Autonomic Nervous System Responses Research Articles

Reactivity of the autonomic nervous system in children of younger school age with mental retardation

Introduction. The functioning of the autonomic nervous system (ANS) to some extent affects various aspects of human health and general well-being. One of the main ANS functions is to ensure adaptation to the factors of the external and internal environment, carried out by the coordinated activity of the sympathetic and parasympathetic links. Determining the predominant type of ANS reactivity according to the characteristics of the heart rhythm makes it possible to predict the adaptive capabilities of the child’s body in the learning process in a personalized way. 
 The aim of the study was to study the trend in heart rate variability in children with special health conditions associated with disorders of the intellectual development, which characterizes the implementation of mechanisms for adapting the body to the conditions of schooling.
 Materials and methods. We examined one hundred sixty eight 7–11 years children of primary school age, including 54 children with special health abilities (SHA) (F70, F71), and 114 mentally healthy children. The study of heart rate variability was carried out using the hardware-software complex “ORTO Valeo”. There was analyzed TP, HF, LF, VLF, LF / HF; RMSSD, SDNN, Mo, AMo, ΔX, IN, AMo / Mo, Amo / ΔX; type of vegetative regulation.
 Results. In SHA children of primary school age, the LF, VLF, LF / HF indices are increased and HF is decreased relative to the control group, which indicates the predominance of the sympathetic link of the autonomic nervous system over the parasympathetic. When analyzing the spectral components in SHA children of primary school age, VLF (40.6%) and low HF (19.6%) dominate. According to the types of autonomic regulation in SHA children, the following ratio was found 50: 4: 33: 13, the central type of cardiac regulation dominates (type I).
 Limitations. The limitation of the study is due to the specifics of the individuals in the observation group – children of primary school age (7–11 years) with special health opportunities associated with mental retardation.
 Conclusion. SHA children of primary school age have high activity of sympathetic modulation, reduced resistance to stress, high tension of adaptive responses with the dominance of the central type of regulation of the cardiac activity. The revealed imbalance of the parameters of autonomic regulation in SHA children without corrective measures (including correction of physical status, psychoemotional and educational loads) threatens the development of a breakdown of adaptive responses to the effects of various internal and external factors, contributing to asthenization of regulatory systems.

The role of youths' cardiac autonomic balance and parental responses to youth emotion in vulnerability to borderline personality disorder development.

Developmental models of borderline personality disorder (BPD) emphasize the effects of youths' biological vulnerabilities and their experiences of parental responses to emotion, as well as the interaction between these two elements. The current study evaluated the independent and interactive effects of two indices of autonomic nervous system response and parental responses to youth negative emotions on severity and exacerbation of youths' BPD features during the transition to adolescence. The sample consisted of 162 psychiatric youth (10-14 years; 47.2% female) and their parents. At baseline, youth and their parents completed a lab-based conflict discussion during which parasympathetic and sympathetic nervous system response were measured and indices of sympathetic-parasympathetic balance and coactivation/coinhibition were calculated. Youth also reported on supportive and non-supportive parental responses. At baseline and after 9 months, youth self-reported on their BPD features. Results demonstrated that shifting toward sympathetic dominance independently predicted exacerbation of BPD across 9 months. Additionally, fewer experiences of supportive parental responses and more non-supportive parental responses were associated with greater severity of BPD features in youth. This study highlights the role of autonomic response to parent-child conflict as well as the significance of parental responses to youth emotion for the development of BPD during this developmental window.

The mirror viewing experience of women undergoing a mastectomy: An integrative review

To appraise the current literature on the mirror viewing experience of women undergoing a mastectomy. Whittemore and Knafl's approach to integrative reviews, Braun and Clarke's thematic analysis, and PRISMA guidelines were utilized for this review. A systematic search of primary peer-reviewed articles from April 2012 to 2022 was conducted using PubMed, CINAHL, Academic Search Complete and Google Scholar databases. Eighteen studies met the inclusion criteria (15 qualitative and 3 quantitative) and were appraised using the Johns Hopkins evidence-based practice appraisal instrument. Five themes describing the mirror viewing experience were revealed: Mirror viewing motives, mirror viewing preparedness, mirror viewing experience, mirror comfort/avoidance and women's mirror viewing recommendations. The review findings were found to align with Freysteinson's Neurocognitive Mirror Viewing Model highlighting the occurrence of short-term memory disruptions and an autonomic nervous system response that can lead women to experience a flight/fright or faint response, mirror trauma and mirror avoidance when looking at themselves in the mirror after a mastectomy. Women reported feeling unprepared to look at themselves in the mirror, with some experiencing shock and emotional distress, which led to mirror avoidance behaviours as a way to cope with their new body image. Nursing interventions aimed at improving women's mirror viewing experiences may help mitigate this autonomic nervous system response and minimize mirror trauma and mirror avoidance. Preparing women to view themselves in the mirror for the first time may help reduce psychological distress and body image disturbances in women undergoing a mastectomy. This integrative review did not involve patient or public contributions. The authors reviewed currently published peer-reviewed literature in writing this manuscript.

