Autonomic Nervous System Research Articles

The level of partial pressure of carbon dioxide affects organ perfusion in respiratory failure patients undergoing pressure support ventilation with venovenous extracorporeal membrane oxygenation: a prospective study

BackgroundWe evaluated the influence of different partial carbon dioxide pressure (PaCO2) levels on organ perfusion in patients with respiratory failure receiving pressure-support ventilation with veno-venous extracorporeal membrane oxygenation (V-V ECMO).MethodsIn this twelve patients prospective study, ECMO gas-flow was decreased from baseline (PaCO2 < 40 mmHg) until PaCO2 increased by 5–10 mmHg (High-CO2 phase). Resistance indices of gut, spleen, and snuffbox artery, the peripheral perfusion index (PPI), and heart rate variability were measured at baseline and High-CO2 phase.ResultsWhen PaCO2 increased from 36 (36–37) mmHg at baseline to 42 (41–43) mmHg in the High-CO2 phase (p < 0.001), PPI decreased significantly (p = 0.026). The snuffbox artery (p = 0.022), superior mesenteric artery (p = 0.042), and spleen (p = 0.012) resistance indices increased significantly. The root mean square of successive differences (RMSSD) decreased from 19.5(18.1–22.7) to 15.9(14.4–18.6) ms (p = 0.034), and the ratio of low-frequency to high-frequency components(LF/HF) increased from 0.47 ± 0.23 to 0.70 ± 0.38 (p = 0.013).ConclusionsHigh PaCO2 might cause decreased peripheral tissue and visceral organ perfusion through autonomic nervous system in patients with respiratory failure undergoing PSV with V-V ECMO.

Association between change in heart rate over years and life span in the Paris Prospective 1, the Whitehall 1, and Framingham studies.

Heart rate, a measure of the frequency of the cardiac cycle, reflects the health of the cardiovascular system, metabolic rate, and activity of the autonomic nervous system. Whether changes in resting heart rate are related to lifespan has not yet been explored to our best knowledge. In this study, we examined the association between resting heart rate and lifespan using linear regression in the Paris Prospective Study I, the Whitehall I Study, and the Framingham Heart Study. We used Cox proportional hazards regression to relate changes in heart rate over years to mortality risk. We observed a statistically significant association between increases in resting heart rate over a 5-year period and risk of mortality in the Paris Prospective Study I (HR mortality per 10 bpm increase over time: 1.20; 95% CI: 1.13 to 1.27) and over an 8-year period in the Framingham Heart Study (HR: 1.13; 95% CI: 1.07 to 1.19 for men and HR: 1.09; 95% CI: 1.04 to 1.15 for women), after adjusting for classical risk factors and resting heart rate. Our study shows that men and women who increase their resting heart rate over time increase their risk of mortality.

Effects of Local Vasodilators and the Autonomic Nervous System on Microcirculation and Mitochondrial Function in Septic Rats.

Systemic vasodilating agents like nitroglycerin (NG) or iloprost (Ilo) show beneficial effects on intestinal microcirculation during sepsis, which could be attenuated by activation of the sympathetic nervous system or systemic side effects of vasodilating agents. This exploratory study aimed to investigate the effects of topically administered vasodilators and the parasympathetic drug carbachol on colonic microcirculatory oxygenation (µHbO2), blood flow (µFlow) and mitochondrial respiration. A total of 120 male Wistar rats were randomly assigned to twelve groups and underwent either colon ascendens stent peritonitis (CASP) or sham surgery. After 24 h, animals received the following therapeutic regimes: (1) balanced full electrolyte solution, (2) carbachol, (3) NG, (4) Ilo, (5) NG + carbachol, and (6) Ilo + carbachol. Mitochondrial respiration was measured in colon homogenates by respirometry. In sham animals, NG (-13.1%*) and Ilo (-10.5%*) led to a decrease in µHbO2. Additional application of carbachol abolished this effect (NG + carbachol: -4.0%, non-significant; Ilo + carbachol: -1.4%, non-significant). In sepsis, carbachol reduced µHbO2 when applied alone (-10.5%*) or in combination with NG (-17.6%*). Thus, the direction and degree of this effect depend on the initial pathophysiologic condition.

