolic and diastolic blood pressures are usually slightly increased compared to supine lying body position. The ANS response to standing is initiated by instantaneous cardiac vagal withdrawal, followed by sympathetic activation and vagal reactivation over the first 25-30 heartbeats. Thus, HR increases immediately upon standing, peaking after 15-20 beats, and is less marked during passive tilting due to the lack of muscular activity. Standing also decreases vagally related HRV indices compared to the supine position. In overtrained endurance athletes, both parasympathetic and sympathetic activity are attenuated in supine and standing positions. Their response to standing is lower than in non-overtrained athletes, with a tendency for further decreased HRV as a sign of pronounced vagal withdrawal and, in some cases, decreased sympathetic excitability, indicating a potential overtraining state. However, as a significant main characteristic, it could be noted that additional pathophysiological conditions consist in a reduced responsiveness or counter-regulation of neural drive in ANS according to an excitatory stimulus, such as an orthostatic challenge. Hence, especially active orthostatic testing could provide additional information about HR(V) reactivity and recovery giving valuable insights into athletes' training status, fatigue levels, and adaptability to workload. Measuring while standing might also counteract the issue of parasympathetic saturation as a common phenomenon especially in well-trained endurance athletes. Data interpretation should be made within intra-individual data history in trend analysis accounting for inter-individual variations in acute responses during testing due to life and physical training stressors. Therefore, additional measures (e.g., psychometrical scales) are required to provide context for HR and HRV analysis interpretation. However, incidence of orthostatic intolerance should be evaluated on an individual level and must be taken into account when considering to implement orthostatic testing in specific subpopulations. Recommendations for standardized testing procedures and interpretation guidelines are developed with the overall aim of enhancing training and recovery strategies. Despite promising study findings in the above-mentioned applied fields, further research, thorough method comparison studies, and systematic reviews are needed to assess the overall perspective of orthostatic testing for training monitoring and fine-tuning of different populations in exercise science and training.

Pupillometry and autonomic nervous system responses to cognitive load and false feedback: an unsupervised machine learning approach.

Pupil dilation is controlled both by sympathetic and parasympathetic nervous system branches. We hypothesized that the dynamic of pupil size changes under cognitive load with additional false feedback can predict individual behavior along with heart rate variability (HRV) patterns and eye movements reflecting specific adaptability to cognitive stress. To test this, we employed an unsupervised machine learning approach to recognize groups of individuals distinguished by pupil dilation dynamics and then compared their autonomic nervous system (ANS) responses along with time, performance, and self-esteem indicators in cognitive tasks. Cohort of 70 participants were exposed to tasks with increasing cognitive load and deception, with measurements of pupillary dynamics, HRV, eye movements, and cognitive performance and behavioral data. Utilizing machine learning k-means clustering algorithm, pupillometry data were segmented to distinct responses to increasing cognitive load and deceit. Further analysis compared clusters, focusing on how physiological (HRV, eye movements) and cognitive metrics (time, mistakes, self-esteem) varied across two clusters of different pupillary response patterns, investigating the relationship between pupil dynamics and autonomic reactions. Cluster analysis of pupillometry data identified two distinct groups with statistically significant varying physiological and behavioral responses. Cluster 0 showed elevated HRV, alongside larger initial pupil sizes. Cluster 1 participants presented lower HRV but demonstrated increased and pronounced oculomotor activity. Behavioral differences included reporting more errors and lower self-esteem in Cluster 0, and faster response times with more precise reactions to deception demonstrated by Cluster 1. Lifestyle variations such as smoking habits and differences in Epworth Sleepiness Scale scores were significant between the clusters. The differentiation in pupillary dynamics and related metrics between the clusters underlines the complex interplay between autonomic regulation, cognitive load, and behavioral responses to cognitive load and deceptive feedback. These findings underscore the potential of pupillometry combined with machine learning in identifying individual differences in stress resilience and cognitive performance. Our research on pupillary dynamics and ANS patterns can lead to the development of remote diagnostic tools for real-time cognitive stress monitoring and performance optimization, applicable in clinical, educational, and occupational settings.