Electrodermal and postural responses in dizzy adults: Diagnostic indicators of vestibular migraine.

No reliable biometric measurement of vestibular involvement with migraine is currently available. Measures of autonomic nervous system and postural responses could serve as quantifiable indicators of vestibular involvement with migraine. A convenience sample of 22 young healthy adults (34±9 years old) and 23 young adults (34±8 years old) diagnosed with vestibular migraine (VM) participated. A rod and frame test and clinical outcome measures of dizziness and mobility were administered. Participants stood on foam while viewing two dynamic virtual environments. Trunk acceleration in three planes and electrodermal activity (EDA) were assessed with wearable sensors. Linear mixed models were used to examine magnitude and smoothness of trunk acceleration and tonic and phasic EDA. A Welch's t-test and associations between measures were assessed with a Pearson Correlation Coefficient. Effect sizes of group mean differences were calculated using Cohen's d. Visual dependence was present in 83% of the VM population. Individuals with VM exhibited lower baseline EDA (t(4.17) = -7.2, p = 0.001) and greater normalized trunk accelerations in the vertical (t(42.5) = 2.861, p = 0.006) and medial (t(46.6) = 2.65, p = 0.01) planes than healthy participants. Tonic EDA activity increased significantly across the period of the trial (F (1,417) = 23.31, p = 0.001) in the VM group. Significant associations appeared between vertical trunk acceleration and EDA, Dizziness Handicap Inventory, and Activities of Balance Confidence tools. Higher tonic EDA activity in healthy adults results in more accurate postural reactions. Results support the supposition that EDA activity and postural acceleration are significantly different between VM and healthy individuals when accommodating for postural instability and visual-vestibular conflict.

Shorter respiratory event duration is related to prevalence of type 2 diabetes.

Obstructive sleep apnea (OSA) is a heterogeneous sleep disorder often comorbid with metabolic diseases, and type 2 diabetes (T2DM) is one of them. Although apnea hypopnea index (AHI) is currently the diagnostic criteria for OSA severity, a controversial relationship between AHI and T2DM has been found. On the other hand, the duration of apnea-hypopnea events has been shown to be a useful metric for predicting mortality. This study aimed to test whether average respiratory event duration was associated with prevalence of T2DM. Patients referred to the sleep clinic were recruited in the study. Baseline clinical characteristics and polysomnography parameters including average respiratory event duration were collected. The association of average respiratory event duration with the prevalence of T2DM was evaluated by univariate and multivariate logistic regression analyses. A total of 260 participants were enrolled, and 92 (35.4%) had T2DM. Univariate analysis revealed that age, body mass index (BMI), total sleep time, sleep efficiency, history of hypertension, and shorter average respiratory event duration were associated with T2DM. In multivariate analysis, only age and BMI remained significant. While average respiratory event duration was insignificant in multivariate analysis, subtype event analysis showed that shorter average apnea duration was both significant in univariate (OR, 0.95; 95% CI, 0.92-0.98) and multivariate analyses (OR, 0.95; 95% CI, 0.91-0.99). Neither average hypopnea duration nor AHI was associated with T2DM. Significant association (OR, 1.19; 95% CI, 1.12-1.25) was observed between shorter average apnea duration and lower respiratory arousal threshold after multivariate adjustment. However, causal mediation analysis revealed no mediating effect of arousal threshold on average apnea duration and T2DM. The average apnea duration may be a useful metric in the diagnosis of OSA comorbidity. Shorter average apnea duration indicating poor sleep quality and augmented autonomic nervous system responses might be the potential pathological mechanisms leading to T2DM.