Preterm birth risk stratification through longitudinal heart rate and HRV monitoring in daily life

Preterm birth (PTB) remains a global health concern, impacting neonatal mortality and lifelong health consequences. Traditional methods for estimating PTB rely on electronic health records or biomedical signals, limited to short-term assessments in clinical settings. Recent studies have leveraged wearable technologies for in-home maternal health monitoring, offering continuous assessment of maternal autonomic nervous system (ANS) activity and facilitating the exploration of PTB risk. In this paper, we conduct a longitudinal study to assess the risk of PTB by examining maternal ANS activity through heart rate (HR) and heart rate variability (HRV). To achieve this, we collect long-term raw photoplethysmogram (PPG) signals from 58 pregnant women (including seven preterm cases) from gestational weeks 12–15 to three months post-delivery using smartwatches in daily life settings. We employ a PPG processing pipeline to accurately extract HR and HRV, and an autoencoder machine learning model with SHAP analysis to generate explainable abnormality scores indicative of PTB risk. Our results reveal distinctive patterns in PTB abnormality scores during the second pregnancy trimester, indicating the potential for early PTB risk estimation. Moreover, we find that HR, average of interbeat intervals (AVNN), SD1SD2 ratio, and standard deviation of interbeat intervals (SDNN) emerge as significant PTB indicators.

Orthostatic Vital Signs After Sport-Related Concussion: A Cohort Study

Background: The 6th International Consensus Statement on Concussion in Sport guidelines identified that measuring autonomic nervous system dysfunction using orthostatic vital signs (VSs) is an important part of the clinical evaluation; however, there are limited data on the frequency of autonomic nervous system dysfunction captured via orthostatic VSs after concussion. Purpose: To compare orthostatic changes in heart rate (HR), systolic blood pressure (SBP), and diastolic blood pressure (DBP) between athletes with acute sport-related concussion (SRC) and control athletes. Study Design: Cross-sectional study; Level of evidence, 3. Methods: We compared 133 athletes (mean age, 15.3 years; age range, 8-28 years; 45.9% female) with acute SRC (<30 days after injury) with 100 control athletes (mean age, 15.7 years; age range, 10-28 years; 54.0% female). Given the broad age range eligible for study inclusion, participants were subdivided into child (younger than 13 years of age), adolescent (13-17 years of age), and adult (18 years of age and older) age groups for subanalyses. Participants completed a single standard orthostatic VS evaluation including HR, SBP, and DBP in the supine position then immediately and 2 minutes after standing. Linear regression was used to compare delayed supine-to-standing changes in HR, SBP, and DBP as a continuous variable (ΔHR, ΔSPB, and ΔDBP) between groups, and logistic regression was used to compare patients with positive orthostatic VS changes (sustained HR increase ≥30 beats per minute [bpm], SBP decrease ≥20 mm Hg, and DBP ≥10 mm Hg at 2 minutes) between groups, accounting for age and sex. Results: Between-group differences were present for delayed ΔHR (18.4 ± 12.7 bpm in patients with SRC vs 13.2 ± 11.0 bpm in controls; P = .002) and ΔSPB (–3.1 ± 6.6 bpm in patients with SRC vs –0.4 ± 6.5 bpm in controls; P = .001), with positive orthostatic HR changes present more frequently in patients with SRC (18% vs 7%; odds ratio, 2.79; P = .027). In the SRC group, a weak inverse relationship was present between age and ΔHR (r = –0.171; P = .049), with positive orthostatic HR findings occurring primarily in the child and adolescent SRC subgroups. Conclusion: Patients with acute SRC had greater orthostatic VS changes compared with controls, the most prominent being sustained HR elevations. Clinical evaluation of autonomic change after SRC via standard orthostatic VS assessment may be a helpful clinical biomarker in the assessment of SRC, especially in children and adolescents.