Effect of classical music on light-plane anaesthesia and analgesia in dogs subjected to surgical nociceptive stimuli

The objectives of this prospective, randomized, blinded, crossover, experimental study were to detect the potential anaesthetic- and analgesic-sparing effects of classical music provided to dogs undergoing skin surgery, and to investigate the role of substance P as an intraoperative pain indicator. Twenty dogs were included, each subjected to three different treatments: Chopin music, Mozart music and no music. They were premedicated with acepromazine, butorphanol and meloxicam and anaesthetized with propofol and isoflurane. Fentanyl was used as rescue analgesia. The anaesthetic depth was monitored by using the bispectral index along with standard anaesthetic monitoring, and autonomic nervous system responses were used to monitor the adequacy of analgesia. Furthermore, measurements of substance P serum concentration were carried out. Dogs exposed to music required less isoflurane and fentanyl. Furthermore, a statistically significant effect of time on substance P concentration was observed regardless of exposure to music, and there was a significant interaction effect between different timepoints and the type of acoustic stimulus. Classical music seems to have an isoflurane and fentanyl sparing effect on dogs undergoing minor surgery. Following surgical stimulation, the serum substance P concentration increases rapidly, and thus appears to be a potentially useful pain indicator.

Exploring the Relationship Between Voice Disorders in Indian Classical Music and the Guru-Shishya Parampara Through an Understanding of the Autonomic Nervous System

ABSTRACT The Guru-Shishya Parampara (GSP), translated as the teacher-student tradition, is a lineage-based oral tradition in Indian Classical Music (ICM). This study explores the relationship between GSP’s traditional obedience-authority dynamic and prevalent voice disorders experienced by ICM practitioners. Combining Constructivist Grounded Theory document analysis and a narrative literature review, the research investigates how disciplinarian tendencies and power differentials in authoritarian implementations of the GSP may contribute to or reinforce voice disorders resulting from psychological strain. Adopting the Indigenous Research Paradigm, the study prioritizes insights from ICM practitioners’ lived experiences within the cultural context of ICM within the analysis. A narrative review of existing literature on the links between autonomic nervous system responses associated with psychological stressors and voice disorders is discussed to further understand the impact of authoritarian GSPs on singers’ voices. Literature on compassion is additionally explored to discuss potential solutions to address the identified issues. Through this approach, the study offers insights into the complex interactions between power dynamics, psychological strain, and voice disorders within obedience-expectant GSPs, aiming to contribute to the development of effective interventions, highlighting that which already exists within ICM culture, to promote vocal health and overall well-being in this ancient and culturally significant tradition.

Heart Rate Variability in Military Pilots During Flight: A Scoping Review.

Piloting an aircraft is a complex multitasking activity that involves managing information in a nonautomatic way and generates a high workload (psychological, cognitive, and physical) for the pilot. The excess of these demands can result in decreased performance and may impair flight safety. Heart rate variability (HRV) has been used in recent studies as a method to investigate operator's workload in complex environments. This measure can assess the stress and recovery ability of the autonomic nervous system. However, a better understanding of flight influence on the pilot's autonomic modulation is necessary. Therefore, this scoping review aims to systematically map the studies related to changes in the autonomic modulation in military pilots during flight, in order to characterize their workload at different times and flight profiles. A literature search was conducted using MEDLINE (by PubMed), SCOPUS, and LILACS databases. Recent records (2002-2022) that analyzed HRV in military pilots during flight were included. Meanwhile, studies in which piloting activity was not performed were excluded. The study was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline extension for Scoping Reviews and the Updated Methodological Guidance for the Conduct of Scoping Reviews. A total of 298 records were obtained, of which 19 were included in the scoping review. The studies analyzed flights performed in high- and low-performance aircrafts, helicopters, and flight simulators, using time domain, frequency domain, and nonlinear HRV indices. Real and simulated flights produced significant autonomic changes. Some flights elicited autonomic nervous system responses that persisted up to 5 h after landing. During real flight, the most sensitive indices for identifying variations in pilot workload were root mean square of successive differences between normal heartbeats, standard deviation of interbeat interval of normal sinus beat (SDNN), ratio of low-frequency to high-frequency power, and Poincaré plot standard deviation perpendicular to the line of identity (SD1), whereas the interbeat interval (RR), SDNN, SD1, and Poincaré plot standard deviation along the line of identity (SD2) were the most sensitive indices when comparing segments of simulated flight with different levels of difficulty. This scoping review provided insight into the influence of flight on autonomic modulation in military pilots. Some key themes were highlighted: Increased sympathetic activity during flight, sensibility of different domains of HRV to flight demands, and autonomic changes during recovery time. Future research efforts may allow us to enhance the understanding of pilot's workload limits and to elucidate the optimal postflight recovery time.