How Much Stress Does a Surgeon Endure? The Effects of the Robotic Approach on the Autonomic Nervous System of a Surgeon in the Modern Era of Thoracic Surgery

(1) Objective: the purpose of this study was to evaluate and quantify the stress to which a surgeon is subjected during his/her surgical activity; we compared the individual clinical and psychological responses to stress of two surgeons during their surgical activities via robotic and open approaches. (2) Materials and methods: This was a prospective observational study in which we progressively collected data concerning the surgical performances of two different thoracic surgeons (October 2021-June 2022). We evaluated 20 lung resections performed via robot-assisted surgery and 20 lung resections performed via an open approach by each surgeon; in particular, we evaluated a panel of pre-, peri-, and postoperative data concerning the interventions, the patients, and other outcomes concerning the autonomic nervous system (ANS) and psychological responses to stress of the surgeons during their surgical activities. (3) Results: When analyzing data concerning the ANS activity of two surgeons, during robotic activity we found lower maximum, minimum, and mean heart rates; lower mean respiratory frequencies; lower body temperatures; and lower mean desaturations compared to the open approach activity for both surgeons. The psychological monitoring showed that the open approach created more physical fatigue and frustration but higher levels of satisfaction and performance evaluation. The robot-assisted surgeries showed higher levels of anxiety. (4) Conclusions: for different reasons, the robotic approach stimulated the ANS to a lesser degree, causing less stress for surgeons and ensuring greater comfort.

Autonomic nervous system reactivity to emotion and childhood trajectories of relational and physical aggression.

This study investigated the role of autonomic nervous system (ANS) coordination in response to emotion in girls' and boys' development of relational (e.g., ignoring, excluding) and physical (e.g., hitting, kicking) aggression. Caregivers reported on children's relational and physical aggression at ages 6, 7, 8, and 10 years (N = 232, 50.4% girls, 46.6% Latinx). Sympathetic nervous system (assessed via pre-ejection period) and parasympathetic nervous system (assessed via respiratory sinus arrhythmia) reactivity were measured in response to video clips depicting fear, happiness, and sadness at age 7. Growth curve models indicated that ANS reactivity to sadness, but not to fear or happiness, was related to trajectories of relational aggression. In contrast, ANS reactivity to all three emotions was associated with trajectories of physical aggression. Effects differed across genders, indicating that distinct patterns of ANS reactivity to emotion may be involved in girls' and boys' development of aggression. Overall, these findings contribute to a growing literature documenting the role of ANS reactivity to emotion in aggressive behavior. Moreover, this study considers ANS reactivity to specific emotions, as related to both relational and physical aggression, and as differentially expressed among girls versus boys.

Mild daily stress, in interaction with NR3C1 DNA methylation levels, is linked to alterations in the HPA axis and ANS response to acute stress in early adolescents

BackgroundDaily Hassles (DH) or daily stress - is a mild type of stressor with unique contributions to psychological distress. Yet, most prior studies that investigate the effects of stressful life experiences focus on childhood trauma or on early life stress and little is known about the effects of DH on epigenetic changes in stress system related genes and on the physiological response to social stressors. MethodsIn the present study, conducted among 101 early adolescents (mean age = 11.61; SD = 0.64), we investigated whether Autonomic Nervous System (ANS) (namely heart rate and heart rate variability) and Hypothalamic-Pituitary-Adrenal (HPA) axis functioning (measured as cortisol stress reactivity and recovery) are associated with DNA methylation (DNAm) in the glucocorticoid receptor gene (NR3C1), the level of DH and their interaction. To assess the stress system functioning the TSST protocol was used. ResultsOur findings show that higher NR3C1 DNAm in interaction with higher levels of daily hassles, is associated with blunted HPA axis reactivity to psychosocial stress. In addition, higher levels of DH are associated with extended HPA axis stress recovery. In addition, participants with higher NR3C1 DNAm had lower ANS adaptability to stress, specifically lower parasympathetic withdrawal; for heart rate variability this effect was strongest for participants with higher level of DH. ConclusionsThe observation that interaction effects between NR3C1 DNAm levels and daily stress on the functioning of the stress-systems, are already detectable in young adolescents, highlights the importance of early interventions, not only in the case of trauma, but also daily stress. This might help to prevent stress-induced mental and physical disorders later in life.

Psychological skills training impacts autonomic nervous system responses to stress during sport-specific imagery: An exploratory study in junior elite shooters.