Machine Learning and Wearable Technology: Monitoring Changes in Biomedical Signal Patterns during Pre-Migraine Nights.

Migraine is one of the most common neurological disorders, characterized by moderate-to-severe headache episodes. Autonomic nervous system (ANS) alterations can occur at phases of migraine attack. This study investigates patterns of ANS changes during the pre-ictal night of migraine, utilizing wearable biosensor technology in ten individuals. Various physiological, activity-based, and signal processing metrics were examined to train predictive models and understand the relationship between specific features and migraine occurrences. Data were filtered based on specified criteria for nocturnal sleep, and analysis frames ranging from 5 to 120 min were used to improve the diversity of the training sample and investigate the impact of analysis frame duration on feature significance and migraine prediction. Several models, including XGBoost (Extreme Gradient Boosting), HistGradientBoosting (Histogram-Based Gradient Boosting), Random Forest, SVM, and KNN, were trained on unbalanced data and using cost-sensitive learning with a 5:1 ratio. To evaluate the changes in features during pre-migraine nights and nights before migraine-free days, an analysis of variance (ANOVA) was performed. The results showed that the features of electrodermal activity, skin temperature, and accelerometer exhibited the highest F-statistic values and the most significant p-values in the 5 and 10 min frames, which makes them particularly useful for the early detection of migraines. The generalized prediction model using XGBoost and a 5 min analysis frame achieved 0.806 for accuracy, 0.638 for precision, 0.595 for recall, and 0.607 for F1-score. Despite identifying distinguishing features between pre-migraine and migraine-free nights, the performance of the current model suggests the need for further improvements for clinical application.

Lost at sea: Impact of an ocean survival experience on psychological, physiological and cognitive abilities (RAD'LÔ)

Survival in an extreme environment places high physiological and cognitive demands on the individual. These environments are characterized by specific stimuli, including unusual sensory stimulation and uncertainty, which induce intense stress. Thus, the aims of this study are: i) to evaluate the impact of a five-day survival at sea simulation on human adaptive capacities, based on the assessment of psychological, cognitive, physiological, and sensorial measures; and ii) to assess recovery. Twenty-one healthy participants were enrolled in a 5-day simulation onboard a lifeboat or an inflatable raft. Psychological, physiological, sensory, and cognitive measurements were recorded before leaving (baseline), at the end of the experiment (post) and during the week that followed (recovery). Our results are unequivocal. The harshness of the environment affected the majority of the organism's responses. On the cognitive level, performance significantly deteriorated. On the psychological level, there was low mood, a decrease in subjective exteroceptive acuity and sleep disorders, increased energy, and less perceived stress. On the physiological level, a decline was recorded with respect to autonomous nervous system measurements. On the sensory level, we observed a state of hypervigilance and hypersensitivity to stimuli from the external environment. Proprioception was deeply impacted. Moreover, at recovery, many individuals did not fully recover or deteriorated further, especially regarding sleep, interoceptive abilities and sensory distortion. It appears that participants entered a state of psychological hibernation, associated with increased physical and cognitive load, and sensory hypervigilance. These results raise the question of the risks that may be incurred during future long-term space missions, as astronauts will have to maintain their cognitive performance at a high level to be able to respond to environmental demands and remain alive. It is essential to continue to explore countermeasures that will support adaptation in future spacecraft crew.

Heart brain axis in health and disease: role of innate and adaptive immunity.

The importance of the brain-heart interaction has been increasingly recognized as a critical physiological axis that is altered in disease. In this review, we explore the intricate relationship between the central nervous system and cardiovascular health, focusing particularly on immunological mechanisms that influence the course of both neurological and cardiovascular diseases. While previous studies have established a key role of the autonomic nervous system in linking brain and the heart, more recent studies have expanded our understanding of the multifaceted inter-organ interactions. As such, circulating mediators include immune cells of the adaptive and innate immune system and their secreted immunogenic factors have come into the focus as mediators along this bidirectional communication. Hence, in this review we briefly discuss the contribution of the autonomic nervous system and then focus on innate and adaptive immune mechanisms along the heart-to-brain and brain-to-heart axes, illustrating how cardiovascular diseases affect cognitive functions and how brain pathologies lead to cardiac complications.