Pupil contagion variation with gaze, arousal, and autistic traits

Pupillary contagion occurs when one’s pupil size unconsciously adapts to the pupil size of an observed individual and is presumed to reflect the transfer of arousal. Importantly, when estimating pupil contagion, low level stimuli properties need to be controlled for, to ensure that observations of pupillary changes are due to internal change in arousal rather than the external differences between stimuli. Here, naturalistic images of children’s faces depicting either small or large pupils were presented to a group of children and adolescents with a wide range of autistic traits, a third of whom had been diagnosed with autism. We examined the extent to which pupillary contagion reflects autonomic nervous system reaction through pupil size change, heart rate and skin conductance response. Our second aim was to determine the association between arousal reaction to stimuli and degree of autistic traits. Results show that pupil contagion and concomitant heart rate change, but not skin conductance change, was evident when gaze was restricted to the eye region of face stimuli. A positive association was also observed between pupillary contagion and autistic traits when participants’ gaze was constrained to the eye region. Findings add to a broader understanding of the mechanisms underlying pupillary contagion and its association with autism.

Elevated unanticipated acoustic startle reactivity in dyslexia.

People with dyslexia, a neurodevelopmental disorder of reading, are highly attuned to the emotional world. Compared with their typically developing peers, children with dyslexia exhibit greater autonomic nervous system reactivity and facial behaviour to emotion- and empathy-inducing film clips. Affective symptoms, such as anxiety, are also more common in children with dyslexia than in those without. Here, we investigated whether the startle response, an automatic reaction that lies at the interface of emotion and reflex, is elevated in dyslexia. We measured facial behaviour, electrodermal reactivity (a sympathetic nervous system measure) and emotional experience in response to a 100 ms, 105 dB unanticipated acoustic startle task in 30 children with dyslexia and 20 comparison children without dyslexia (aged 7-13) who were matched on age, sex and nonverbal reasoning. Our results indicated that the children with dyslexia had greater total facial behaviour and electrodermal reactivity to the acoustic startle task than the children without dyslexia. Across the sample, greater electrodermal reactivity during the startle predicted greater parent-reported anxiety symptoms. These findings contribute to an emerging picture of heightened emotional reactivity in dyslexia and suggest accentuated sympathetic nervous system reactivity may contribute to the elevated anxiety that is often seen in this population.

Autonomic nervous system and endocrine system response to upper or lower cervical spine mobilization in males with persistent post-concussion symptoms: a proof-of-concept trial

ABSTRACT Introduction The peripheral stress response, consisting of the autonomic nervous system (ANS) and hypothalamic pituitary adrenal-axis (HPA-axis), functions to maintain homeostasis in response to stressors. Cervical spine manual therapy has been shown to differentially modulate the stress response in healthy populations. No study has investigated whether cervical spine mobilizations can differentially modulate the stress response in individuals with persistent post-concussion symptoms (PPCS), a population characterized by a dysfunctional stress response. Methods A randomized, controlled, parallel design trial was performed to investigate whether upper or lower cervical spine mobilization can differentially modulate components of the stress response in individuals with PPCS. The outcomes were salivary cortisol (sCOR) concentration (primary) and the HRV metric, rMSSD, measured with a smartphone application (secondary). Nineteen males diagnosed with PPCS, aged 19–35, were included. Participants were randomly assigned into either intervention group, upper (n = 10) or lower (n = 9) cervical spine mobilization. Each outcome was collected at different time points, pre- and post-intervention. Statistical analyses were performed using the Friedman’s Two-Way ANOVA, Mann-Whitney U test, and Wilcoxon Signed Rank Test. Results There was a statistically significant within-group reduction in sCOR concentration 30 minutes following lower cervical spine mobilizations and statistically significant within-group increase in rMSSD 30 minutes following upper cervical spine mobilizations. Conclusion The results of this trial provide preliminary evidence for cervical spine mobilizations to differentially modulate components of the stress response at specific time points. Understanding the mechanisms of the effect of cervical spine mobilizations on the stress response provides a novel rationale for selecting cervical spine mobilizations to rehabilitate individuals with PPCS.