This study investigated the effects of psychological skills training (PST) in shooters psychophysiologically using heart rate variability (HRV) in addition to psychological questionnaires and participant interviews. Five junior pistol shooters participated in an 8-week PST program consisting of a group session per week followed by individual counseling. Before and after PST, we collected electrocardiography data during rest, mental imagery of sport-related crisis situations, and successful performance, to analyze differences in HRV indices. Participants also responded to the Psychological Skills Inventory for Archery and Shooting (PSIAS), Intrinsic Motivation Inventory (IMI), Sports Anxiety Scale (SAS), and Trait Sport Confidence Inventory (TSCI). Results showed that the perceived competence (pre: 2.52 ± 0.95, post: 3.36 ± 0.73, p = 0.049) and trait sport confidence (pre: 4.94 ± 1.17, post: 6.60 ± 0.65, p = 0.049) significantly improved after PST. The analysis of HRV indicated that the ratio of low-frequency power to high-frequency power (LF/HF ratio) decreased significantly during imagery of crisis (pre: 3.4 ± 2.3, post: 1.014 ± 0.71, p = 0.038) and success (pre: 1.933 ± 0.917, post: 0.988 ± 0.572, p = 0.046), reflecting a strengthened autonomic nervous system's responsiveness to stress. Our findings illustrate that PST can help athletes better cope with psychologically disturbed situations during competition, by providing psychophysiological evidence through HRV changes.

Beneficial Performance Effects of Training Load Intensification Can Be Abolished by Functional Overreaching: Lessons From a Water Polo Study in Female Athletes.

Brisola, GMP, Dutra, YM, Murias, JM, and Zagatto, AM. Beneficial performance effects of training load intensification can be abolished by functional overreaching: Lessons from a water polo study in female athletes. J Strength Cond Res 37(6): e391-e402, 2023-The purpose of this study was to compare the outcomes from 2 weeks of training load intensification strategy in female water polo players diagnosed with functional overreaching (F-OR) with no F-OR players (acute fatigue) on the performance outcomes and hormonal, immunological, and cardiac autonomic nervous system responses. Twenty-two female water polo players were allocated into control and intensification group during 7 weeks. The swimming performance, biochemical parameters, heart rate variability, profile of mood states, and upper respiratory tract infection symptoms were assessed twice before and twice after 2 weeks of intensification period. F-OR showed a worsening in total time of the repeated sprint ability (RSA) test compared with the control group and the acute fatigue group after intensification ( p ≤ 0.035). Furthermore, after the tapering period, the F-OR group maintained worse total time of the RSA test than the acute fatigue group ( p = 0.029). In addition, the acute fatigue group showed improvement in total time of the RSA test after intensification compared with the control group ( p < 0.001). No significant interactions were found for the other parameters. Therefore, periods of intensification without the F-OR development can promote higher gains in the total time of the RSA test after intensification and tapering period.

Distinct components of cardiovascular health are linked with age-related differences in cognitive abilities

Cardiovascular ageing contributes to cognitive impairment. However, the unique and synergistic contributions of multiple cardiovascular factors to cognitive function remain unclear because they are often condensed into a single composite score or examined in isolation. We hypothesized that vascular risk factors, electrocardiographic features and blood pressure indices reveal multiple latent vascular factors, with independent contributions to cognition. In a population-based deep-phenotyping study (n = 708, age 18–88), path analysis revealed three latent vascular factors dissociating the autonomic nervous system response from two components of blood pressure. These three factors made unique and additive contributions to the variability in crystallized and fluid intelligence. The discrepancy in fluid relative to crystallized intelligence, indicative of cognitive decline, was associated with a latent vascular factor predominantly expressing pulse pressure. This suggests that higher pulse pressure is associated with cognitive decline from expected performance. The effect was stronger in older adults. Controlling pulse pressure may help to preserve cognition, particularly in older adults. Our findings highlight the need to better understand the multifactorial nature of vascular aging.