Effect of bedroom environment on sleep and physiological parameters for individuals with good sleep quality: A pilot study

Bedroom conditions affect sleep, overall health, and well-being. Field studies reporting measurements of bedroom environment and sleep parameters are almost lacking in the scientific community since the majority of research has been conducted in laboratories. To fill this knowledge gap, we have investigated the associations among bedroom environmental factors (temperature, humidity, CO2, pressure), measured sleep and physiological parameters (heart rate, heart rate variability, and breathing rate) in participants with good sleep quality. Six subjects were enrolled in the study, possessing a minimum of two years of experience in using the wrist actigraph chosen for the experimentation, and exhibiting good sleep quality. The air quality measurements were conducted using the air quality monitor, whereas advanced actigraphs were employed for the assessment of various sleep stage durations. The statistical analysis, carried out applying Linear Mixed Models, revealed that an increase of 100 ppm of CO2 concentration levels is associated with an approximate 0.29 % decline in sleep quality whereas, concerning the effect of the relative humidity, we observed a 0.1 % reduction in sleep quality associated with a 1 % rise in RH. On the other hand, a 1 °C rise in air temperature is associated with an approximate 0.16 % reduction in sleep efficiency, and, at a CO2 concentration of about 900 ppm, the autonomic nervous system (ANS) indicator remains positive for temperature values < 20 °C. These results contribute to mounting evidence underscoring the crucial role of the bedroom atmosphere in facilitating high-quality sleep.

A Spaced Repetition Approach to Presenting Autonomic Nervous System Pharmacology Curricula in Medical Education

A Spaced Repetition Approach to Presenting Autonomic Nervous System Pharmacology Curricula in Medical Education

Monitoring the heart rate variability of servicewomen of the Armed Forces of Ukraine during the legal regime of martial law

The article features the results of the analysis of heart rate variability of 30 female military personnel (n=30). The purpose of this study was to assess the state of regulatory mechanisms of the autonomic nervous system. The analysis of heart rate variability indicators reflects the general level of autonomic regulation, which is important for assessing the physical and psychological state of military personnel. The RRNN parameter had a median of 814.5 ms, which corresponds to the norm for healthy individuals and indicates a normal level of cardiac activity of females being under the research. The SDNN indicator, which characterizes the total effect of autonomic regulation of blood circulation, was 37.4 ms on the median, which also corresponds to the norm and indicates an adequate level of adaptation capabilities of the body. However, RMSSD was at the median below normal, indicating reduced recovery and high levels of stress among female military personnel. pNN50, which reflects the proportion of consecutive RR intervals differing by more than 50 ms, was also below normal, further confirming reduced parasympathetic activity. The LF index was 301.0 ms² on the median of female military personnel, which is at the lower limit of the norm. The result we obtained may indicate a reduced sympathetic influence or a general depletion of adaptation reserves. The VLF indicator, which characterizes neurohumoral regulation, was also below the norm, which indicates a possible depletion of the body's adaptive reserves. Such studies make it possible to detect signs of fatigue or insufficient recovery in time and take the necessary measures to optimize the training process and the performance of official duties. Our research confirms that heart rate variability is an important indicator of the body's adaptive capabilities, especially in the conditions of martial law, where stress and physical exertion are constant factors of influence.

Analysis of perioperative autonomic nervous system activity to visualize stress in pediatric patients undergoing alveolar bone graft surgery.

