Reactive Heart Rate Variability and Cardiac Entropy in Children with Internalizing Disorder and Healthy Controls Abstract Atypical vagal reactivity has been linked to internalizing psychopathology and less adaptive emotion regulation, but reactive cardiac entropy is largely unexplored. Therefore, this study investigated reactive vagally-mediated heart-rate variability (vmHRV) and cardiac entropy in relation to emotion regulation. Electrocardiograms of 32 children (9–13 years) with internalizing difficulties and 25 healthy controls were recorded during a baseline and a sad film. Reactivity-measures were calculated from the root mean square of successive differences (RMSSD) and sample entropy (SampEn). Emotion regulation was assessed using the emotion regulation checklist (ERC). Determinants of reactive SampEn and RMSSD were analyzed with marginal and generalized linear models. The study also modeled the relationship between cardiac reactivity and emotion regulation while controlling for psychopathology. The two groups differed significantly in vmHRV-reactivity, with seemingly higher vagal-withdrawal in the control group. SampEn increased significantly during the film, but less in subjects with higher psychopathology. Higher reactive entropy was a significant predictor of better emotion regulation as measured by the ERC. Internalizing subjects and controls showed significantly different vmHRV-reactivity. Higher reactive cardiac entropy was associated with lower internalizing psychopathology and better emotion regulation and may reflect on organizational features of the neurovisceral system relevant for adaptive emotion regulation.

Biofeedback Therapies for Chronic Insomnia: A Systematic Review Abstract The treatment of insomnia is still a challenge in clinical practice. This systematic review of randomized and quasi-randomized clinical trials aims to summarize the evidence for the use of biofeedback techniques in the treatment of chronic insomnia. Studies that compared biofeedback with other techniques of cognitive behavioral therapy, placebo, or absence of treatment were selected. The outcomes evaluated included sleep onset latency, total sleep time, sleep fragmentation, sleep efficiency and subjective sleep quality. Comparing to placebo and absence of treatment, some studies suggest possible benefits from the use of biofeedback for chronic insomnia in decreasing sleep onset latency and number of awakenings; however, there was marked divergence among included studies. There was no evidence of improvement in total sleep time, sleep efficiency and subjective sleep quality. Moreover, the maintenance of long-term benefits lacks evidence for any outcome. In the majority of outcomes evaluated, no significant differences in the effectiveness of biofeedback compared with other cognitive behavioral therapy techniques were observed. This systematic review found conflicting evidence for the effectiveness of biofeedback techniques in the treatment of chronic insomnia. Inter- and intra-group clinical heterogeneity among studies could be a reasonable explanation for the divergent results. These findings emphasize the need of performing further randomized clinical trials of higher methodological quality in order to better delineate the effectiveness of biofeedback on chronic insomnia treatment.

Social Context and Sex Moderate the Association Between Type D Personality and Cardiovascular Reactivity Abstract Type D personality has been consistently associated with adverse cardiovascular health with atypical cardiovascular reactions to psychological stress one plausible underlying mechanism. However, whether this varies by sex and social context has received little attention. This study examined the interaction between Type D personality, sex and social context on cardiovascular reactivity to acute stress. A sample of 76 healthy undergraduate students (47 female) completed the DS14 Type D measure, before undergoing a traditional cardiovascular reactivity protocol. The social context of the laboratory environment was manipulated to create a social and non-social context using a between-subjects design. Systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) were monitored throughout. No associations were evident for blood pressure. However, a significant personality × sex × social context interaction on HR reactivity was found; here Type D was associated with a higher HR response to the social task amongst males but not females, while Type D females typically exhibited blunted reactions. While these atypical reactions indicate a possible psychophysiological pathway leading to adverse cardiovascular events amongst Type Ds, it appears that Type D males are particularly vulnerable to socially based stressors, exhibiting exaggerated cardiovascular reactions.

