The Role of Mutations on HLA Genes in Lambert-Eaton Myasthenic Syndrome

Lambert-Eaton myasthenic syndrome (LEMS) is a rare presynaptic disorder of neuromuscular transmission in which quantal release of acetylcholine (ACh) is impaired, causing a unique set of clinical characteristics, which include proximal muscle weakness, depressed tendon reflexes, posttetanic potentiation, and autonomic changes. [1] The initial presentation can be similar to that of myasthenia gravis (MG), but the progressions of the 2 diseases have some important differences. LEMS disrupts the normally reliable neurotransmission at the neuromuscular junction (NMJ). This disruption is thought to result from an autoantibody-mediated removal of a subset of the P/Q-type Ca2+ channels involved with neurotransmitter release.

Sex-Related Differences in Polygraphic Parameters in a Population of Patients with Obstructive Sleep Apnea Syndrome

Background: Sex-related differences in the prevalence and clinical presentation of Obstructive Sleep Apnea Syndrome (OSAS) have been widely documented. The aim of this study was to investigate the influence of patients’ sex on polygraphic parameters with particular attention to sleep autonomic changes in a population of OSAS patients. Methods: Sixty OSAS patients aged 55-65 years (30 men, 30 women) were enrolled. Sleep quality was assessed with the Pittsburgh Sleep Quality Index (PSQI) and daytime sleepiness with the Epworth Sleepiness Scale (ESS). The presence of respiratory events and autonomic changes during the night was investigated by polygraphy. Results : Similar main cardiovascular risk factors prevalence was observed in both men and women. We observed a significant difference in PSQI (higher in women, p=0.0001) and ESS (higher in men, p=0.004) scores. Snoring (p=0.033), supine AHI (p=0.004), T90 (p=0.021), LO2 (p=0.0001), LF/HF ratio and LF (p=0.0001) were significantly higher in men. Sex differences in PSQI mean score and LF/HF ratio variability were preserved in all the subgroups of OSA severity. Conclusion: The influence of sex in modulating cardiovascular risk is a widely discussed topic. In our study, men showed more severe polygraphic parameters and an increase in LF/HF ratio compared to women. The results of our investigation suggest the relevance of delivering information about the different expressions of OSAS in men and women in order to improve diagnostic skills and in-depth prevention approaches.

Mechanisms of Music Impact: Autonomic Tone and the Physical Activity Roadmap to Advancing Understanding and Evidence-Based Policy

Research demonstrates that both music-making and music listening have an ability to modulate autonomic nervous system activity. The majority of studies have highlighted acute autonomic changes occurring during or immediately following a single session of music engagement. Several studies also suggest that repeated music-making and listening may have longer-term effects on autonomic tone—the prevailing balance of sympathetic vs. parasympathetic activity. Autonomic imbalance is associated with a range of neurodegenerative and neurodevelopmental disorders, mental health conditions and non-communicable diseases. Established behavioral interventions capable of restoring healthy autonomic tone (e.g., physical activity; smoking cessation) have demonstrated remarkable efficacy in broadly promoting health and preventing disease and up to 7.2 million annual deaths. Accordingly, this article proposes that music’s suggested ability to modulate autonomic tone may be a key central mechanism underpinning the broad health benefits of music-making and listening reported in several recent reviews. Further, this article highlights how physical activity research provides a relevant roadmap to efficiently advancing understanding of music’s effects on both autonomic tone and health more broadly, as well as translating this understanding into evidence-based policy and prescriptions. In particular, adapting FITT—Frequency, Intensity, Timing, Type—criteria to evaluate and prescribe music-making and listening in observational and intervention studies has excellent prospective utility.