Methods for eliciting and measuring behavioral and physiological consequences of stress and uncertainty in virtual reality

Military operations are characterized by high levels of stress and uncertainty, and these states can influence cognitive and physical performance outcomes. These states, however, can be difficult to reliably induce in laboratory contexts, making it challenging to quantify and model their influences on perceptual and cognitive processes underlying performance on applied tasks. Herein we describe the development and validation of a novel scenario-based virtual reality methodology, the decision making under uncertainty and stress (DeMUS) scenario, that accomplishes four primary goals. First, it induces physiological and biochemical stress responses through a threat of shock manipulation. Second, it induces transient states of uncertainty by manipulating stimulus clarity in a perceptual decision-making task. Third, it generates several performance metrics regarding recognition memory, spatial orienting, threat classification, and marksmanship decision making. Finally, the task combines behavioral, physiological, and biochemical measures to provide a more comprehensive understanding of how stress and uncertainty influence applied task performance. To provide an initial validation of the scenario and its associated tasks and measures, we conducted a pilot study (n= 18) involving stress induction and cognitive performance assessment. Analyses revealed that: 1) the DeMUS scenario elicited tonic and phasic biochemical (salivary alpha amylase and cortisol) and physiological (heart rate, pupil diameter) stress responses, 2) the scenario elicited variable sympathetic autonomic nervous system and hypothalamic-pituitary adrenal (HPA) axis responses, and 3) stress influenced some measures of memory and decision-making in both negative and positive directions. Continuing research will assess individual- and group-level predictors of performance on these virtual reality tasks, and emerging performance enhancement techniques that can help military personnel sustain performance during stressful operations.

Uterine activity modifies the response of the fetal autonomic nervous system at preterm active labor.

The autonomic nervous system of preterm fetuses has a different level of maturity than term fetuses. Thus, their autonomic response to transient hypoxemia caused by uterine contractions in labor may differ. This study aims to compare the behavior of the fetal autonomic response to uterine contractions between preterm and term active labor using a novel time-frequency analysis of fetal heart rate variability (FHRV). We performed a case-control study using fetal R-R and uterine activity time series obtained by abdominal electrical recordings from 18 women in active preterm labor (32-36 weeks of gestation) and 19 in active term labor (39-40 weeks of gestation). We analyzed 20 minutes of the fetal R-R time series by applying a Continuous Wavelet Transform (CWT) to obtain frequency (HF, 0.2-1Hz; LF, 0.05-0.2Hz) and time-frequency (Flux0, Flux90, and Flux45) domain features. Time domain FHRV features (SDNN, RMSSD, meanNN) were also calculated. In addition, ultra-short FHRV analysis was performed by segmenting the fetal R-R time series according to episodes of the uterine contraction and quiescent periods. No significant differences between preterm and term labor were found for FHRV features when calculated over 20 minutes. However, we found significant differences when segmenting between uterine contraction and quiescent periods. In the preterm group, the LF, Flux0, and Flux45 were higher during the average contraction episode compared with the average quiescent period (p<0.01), while in term fetuses, vagally mediated FHRV features (HF and RMSSD) were higher during the average contraction episode (p<0.05). The meanNN was lower during the strongest contraction in preterm fetuses compared to their consecutive quiescent period (p=0.008). The average autonomic response to contractions in preterm fetuses shows sympathetic predominance, while term fetuses respond through parasympathetic activity. Comparison between groups during the strongest contraction showed a diminished fetal autonomic response in the preterm group. Thus, separating contraction and quiescent periods during labor allows for identifying differences in the autonomic nervous system cardiac regulation between preterm and term fetuses.

Verification of Therapeutic Effects When an Occupational Therapist Walks with a Patient with Moderate Alzheimer’s-Type Dementia: A Case Report—Validity of Clinical Observational Perspective Verified by Changes in Autonomic Nervous System Responses: A Preliminary Study

Verification of Therapeutic Effects When an Occupational Therapist Walks with a Patient with Moderate Alzheimer’s-Type Dementia: A Case Report—Validity of Clinical Observational Perspective Verified by Changes in Autonomic Nervous System Responses: A Preliminary Study

Effects of Equine Interaction on Mutual Autonomic Nervous System Responses and Interoception in a Learning Program for Older Adults

Effects of Equine Interaction on Mutual Autonomic Nervous System Responses and Interoception in a Learning Program for Older Adults

Clinical application of photobiomodulation therapy to reduce the severity of acute pain after septoplasty