Update on Sexual Dimorphism in Brain Structure–Function Interrelationships: A Literature Review Abstract A remarkable feature of the human brain is its sexual dimorphism. While it is well documented that the sexual dimorphism in brain structure and function exists, its clinical implications in healthy individuals as well as in those who suffer from various neuropsychiatric disorders remain to be further explored. The present paper aims to provide an overview of the remarkable features and the fundamental characteristics of the sexual dimorphism in brain performance along with clinical implications based on the review of the relevant meta-analyses published up-to-date. The primary aim is to highlight and discuss the synthesized results to advance human knowledge in the area of applied psychophysiology and support direct future interdisciplinary research efforts towards improvements in health and quality of life with regard to sexual dimorphism in brain structure–function interrelationships. The review also seeks to advance clinical management approaches to sexually dimorphic neurocognitive conditions. Better understanding of the areas implicated in sex-biased neuropsychiatric disorders can help to improve sex-specific referrals, diagnosis and proactive care management of the patients and achieving treat-to-target goals.

Heart Rate Variability, Cortisol and Attention Focus During Shamatha Quiescence Meditation Abstract Cardiac vagal tone can be seen as a stable marker for the ability to sustain attention and regulate emotion, two factors associated with the quality of meditation. In this study, heart rate variability (HRV) has been monitored in different forms of Shamatha quiescence meditation: three breath meditations, Settling the Mind in its natural state, Awareness of Awareness, Loving-kindness and Tonglen. Establish and test a practical means of monitoring neurobiological effects of meditation. Over 6 weeks, two experimental groups practiced Shamatha meditation on a daily basis (n = 20). HRV patterns and cortisol tests were monitored at three measuring points during these weeks, and an attention focus test was performed at the start and after 6 weeks. Six weeks of regular practice in Shamatha meditation were associated with HRV indices suggesting improvements in the homeostatic regulation of the autonomic nervous system (ANS) in 85% of the HRV recordings (tachogram and frequency specter) of all 20 subjects. Further, a substantial decrease in cortisol levels was also noted. The attention focus test showed a significant increase of 18.7% in sustained attention, moving from medium to high attention focus, with a significant result of t(20) = − 8.764 and p < 0.001. Participants reported positive subjective changes in attention focus, sense of happiness and calmness and increased abilities in emotional regulation and attunement. Six weeks of regular practice in Shamatha meditation contributes to a substantial increase of attention focus and a decrease in stress levels evidenced in changes in diurnal cortisol measures. HRV biofeedback shows that the sympathetic nervous system is counterbalanced by increased vagal tone, and autonomic balance is enhanced by all Shamatha meditations, not only breath meditations, but also mind meditations: Settling the Mind in its natural state, Awareness of Awareness, Loving-kindness and Tonglen. Although these results are promising, further research is recommended with HRV biofeedback instruments to report statistical analysis and to understand unique HRV patterns in Shamatha mind meditation.

Self-Regulated Force and Neuromuscular Responses During Fatiguing Isometric Leg Extensions Anchored to a Rating of Perceived Exertion Abstract The purpose of the study was to examine the fatigue-related patterns of responses for electromyography (EMG), mechanomyography (MMG), and force during a sustained isometric muscle action anchored to RPE = 5. Ten men (22.9 ± 2.0 year) performed maximal voluntary isometric contractions (MVIC) prior to and following an isometric leg extension muscle action, which was sustained for a maximal time-limit of 5 min or until it could not be maintained at RPE = 5 (actual time-limit). EMG amplitude (AMP), EMG mean power–frequency (MPF), MMG AMP, MMG MPF, and force values were determined every 5% of the actual time-limit. Regression analyses were used to examine the neuromuscular parameters and force responses, and a t test was used to examine MVIC. The pretest MVIC (62.4 ± 14.3 kg) was significantly (p < 0.001; d = 1.07) greater than posttest (47.9 ± 12.8 kg). The percent decline in force during the sustained isometric muscle action was 47.5 ± 19.6%, and there was a significant, negative force versus time relationship (p < 0.001; R = − 0.980). There was a significant, negative EMG AMP versus time relationship (p < 0.001; R = -0.789), but no significant (p > 0.05) relationships for EMG MPF, MMG AMP, or MMG MPF versus time. The findings indicated that it was necessary to reduce force and EMG AMP to maintain RPE = 5. We hypothesize that the maintenance of RPE = 5 was initially accomplished by an anticipatory feedforward mechanism and then continuous integrations of afferent feedback, which resulted in reductions of EMG AMP and force, due to reductions in neural drive, to attenuate the impact of metabolic byproducts.