Quantitative assessment of the relationship between behavioral and autonomic dynamics during propofol-induced unconsciousness

During general anesthesia, both behavioral and autonomic changes are caused by the administration of anesthetics such as propofol. Propofol produces unconsciousness by creating highly structured oscillations in brain circuits. The anesthetic also has autonomic effects due to its actions as a vasodilator and myocardial depressant. Understanding how autonomic dynamics change in relation to propofol-induced unconsciousness is an important scientific and clinical question since anesthesiologists often infer changes in level of unconsciousness from changes in autonomic dynamics. Therefore, we present a framework combining physiology-based statistical models that have been developed specifically for heart rate variability and electrodermal activity with a robust statistical tool to compare behavioral and multimodal autonomic changes before, during, and after propofol-induced unconsciousness. We tested this framework on physiological data recorded from nine healthy volunteers during computer-controlled administration of propofol. We studied how autonomic dynamics related to behavioral markers of unconsciousness: 1) overall, 2) during the transitions of loss and recovery of consciousness, and 3) before and after anesthesia as a whole. Our results show a strong relationship between behavioral state of consciousness and autonomic dynamics. All of our prediction models showed areas under the curve greater than 0.75 despite the presence of non-monotonic relationships among the variables during the transition periods. Our analysis highlighted the specific roles played by fast versus slow changes, parasympathetic vs sympathetic activity, heart rate variability vs electrodermal activity, and even pulse rate vs pulse amplitude information within electrodermal activity. Further advancement upon this work can quantify the complex and subject-specific relationship between behavioral changes and autonomic dynamics before, during, and after anesthesia. However, this work demonstrates the potential of a multimodal, physiologically-informed, statistical approach to characterize autonomic dynamics.

Challenges during Electroconvulsive Therapy—A Review

Electroconvulsive therapy (ECT) is one of the most successful treatment techniques employed in psychiatric practice. ECT is usually administered as a last resort to a patient who fails to respond to medical management or on an urgent basis as a life-saving procedure when immediate response is desired. It is performed under general anesthesia and is often associated with autonomic changes. All attempts should be made to minimize the resulting hemodynamic disturbances in all the patients using various pharmacological methods. Anesthesiologists providing anesthesia for ECT frequently encounter patients with diverse risk factors. Concurrent cardiovascular, neurological, respiratory, and endocrine disorders may require modification of anesthetic technique. It is ideal to optimize patients before ECT. In this review, the authors discuss the optimization, management, and modification of anesthesia care for patients with various cardiac, neurological, respiratory, and endocrine disorders presenting for ECT to improve the safety of the procedure. It is not infrequent that an anesthesiologist also plays an important role in inducing a seizure. Proconvulsants such as caffeine, adjuvants like opioids, hyperventilation, and appropriate choice of anesthetic agent for induction such as etomidate or ketamine can help. The use of BIS monitoring to guide the timing of electric stimulation is also elaborated in this review.

A Predictive Model for Emotion Recognition Based on Individual Characteristics and Autonomic Changes

Introduction: The importance of individual differences in the problem of emotion recognition has been repeatedly stated in the studies. The major concentration of this study was the prediction of heart rate variability (HRV) changes due to affective stimuli from the subject characteristics. These features were age (A), gender (G), linguality (L), and sleep (S) information. In addition, the most potent combination of individual variables (like gender and age (GA) or age, linguality, and sleep (ALS)) in the estimation of emotional HRV was explored. Methods: To this end, HRV indices of 47 college students exposed to images with four emotional categories, including happy, sad, afraid, and relaxed were analyzed. Then, a novel predictive model was introduced based on the regression equation. Results: The results showed distinctive emotional situations provoke the importance of different individual variable combinations. Generally, the most satisfactory variable arrangement in the prediction of HRV changes due to affective provocations was LS, GL, GA, ALS, and GALS. However, considering each subject separately, these combinations were changed. Conclusion: In conclusion, the suggested simple model is effective in offering new insight into the emotion studies regarding subject characteristics and autonomic parameters.