Acute Autonomic Nervous System Response to Direct Sacral Nerve Root Stimulation in Lower Urinary Tract Dysfunction: A New Approach to Understand the Mechanism of Action of Sacral Nerve Modulation.

Our goal was to assess acute autonomic nervous system (ANS) response to direct sacral nerve root (SNR) stimulation in the context of lower urinary tract dysfunction. In this retrospective monocentric study, patients undergoing 2-stage sacral nerve modulation for overactive bladder, nonobstructive urinary retention, or chronic bladder pain syndrome between March 2022 and June 2023 were analyzed. A standardized stimulation protocol was applied during the lead implantation, each of the 4 contact points being sequentially stimulated at the amplitude required to elicit anal motor response. Stimulations were labeled as StimA, StimB, StimC, and StimD, ordered by ascending order of minimum amplitude required for anal motor response. Heart rate variability parameters were collected using PhysioDoloris Monitor, and computed through the time-domain (standard deviation of normal-to-normal intervals [SDNN], root mean square of successive differences), the frequency-domain (low frequency, high frequency) and the graphical (Analgesia Nociception Index [ANI]) methods. Fifty patients were analyzed, including 35 females. Twelve patients had an underlying neurological disease. Efficacy was deemed achieved in 54% of patients. SDNN variability significantly increased during StimA to StimC, while maximum SDNN significantly increased only during StimA. ANI variability significantly increased during all 4 stimulations, while maximum ANI significantly increased only during StimA. Direct stimulation of SNR is responsible for a significant increase in ANS and relative parasympathetic nervous system activity, with a greater effect observed when the stimulation was delivered closer to the SNR. These results shed light on potential mechanisms underlying sacral nerve modulation, particularly regarding the treatment of ANS dysregulation in lower urinary tract dysfunction.

Examining the Influence of Cognitive Load and Environmental Conditions on Autonomic Nervous System Response in Military Aircrew: A Hypoxia-Normoxia Study.

Executing flight operations demand that military personnel continuously perform tasks that utilize low- and high-order cognitive functions. The autonomic nervous system (ANS) is crucial for regulating the supply of oxygen (O2) to the brain, but it is unclear how sustained cognitive loads of different complexities may affect this regulation. Therefore, in the current study, ANS responses to low and high cognitive loads in hypoxic and normoxic conditions were evaluated. The present analysis used data from a previously conducted, two-factor experimental design. Healthy subjects (n = 24) aged 19 to 45 years and located near Fort Novosel, AL, participated in the parent study. Over two, 2-h trials, subjects were exposed to hypoxic (14.0% O2) and normoxic (21.0% O2) air while simultaneously performing one, 15-min and one, 10-min simulation incorporating low- and high-cognitive aviation-related tasks, respectively. The tests were alternated across five, 27-min epochs; however, only epochs 2 through 4 were used in the analyses. Heart rate (HR), HR variability (HRV), and arterial O2 saturation were continuously measured using the Warfighter MonitorTM (Tiger Tech Solutions, Inc., Miami, FL, USA), a previously validated armband device equipped with electrocardiographic and pulse oximetry capabilities. Analysis of variance (ANOVA) regression models were performed to compare ANS responses between the low- and high-cognitive-load assessments under hypoxic and normoxic conditions. Pairwise comparisons corrected for familywise error were performed using Tukey's test within and between high and low cognitive loads under each environmental condition. Across epochs 2 through 4, in both the hypoxic condition and the normoxic condition, the high-cognitive-load assessment (MATB-II) elicited heightened ANS activity, reflected by increased HR (+2.4 ± 6.9 bpm) and decreased HRV (-rMSSD: -0.4 ± 2.7 ms and SDNN: -13.6 ± 14.6 ms). Conversely, low cognitive load (ADVT) induced an improvement in ANS activity, with reduced HR (-2.6 ± 6.3 bpm) and increased HRV (rMSSD: +1.8 ± 6.0 ms and SDNN: vs. +0.7 ± 6.3 ms). Similar observations were found for the normoxic condition, albeit to a lower degree. These within-group ANS responses were significantly different between high and low cognitive loads (HR: +5.0 bpm, 95% CI: 2.1, 7.9, p < 0.0001; rMSSD: -2.2 ms, 95% CI: -4.2, -0.2, p = 0.03; SDNN: -14.3 ms, 95% CI: -18.4, -10.1, p < 0.0001) under the hypoxic condition. For normoxia, significant differences in ANS response were only observed for HR (+4.3 bpm, 95% CI: 1.2, 7.4, p = 0.002). Lastly, only high cognitive loads elicited significant differences between hypoxic and normoxic conditions but just for SDNN (-13.3 ms, 95% CI, -17.5, -8.9, p < 0.0001). Our study observations suggest that compared to low cognitive loads, performing high-cognitive-load tasks significantly alters ANS activity, especially under hypoxic conditions. Accounting for this response is critical, as military personnel during flight operations sustain exposure to high cognitive loads of unpredictable duration and frequency. Additionally, this is likely compounded by the increased ANS activity consequent to pre-flight activities and anticipation of combat-related outcomes.