Perioperative stress in pediatric patients is often difficult to assess via interviews; thus, an objective measure to assess perioperative stress is needed. To visualize perioperative stress, we observed autonomic nervous system (ANS) activity, circulatory dynamics, and psychological status in pediatric patients undergoing alveolar bone grafting under general anesthesia. This prospective observational study included 40 patients aged 8-12 years who were scheduled for alveolar bone grafting in our hospital. ANS activity was analyzed using heart rate variability the day before surgery, during general anesthesia, 2h postoperatively, 24h postoperatively, and the day before discharge. ANS assessment included LF/HF (sympathetic nervous system activity) and HF (parasympathetic nervous system activity). Additionally, heart rate (HR), systolic blood pressure (SBP), face scale (FS) score were recorded. Data from 31 patients, excluding dropouts, were analyzed. The ratio of change to the preoperative value was compared. After surgery, the LF/HF, HR, SBP, and FS score significantly increased (P < 0.01) and HF significantly decreased (2h postoperatively: P < 0.05, 24h postoperatively, before discharge: P < 0.01). SBP recovered to preoperative values 24h postoperatively, and HR and FS scores recovered to preoperative values before discharge. However, even before discharge, LF/HF remained significantly higher than preoperative values, and HF remained significantly lower than preoperative values (P < 0.01). Conclusion We observed perioperative stress from multiple perspectives. Circulatory dynamics and psychological status recovered by the day before discharge; however, ANS activity did not. Therefore, evaluating ANS activity may be useful in visualizing potential perioperative stress in pediatric patients.

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.

Effect of a Group-Based Personal Assistive RObot (PARO) Robot Intervention on Cognitive Function, Autonomic Nervous System Function, and Mental Well-being in Older Adults with Mild Dementia: A Randomized Controlled Trial

ObjectivesPersonal Assistive RObot (PARO) interventions have been used to treat agitation and mood symptoms of dementia effectively. However, the effects of a PARO intervention on physiological and cognitive function are unclear. To examine the effects of a group-based PARO intervention for older adults with mild dementia. DesignUsing a group-based PARO intervention randomized controlled trial with 2-arm parallel groups. Setting and ParticipantsOlder adults with mild dementia aged 65 years or older from 4 dementia day care centers were recruited. MethodsPhysiological parameters were assessed using the finger tapping test (FTT) and heart rate variability (HRV). The Mini-Mental State Examination (MMSE), Geriatric Depression Scale–Short Form (GDS-SF), University of California Los Angeles loneliness scale–version 3 (UCLA-3), and Warwick-Edinburgh Mental Well-being Scale (WEMWBS) were assessed before the intervention, end of the intervention, and 1-month after the intervention. ResultsUsing a repeated-measures generalized linear model, significant time × group interactions were found in the MMSE [F(2, 115) = 19.54, P < .001], FTT [F(2, 115) = 4.87, P = .01], HRV high-frequency [F(2, 115) = 3.57, P = .03], and high-frequency/low-frequency ratio [F(2, 115) = 0.96, P = .01], UCLA-3 [F(2, 115) = 54.7, P < .001], GDS-SF [F(2, 115) = 3.36, P = .04], and WEMWBS [F(2, 115) = 5.93, P < .001]. Furthermore, psychological parameters improved significantly and continuously even 1 month after the PARO intervention was finished. Physiological parameters significantly improved at week 6, but the effects had diminished by week 10. Conclusions and ImplicationsA PARO intervention may effectively improve the physiological and psychological responses of people with mild dementia.

Assessing the Role of the Autonomic Nervous System as a Driver of Sleep Quality in Patients With Multiple Sclerosis: Observation Study