The purpose of the study: to evaluate the effectiveness of photobiomodulation (PBM) in the early postoperative period after septoplasty. Materials and methods: 62 patients have undergone septoplasty under general anaesthesia. Among them, there were 40 men and 22 women from 18 to 44 years of age. After septoplasty, the nasal cavity was tamponaded with foam tampons in glove rubber. The patients were divided into two groups of 31 participants, with the equal number of men and women in each of them. Patients of group 2 underwent PBM in 3 hours, 6 hours and 24 hours after septoplasty. The emitter heads generated infrared pulsed laser radiation of 0.890 microns wavelength and the power of 10 W. The emitter heads were installed for 2 minutes in the projection of the lateral cartilage and large cartilage of the nasal wing on both sides. In 48 hours after the operation, nasal swabs were removed in patients of both groups. In group 2, intranasal PBM therapy with a nozzle was performed in the continuous, modulated mode of operation in the red optical range, with the wavelength of 0.63 microns and radiation power of 8 mV for 2 minutes. Ultra-low frequency (ULF), hight frequency (HF), low frequency (LF), and total heart rate variability (HRV) power were evaluated, as well as the pain syndrome. Results. ULF was significantly lower in group 2 (8086±3003 msec2), compared to group 1 (18580±2067 msec2) (p&lt;0.001). LF was significantly higher in group 1 (1871±405 msec2), compared to group 2 (1095±190 msec2) (p&lt;0.005). In group 2, HF was lower – 1157±220 msec2 versus 1630±263 msec2 in group 1 (p&lt;0.01). In group 2, the total HRV power was also lower (13498±3226 msec2) than in group 1 (26808±2371 msec2) (p&lt;0.001). In the first three hours after the septoplasty, pain intensity did not differ between the groups. In group 2, pain decrease was observed after 6 hours, compared to the previous period (p&lt;0.05). The pain continued to decrease in both groups, and 48 hours after septoplasty, patients either did not feel pain, or it was minimal and did not cause obvious discomfort. At the same time, in the period from 6 to 24 hours after septoplasty, patients who did not undergo PBM experienced significantly higher pain syndrome than patients with PBM (p&lt;0.001). Conclusion. The use of PBM therapy with nasal tamponade after septoplasty helps to reduce pain severity as well as an inflammatory response to the surgical stress and, consequently, leads to less pronounced changes in the autonomic nervous system in response to the surgery.

Comprehensive rehabilitation of patients after septoplasty

The aim of the work was to evaluate the effectiveness of the use of photobiomodulation therapy (PBMT) in combination with Respiro Mirtol forte in order to improve the rehabilitation period of patients after septoplasty. 92 patients underwent septoplasty under general anesthesia (55 men and 37 women, age ranged from 18 to 46 years), followed by tamponade of the nasal cavity. Patients of the 1st group did not undergo PBMT; in patients of the 2nd group, PBMT was performed 3 hours, 6 hours and 24 hours after septoplasty (infrared pulsed laser radiation, λ= 0.890 μm, P = 10 W, 2 minutes in the projection of the wings of the nose ); Patients of the 3rd group were given PBMT in the indicated regimen and Rispiro Mirtol forte 5 days before and within 10 days after septoplasty. In 48 hours, after removing the tampons, in patients of the 2nd and 3rd groups, intranasal PBMT was used with a nozzle in the red range, with λ = 0.63 μm, P = mW, for 2 minutes. Heart rate variability (HRV) was assessed: ultra-low frequencies (ULF), high frequencies (HF), low frequencies (LF) and total power of heart rate variability (HRV), pain syndrome. ULF, LF, HF, total HRV power were significantly lower in group 2, compared with group 1, but higher than in group 3. In the period from 6 to 24 hours after septoplasty, the patients of the 1st group experienced a pain syndrome of greater intensity than the patients of the 2nd and 3rd groups (p &lt;0.001). The patients of the 3rd group had minimal pain values compared to the 2nd group. Thus, the use of PBMT in combination with Respiro Myrtol forte in the postoperative period after septoplasty against the background of nasal tamponade helps to minimize pain, reduce inflammation in the area of surgical damage, and, consequently, less pronounced changes in the autonomic nervous system in response to surgical stress.