Seven robust and easy to obtain biomarkers to measure acute stress

With the purpose of identifying a sensitive, robust, and easy-to-measure set of biomarkers to assess stress reactivity, we here study a large set of relatively easy to obtain markers reflecting subjective, autonomic nervous system (ANS), endocrine, and inflammatory responses to acute social stress (n = 101). A subset of the participants was exposed to another social stressor the next day (n = 48) while being measured in the same way. Acute social stress was induced following standardized procedures. The markers investigated were self-reported positive and negative affect, heart rate, electrodermal activity, salivary cortisol, and ten inflammatory markers both in capillary plasma and salivary samples, including IL-22 which has not been studied in response to acute stress in humans before. Robust effects (significant effect in the same direction for both days) were found for self-reported negative affect, heart rate, electrodermal activity, plasma IL-5, plasma IL-22, salivary IL-8 and salivary IL-10. Of these seven markers, the participants’ IL-22 responses on the first day were positively correlated to those on the second day. We found no correlations between salivary and capillary plasma stress responses for any of the ten cytokines and somewhat unexpectedly, cytokine responses in saliva seemed more pronounced and more in line with previous literature than cytokines in capillary plasma. In sum, seven robust and easy to obtain biomarkers to measure acute stress response were identified and should be used in future stress research to detect and examine stress reactivity. This includes IL-22 in plasma as a promising novel marker.

Listening handicap in tinnitus patients with normal extended high frequencies from the perspective of the autonomic nervous system–Effort or fatigue?

ObjectiveIn previous studies, the results regarding the presence of listening effort or fatigue in tinnitus patients were inconsistent. The reason for this inconsistency could be that extended high frequencies, which can cause listening handicap, were not within normal limits. Therefore, this study aimed to evaluate the listening skills in tinnitus patients by matching the normal hearing thresholds at all frequencies, including the extended high frequency. MethodsEighteen chronic tinnitus patients and thirty matched healthy controls having normal pure-tone average with symmetrical hearing thresholds was included. Subjects were evaluated with 0.125–20 kHz pure-tone audiometry, Montreal cognitive assessment test (MoCA), Tinnitus Handicap Inventory (THI), Matrix Test, Pupillometry. ResultsPupil dilatation in the 'coding' phase of the sentence presented in tinnitus patients was less than in the control group (p < 0.05). There was no difference between the groups for Matrix test scores (p > 0.05) Also, there was no statistically significant correlation between THI and Pupillometry components nor between MoCA (p > 0.05). ConclusionEven though tinnitus patients had normal hearing in the range of 0.125–20 kHz, their autonomic nervous system responses during listening differed from healthy subjects. This difference was interpreted for potential listening fatigue in tinnitus patients.

Effect of the early diastolic blood pressure response to the head-up tilt test on the recurrence of benign paroxysmal positional vertigo.