Background Low sleep quality is a common symptom of multiple sclerosis (MS) and substantially decreases patients’ quality of life. The autonomic nervous system (ANS) is crucial to healthy sleep, and the transition from wake to sleep produces the largest shift in autonomic activity we experience every day. For patients with MS, the ANS is often impaired. The relationship between the ANS and perceived sleep quality in patients with MS remains elusive. Objective In this study, we aim to quantify the impact of the ANS and MS on perceived sleep quality. Methods We monitored 77 participants over 2 weeks using an arm-worn wearable sensor and a custom smartphone app. Besides recording daily perceived sleep quality, we continuously recorded participants’ heart rate (HR) and HR variability on a per-second basis, as well as stress, activity, and the weather (20,700 hours of sensor data). Results During sleep, we found that reduced HR variability and increased motion led to lower perceived sleep quality in patients with MS (n=53) as well as the age- and gender-matched control group (n=24). An activated stress response (high sympathetic activity and low parasympathetic activity) while asleep resulted in lower perceived sleep quality. For patients with MS, an activated stress response while asleep reduced perceived sleep quality more heavily than in the control group. Similarly, the effect of increased stress levels throughout the day is particularly severe for patients with MS. For patients with MS, we found that stress correlated negatively with minimal observed HR while asleep and might even affect their daily routine. We found that patients with MS with more severe impairments generally recorded lower perceived sleep quality than patients with MS with less severe disease progression. Conclusions For patients with MS, stress throughout the day and an activated stress response while asleep play a crucial role in determining sleep quality, whereas this is less important for healthy individuals. Besides ensuring an adequate sleep duration, patients with MS might thus work to reduce stressors, which seem to have a particularly negative effect on sleep quality. Generally, however, sleep quality decreases with MS disease progression.

Intracerebroventricular insulin injection acutely normalizes the augmented exercise pressor reflex in male rats with type 2 diabetes mellitus.

The exercise pressor reflex (EPR) is exaggerated in type 2 diabetes mellitus (T2DM), but the underlying central nervous system aberrations have not been fully delineated. Stimulation of muscle afferents within working skeletal muscle activates the EPR, by sending information to neurons in the brainstem, where it is integrated and results in reflexively increased mean arterial pressure (MAP) and sympathetic nerve activity. Brain insulin is known to regulate neural activity within the brainstem. We hypothesize that brain insulin injection in T2DM rats attenuates the augmented EPR, and that T2DM is associated with decreased brain insulin. Using male Sprague-Dawley rats, T2DM and control rats were generated via an induction protocol with two low doses of streptozotocin (35 and 25mg/kg, i.p.) in combination with a 14-23-week high-fat diet or saline injections and a low-fat diet, respectively. After decerebration, MAP and renal sympathetic nerve activity (RSNA) were evaluated during EPR stimulation, evoked by electrically induced muscle contraction via ventral root stimulation, before and after (1 and 2h post) intracerebroventricular (i.c.v.) insulin microinjections (500mU, 50nl). i.c.v. insulin decreased peak MAP (ΔMAP Pre (36±14mmHg) vs. 1h (21±14mmHg) vs. 2h (11±6mmHg), P<0.05) and RSNA (ΔRSNA Pre (107.5±40%), vs. 1h (75.4±46%) vs. 2h (51±35%), P<0.05) responses in T2DM, but not controls. In T2DM rats, cerebrospinal fluid insulin was decreased (0.41±0.19 vs. 0.11±0.05ng/ml, control (n=14) vs. T2DM (n=4), P<0.01). The results demonstrated that insulin injections into the brain normalized the augmented EPR in brain hypoinsulinaemic T2DM rats, indicating that the EPR can be regulated by brain insulin. KEY POINTS: The reflexive increase in blood pressure and sympathetic nerve activity mediated by the autonomic nervous system during muscle contractions is also known as the exercise pressor reflex. The exercise pressor reflex is dangerously augmented in type 2 diabetes, in both rats and humans. In type 2 diabetic rats both cerebrospinal fluid insulin and phosphoinositide 3-kinase signalling within cardiovascular brainstem neurons decrease in parallel. Brain insulin injections decrease the magnitude of the reflexive pressor and sympathetic responses to hindlimb muscle contraction in type 2 diabetic rats. Partial correction of low insulin within the central nervous system in type 2 diabetes may treat aberrant exercise pressor reflex function.

The Effects of Prolonged Indoor Inhalation of Nature-Derived Odors on Menopausal Women.