Effects of acute resistance exercise with different loads on appetite, appetite hormones and autonomic nervous system responses in healthy young men

Although the effect of continuous aerobic exercise on the appetite has been widely explored, the influence of resistance exercise (RE) with different variables, including training loads, training volume, and inter-set rest, on appetite responses requires further investigation. This study examined the importance of training load in RE-induced appetite regulation, with the total training volume and inter-set rest equalized. In total, 11 healthy young men (age = 23 ± 2 years, body mass index = 22 ± 2 kg/m2) were included. Participants completed 3 trials, namely moderate-load RE (MOD; 4 sets of 8 repetitions at 85% 8RM), low-load RE (LOW; 4 sets of 15 repetitions at 45% 8RM), and a control (CON; no exercise), in a randomized, crossover design. Subjective appetite ratings; concentrations of ghrelin, peptide YY (PYY), and lactate; and the autonomic nervous system activity were evaluated before exercise and 1 h after exercise. The hunger and predicted food consumption ratings, and ghrelin concentrations immediately after exercise were significantly lower in the MOD and LOW trials (p < 0.05 vs. CON). The PYY and lactate concentrations immediately after exercise were significantly higher in the MOD and LOW trials (p < 0.05 vs. CON). Heart rate variability recovery was slower in the MOD trial. These findings suggest that both moderate-load and low-load RE at equal training volumes and inter-set rest induce similar responses on hunger suppression and orexigenic signals, except for the slower recovery of autonomic modulation after moderate-load RE. Our results suggest that when individuals aim to potentiate appetite suppression after a bout of RE, both moderate- and low-load RE could be applied.

Can nociception monitors be used to titrate remifentanil with a stable low noxious stimulation response index (NSRI)?

Purpose: Opioids blunt autonomic nervous system (ANS) responses to noxious stimuli. Nociception monitors analyze the same ANS responses and thus might prove useful to guide opioid dosing. However, concomitantly administered hypnotics also blunt ANS responses and may thus jeopardize the usefulness of nociception monitors to guide intra-operative opioid dosing. We therefore studied the PK (prediction probability) of 3 nociception monitors (NOL index, qNOX and SPI) for the prevailing opioid concentration while maintaining the NSRI (noxious stimulus response index) at a low constant value with a range of opioids and inhaled agent combinations. Methods: In 24 consenting ASA I-II patients undergoing robotic assisted radical prostatectomy, anesthesia was maintained with desflurane in O2/air and remifentanil (target controlled infusion). During the dissection phase, the remifentanil effect site concentration (Ce) in each patient was maintained at 1, 3, or 5 ng/mL for 20 min while the end-expired desflurane concentration (FET) was adjusted to keep the noxious stimulus response index (NSRI) at 5; the sequence in which each patient received each of the three remifentanil Ce was randomized. After stabilization, during each 20 min study period, the following data were collected: NSRI, NOL Index, SPI, qNOX, and FETdes. For each parameter, the prediction probability (PK) for Ce remifentanil was calculated. Results: All patients remained hemodynamically stable. Surgery was finished before the last data collection period in 5 patients with a remifentanil Ce = 5 ng/mL, and in 1 patient with a remifentanil Ce = 1 ng/mL. All other data have been included in the data analysis. The prediction probability (PK) calculated for NOL Index, qNOX and SPI for Ce remifentanil was 0.519, 0.470, and 0.477, respectively. Conclusion: Nociception monitoring becomes useless to titrate opioids when the concomitantly administered hypnotic is adjusted to maintain a low NSRI, presumably because suppression of movement to laryngoscopy also ensures suppression of the sympathetic nervous system response to the noxious stimulus present during intra-abdominal resection of the prostate. Both the hypnotic/opioid ratio and stimulus intensity of the stimulus/response pair need to be considered when attempting to use nociception to guide opioid administration.

Atypical Response to Affective Touch in Children with Autism: Multi-Parametric Exploration of the Autonomic System.

This study aimed at evaluating the autonomic response to pleasant affective touch in children with Autism Spectrum Disorders (ASD) and age-matched typically developing (TD) peers, thanks to multiple autonomic nervous system (ANS) parameters and by contrasting CT (C-tactile fibers) high- vs. low-density territory stimulations. We measured pupil diameter, skin conductance, and heart rate during gentle stroking of two skin territories (CT high- and low-density, respectively, forearm and palm of the hand) in thirty 6-12-year-old TD children and twenty ASD children. TD children showed an increase in pupil diameter and skin conductance associated with a heart rate deceleration in response to tactile stimulations at the two locations. Only the pupil was influenced by the stimulated location, with a later dilation peak following CT low-density territory stimulation. Globally, ASD children exhibited reduced autonomic responses, as well as different ANS baseline values compared to TD children. These atypical ANS responses to pleasant touch in ASD children were not specific to CT-fiber stimulation. Overall, these results point towards both basal autonomic dysregulation and lower tactile autonomic evoked responses in ASD, possibly reflecting lower arousal and related to social disengagement.