Otolith organ acts complementarily with the autonomic nervous system to maintain blood pressure. However, the effect of blood pressure variability in the autonomic nervous system on otolith organ has not yet been determined. This study aimed to verify the hypothesis that blood pressure variability in the autonomic nervous system affects the recurrence of benign paroxysmal positional vertigo (BPPV), which is the most common disease of the vestibular organs, by using the head-up tilt test (HUTT). This study included 432 patients diagnosed with idiopathic BPPV. The follow-up period for all patients was 12 months. Age, sex, hypertension, diabetes and recurrence were analyzed. The HUTT parameters were divided into a group of patients whose average diastolic blood pressure increased in the upright position compared to supine position during the HUTT (DBP1) and a group of patients whose average diastolic blood pressure decreased in the upright position compared to supine position during the HUTT (DBP2). Model selection, general loglinear analysis, and logit loglinear analysis were performed using a hierarchically progressing loglinear analysis. In summary, the group with increased average diastolic blood pressure (DBP1) showed a higher tendency for BPPV recurrence compared to the group with decreased diastolic blood pressure (DBP2) in the upright position during the HUTT, although the difference was not statistically significant (p = 0.080). However, in males, the DBP1 group demonstrated a significantly higher recurrence rate of BPPV than the DBP2 group during the HUTT (95% CI, -20.021 to -16.200; p < 0.001). It is presumed that poor autonomic nervous system response through vestibulosympathetic reflex maintains elevated diastolic blood pressure in the upright position during the HUTT. This variability is assumed to affect the recurrence of BPPV.

Cortical Sources And Autonomic Nervous System Response Of Listening To North Indian Classical Music

BACKGROUND: Music can affect the human brain and qEEG with its sub-second resolution can be used to study brain activity. The North Indian classical music’s (NICM) effect on brain activity is largely undiscovered. OBJECTIVE: To find out the cortical sources activated along with the autonomic nervous system response while listening to NICM. Methods: 30 Indian subjects (Mean age- 26.1 and (SD) - 1.4 years) were asked to listen to 4 NICM ragas of 5 minutes each with increasing minor note to major note ratio i.e., M1(0), M2(0.16), M3(0.4), M4(1.33).128 channel of EEG signal was recorded which was preprocessed and cortical source localization was done using sLORETA.The autonomic nervous system response while listening to each music excerpt was assessed using Heart Rate Variability parameters by measuring lead II electrocardiography. RESULTS: The cortical sources analysis showed increased activation in cortical regions associated with the extraction of acoustic features of music (superior, middle, and inferior temporal gyruses in addition to fusiform and supramarginal gyrus), emotion generation (precuneus and inferior frontal gyri) and Default Mode Network (posterior cingulate cortex, medial prefrontal cortex, and inferior parietal lobule) while listening to M1. There was a decreased activation in these areas while listening to M2, M3 &amp; M4 (as the minor notes increased).The mean heart rate was significantly higher while listening to M4. There was a reduction in HF while listening to M4 and M3.There was a significant decrease in RMSSD while listening to M4 as compared to the resting state. CONCLUSION: Music can affect brain activity and autonomic function. Music with major notes causes activation of DMN areas causing mind wandering and self-referential mental activity than music with minor notes which decreases DMN activity.In terms of autonomic function increase in minor notes caused decrease in RMSSD and HF signifying an increase in stress and reduced parasympathetic tone. The authors declare no competing interest. The study was approved by the Institutional Review Board (IRB). No Grant was used. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Design of Training Load Monitoring and Adjustment Algorithm for Athletes: Based on Heart Rate Variability and Body Index Data

The training load monitoring and adjustment algorithm for athletes, based on heart rate variability (HRV) and body index data, offers a comprehensive approach to optimizing athletic performance and minimizing the risk of injury. By leveraging HRV data, which reflects the autonomic nervous system's response to training stress, and body index measurements such as body mass index (BMI) or body fat percentage, the algorithm provides insights into athletes' physiological readiness and recovery status. The design of an effective training load monitoring and adjustment algorithm is critical for optimizing athletic performance while minimizing the risk of injury and overtraining. This paper proposes a novel approach that integrates heart rate variability (HRV) and body index data to tailor training programs to individual athlete needs. This paper presents an innovative approach to training load monitoring and adjustment for athletes, utilizing heart rate variability (HRV) and body index data. Through continuous monitoring and analysis of HRV metrics such as RMSSD and LF/HF Ratio, in conjunction with body mass index (BMI) and body fat percentage, personalized load management strategies are developed to optimize athletic performance while mitigating the risk of injury and overtraining. The optimization algorithm outlined in this study allows for real-time adjustments to training loads based on individual physiological responses, ensuring that athletes receive tailored training programs that maximize performance gains and promote long-term health and well-being. By leveraging HRV and body index data, coaches and sports scientists can enhance athletic performance outcomes and support the overall development and longevity of athletes' careers.