This study aimed to investigate the effects of prolonged inhalation of nature-derived odors indoors on humans. Twenty-six women participated in this study. Heart rate variability, heart rate, blood pressure, pulse rate, estradiol, testosterone, and cortisol were used as indicators of autonomic nervous system and endocrine system activities. Profile of mood state, state-trait anxiety inventory, menopause rating scale and general sleep disturbance scale were used as psychological indicators. The order was as follows: After the participants relaxed in a chair for 5 min, their heart rate variability and heart rate were measured for 3 min with their eyes closed. Subsequently, blood pressure and pulse rate were measured, salivary samples were collected for estradiol, testosterone, and cortisol analyses, and a subjective assessment was conducted. The participants received a diffuser containing fir essential oil and were instructed on its usage and precautions. Subsequently, they returned home and inhaled the fir oil for a week. After 7 days, participants revisited the laboratory for posttest measurements, conducted at the same time as the pretest. Prolonged inhalation of the fir essential oil resulted in increased estradiol concentration, decreased systolic and diastolic blood pressure, relief of menopausal symptoms, reduced anxiety levels, improved sleep quality and mood states. Prolonged inhalation of the fir essential oil induced physiological and psychological relaxation on menopausal women.

Navigating Complexity in Postural Orthostatic Tachycardia Syndrome.

Postural Orthostatic Tachycardia Syndrome (POTS) affects up to 1% of the US population, predominantly women, and is characterized by a complex, elusive etiology and heterogeneous phenotypes. This review delves into the intricate physiology and etiology of POTS, decoding the roles of the sinoatrial node, the autonomic nervous system, fluid dynamics, and the interplay between the immune and endocrine systems. It further examines key contributing factors such as dysautonomia, thoracic hypovolemia, autonomic neuropathies, sympathetic denervation, autoimmune responses, and associations with conditions such as small-fiber neuropathy and mast cell activation syndrome. Given the numerous mysteries surrounding POTS, we also cautiously bring attention to sinoatrial node and myocardial function, particularly in how the heart responds to stress despite exhibiting a normal cardiac phenotype at rest. The potential of genomic research in elucidating the underlying mechanisms of POTS is emphasized, suggesting this as a valuable approach that is likely to improve our understanding of the genetic underpinnings of POTS. The review introduces a tentative classification system for the etiological factors in POTS, which seeks to capture the condition's diverse aspects by categorizing various etiological factors and acknowledging co-occurring conditions. This classification, while aiming to enhance understanding and optimize treatment targets, is presented as a preliminary model needing further study and refinement. This review underscores the ongoing need for research to unravel the complexities of POTS and to develop targeted therapies that can improve patient outcomes.

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.

Trajectory of Infant Problematic Feeding Symptoms: Study Protocol.

Infants with developmental risk factors are more likely to have feeding problems and develop chronic feeding disorders. Early detection and understanding of the progression of problematic feeding and its relationship with a child's biological functioning and the family feeding environment will enhance effective symptom management and development of interventions to prevent pediatric feeding disorders. The New Through Two (NewThru2) feeding study protocol is described. Study aims are to (a) characterize symptoms of problematic feeding and trajectories of symptoms from pre-discharge from neonatal intensive care through age 24 months; (b) determine the relationship of child biological function at discharge with symptom characteristics and trajectories; (c) describe the child's feeding environment and its relationship to symptoms from discharge through 24 months; and (d) determine the relationship between problematic feeding symptoms and growth and developmental outcomes. NewThru2 is a prospective, longitudinal, mixed method study following over 200 infants who received care in a neonatal intensive care unit and were identified as at risk for compromised development. The study follows enrolled infants through 24 months of age. Symptoms of problematic feeding are measured pre-discharge by clinical observation and medical record review and post-discharge by parent report. Biological function is measured by medical history and cardiorespiratory and autonomic nervous system function during feeding prior to discharge. Child feeding environment is measured by strategies parents use to manage feeding, the effect of feeding on the parent and family, and the use of feeding services. A subset of parents is interviewed to achieve a contextual understanding of the family feeding environment. Child outcome measures include parent-reported feeding skills and clinician-reported growth and neurodevelopment. The results of this study will improve understanding of pediatric feeding disorders during a time of development sensitive to adequate nutrition and with infants at risk for developmental delays or impairments.