NEUROPHARMACOLOGICAL STUDY OF PHYLLANTHUS NIRURI IN SWISS ALBINO MICE

Objective: The objective of this study is to evaluate the neurological, behavioral, and autonomic changes of Phyllanthus niruri in Swiss albino mice using Irwin’s method. Methods: A total of 24 mice was divided into four groups of six each (3-male, 3-female in each group). Aqueous extract of P. niruri was prepared. Based on body weight aqueous extract was given to the mice by orally through gavage tube (Group I – 300 mg/kg, Group II – 600 mg/kg, Group III – 900 mg/kg, and Group IV – 1200 mg/kg). Neuropharmacological profile is studied for each mice using Irwin’s observational test, the mice were observed for 4 h after oral administration for various behavioral, neurological, and autonomic changes at 0, 1, 2, 3, 4 h. Results: P. niruri showed negligible actions at 300 mg/kg and 600 mg/kg body weight. At 900 mg/kg and 1200 mg/kg P. niruri showed certain behavioral and neuronal changes. P. niruri increased alertness, stereotypy, restlessness, irritability/aggressiveness in behavioral profile indicating that the drug is a CNS stimulant. Furthermore, it showed mild tremors in neurological profile indicating CNS excitation. Conclusion: Aqueous extract of P. niruri at 900 mg/kg and 1200 mg/kg showed changes in behavioral profile, neurological profile, showing it as CNS stimulant properties. Since it is an observational study further research should be done to explore CNS stimulant properties in various in vivo studies.

Development of a Classical Conditioning Task for Humans Examining Phasic Heart Rate Responses to Signaled Appetitive Stimuli: A Pilot Study

Cardiac responses to appetitive stimuli have been studied as indices of motivational states and attentional processes, the former being associated with cardiac acceleration and latter deceleration. Very few studies have examined heart rate changes in appetitive classical conditioning in humans. The current study describes the development and pilot testing of a classical conditioning task to assess cardiac responses to appetitive stimuli and cues that reliably precede them. Data from 18 adults were examined. They were shown initially neutral visual stimuli (putative CS) on a computer screen followed by pictures of high-caloric food (US). Phasic cardiac deceleration to food images was observed, consistent with an orienting response to motivationally significant stimuli. Similar responses were observed to non-appetitive stimuli when they were preceded by the cue associated with the food images, suggesting that attentional processes were engaged by conditioned stimuli. These autonomic changes provide significant information about classical conditioning effects in humans.

Approach-Avoidance Decisions Under Threat: The Role of Autonomic Psychophysiological States

Acutely challenging or threatening situations frequently require approach-avoidance decisions. Acute threat triggers fast autonomic changes that prepare the body to freeze, fight or flee. However, such autonomic changes may also influence subsequent instrumental approach-avoidance decisions. Since defensive bodily states are often not considered in value-based decision-making models, it remains unclear how they influence the decision-making process. Here, we aim to bridge this gap by discussing the existing literature on the potential role of threat-induced bodily states on decision making and provide a new neurocomputational framework explaining how these effects can facilitate or bias approach-avoid decisions under threat. Theoretical accounts have stated that threat-induced parasympathetic activity is involved in information gathering and decision making. Parasympathetic dominance over sympathetic activity is particularly seen during threat-anticipatory freezing, an evolutionarily conserved response to threat demonstrated across species and characterized by immobility and bradycardia. Although this state of freezing has been linked to altered information processing and action preparation, a full theoretical treatment of the interactions with value-based decision making has not yet been achieved. Our neural framework, which we term the Threat State/Value Integration (TSI) Model, will illustrate how threat-induced bodily states may impact valuation of competing incentives at three stages of the decision-making process, namely at threat evaluation, integration of rewards and threats, and action initiation. Additionally, because altered parasympathetic activity and decision biases have been shown in anxious populations, we will end with discussing how biases in this system can lead to characteristic patterns of avoidance seen in anxiety-related disorders, motivating future pre-clinical and clinical research.