Cortical Sources and Autonomic Nervous System Response of Listening to North Indian Classical Music (P11-1.008)

Cortical Sources and Autonomic Nervous System Response of Listening to North Indian Classical Music (P11-1.008)

Comparing multimodal physiological responses to social and physical pain in healthy participants.

Previous physiology-driven pain studies focused on examining the presence or intensity of physical pain. However, people experience various types of pain, including social pain, which induces negative mood; emotional distress; and neural activities associated with physical pain. In particular, comparison of autonomic nervous system (ANS) responses between social and physical pain in healthy adults has not been well demonstrated. We explored the ANS responses induced by two types of pain-social pain, associated with a loss of social ties; and physical pain, caused by a pressure cuff-based on multimodal physiological signals. Seventy-three healthy individuals (46 women; mean age = 20.67 ± 3.27 years) participated. Behavioral responses were assessed to determine their sensitivity to pain stimuli. Electrocardiogram, electrodermal activity, photoplethysmogram, respiration, and finger temperature (FT) were measured, and 12 features were extracted from these signals. Social pain induced increased heart rate (HR) and skin conductance (SC) and decreased blood volume pulse (BVP), pulse transit time (PTT), respiration rate (RR), and FT, suggesting a heterogeneous pattern of sympathetic-parasympathetic coactivation. Moreover, physical pain induced increased heart rate variability (HRV) and SC, decreased BVP and PTT, and resulted in no change in FT, indicating sympathetic-adrenal-medullary activation and peripheral vasoconstriction. These results suggest that changes in HR, HRV indices, RR, and FT can serve as markers for differentiating physiological responses to social and physical pain stimuli.

Heart rate variability: Obtaining the stress score from SDNN values

BACKGROUND: Heart Rate Variability (HRV) is a non-invasive method of assessing the autonomic nervous system response during exercise and fatigue. OBJECTIVE: The aim of the study was to analyze the validity and feasibility of the stress score index (SS) calculated from SDNN values during exercise. METHODS: 18 Men performed 2 running tests: 1) incremental exercise test; 2) 10-minute constant load test. Subjects underwent HRV analysis during the constant load test, before both tests, and afterward in a seated position at 3 intervals (0’–5’, 5’–10’, 10’–15’). The relationship between SDNN and SD2 was analyzed before, during, and after the test. SS was calculated as 1/SD2*1000. The Bland-Altman test analyzed the reliability of ESS. The bias, limits of agreement (LoA), standard deviation of difference, intraclass correlation (ICC), and person coefficient were calculated. RESULTS: The bias was 0.15 ± 2.54 (UperLOA: 2.54; LowerLOA: -2.23). In all conditions, SD2 and SDNN showed a positive linear relationship (r2 = 0.986); SS and ESS were correlated; and SS and ESS described a positive linear relationship (r2 = 0.993). CONCLUSIONS: The SS index calculation from SDNN is a reliable alternative during exercise.

Modification of heart rate variability induced by focal muscle vibration in patients with severe acquired brain injury

ABSTRACT Background/Purpose Heart rate variability (HRV) is a biomarker of autonomic nervous system (ANS) reaction in persons with severe acquired brain injury (sABI) who undergo a rehabilitation treatment, such as focal muscle vibration (FMV). This study aims to evaluate if and how FMV can modulate HRV and to compare potential differences in FMV modulation in HRV between patients with sABI and healthy controls. Methods Ten patients with sABI and seven healthy controls have been recruited. Each individual underwent the same stimulation protocol (four consecutive trains of vibration of 5 minutes each with a 1-minute pause). HRV was analyzed through the ratio of frequency domain heart-rate variability (LF/HF). Results In the control group, after performing FMV, a significant LF/HF difference was observed in the in the second vibration session compared to the POST phase. Patients with SABI treated on the affected side showed a statistically significant LF/HF difference in the PRE compared to the first vibration session. Conclusion These preliminary results suggest that FMV may modify the cardiac ANS activity in patients with sABI.