Z-Score Neurofeedback and Heart Rate Variability Training for Adults and Children with Symptoms of Attention-Deficit/Hyperactivity Disorder: A Retrospective Study Abstract ADHD is a common condition that causes suffering for those affected and economic loss for society at large. The current standard treatment for ADHD includes stimulant medications, which are not effective for all patients, may include side effects, and can be non-medically misused. Z-score neurofeedback (NFB) and heart rate variability (HRV) biofeedback are alternative treatment strategies that have been associated with Attention-Deficit/Hyperactivity Disorder (ADHD) symptom improvement. We utilized a retrospective pre-post study design to quantify the change in clients’ ADHD symptoms after combined NFB + HRV treatment (which included simultaneous z-score training at four sites). We also assessed whether relevant physiological measures changed in accordance with the protocol, which would be consistent with effective NFB + HRV training. Adults (n = 39) and children (n = 100) with Borderline or Clinical ADHD classifications by the Achenbach System of Empirically Based Assessment (ASEBA) received 30 sessions of NFB + HRV training. Measures were compared before and after treatment for the ASEBA, the Integrated Visual and Auditory Continuous Performance Test (IVA), ADHD medication use, HRV and breathing parameters, and quantitative electroencephalogram (QEEG) parameters. Average ASEBA Attention-Deficit/Hyperactive Problems score improved after treatment for adults and children (p < 0.0001), with Cohen effect sizes (dz) of −1.21 and −1.17, respectively. 87.2% of adults and 80.0% of children experienced improvements of a magnitude greater than or equal to the Minimal Clinically Important Difference. After treatment, 70.8% of adults and 52.8% of children who began in the ASEBA Clinical range, and 80.0% of adults and 63.8% of children who began in the ASEBA Borderline range, were classified in the Normal range. IVA scores also improved after treatment. Changes in HRV and breathing pattern after treatment were consistent with the protocol. QEEG parameters after treatment were closer to the age-based normative mean, which is consistent with effective z-score NFB training.

The Efficacy of Neurofeedback for Pediatric Epilepsy Abstract Approximately 470,000 children (birth to 18 years old) are affected by Epilepsy (CDC in Epilepsy. https://www.cdc.gov/epilepsy/index.html, 2018). Since the initial findings in the 1970s, Sensorimotor Rhythm (SMR) has been continuously utilized for the treatment of seizures. Studies have consistently demonstrated that SMR reduces the frequency and severity of seizure activity. Although a mix of pediatric cases, adolescents and adults have been sampled in previous studies, no age effects have been reported. There continues to be a lack of research in the area of neurofeedback for the treatment of epilepsy in the pediatric population. To date, no randomized control trial specific to pediatric epilepsy has been published. The existing research regarding the use of neurofeedback in the treatment of epilepsy provides strong evidence that neurofeedback training might be an effective treatment for pediatric epilepsy. However, existing studies are not specific to the pediatric population. Moreover, there is a lack of rigor in the studies in which the effects of neurofeedback in children and adolescents with epilepsy are documented. Therefore, based on the current literature, there is not enough evidence to state that neurofeedback is efficacious for the treatment of pediatric epilepsy. However, the APBB criteria for evidence-based practices indicate that neurofeedback for pediatric epilepsy is Possibly Efficacious (Level 2). Future research in which a randomized controlled trial approach is utilized will greatly help to increase support for the use of neurofeedback as an efficacious treatment for epilepsy.

The Effect of Cultural Differences in Psychophysiological Stress Response in High Education Context: A Pilot Study Abstract The simulation scenarios are increasingly being used to assess professional competences in health sciences at university level. The objective of this study was to explore the effect of differences in the stress psychophysiological response of Psychology degree students from Spain and Colombia undergoing to clinical practice. Multiple psychophysiological measures were obtained in a sample of 25 Colombian and Spanish Psychology students undergoing to simulation scenario. Differences in the initial level of stress and habituation process as reported by self-reported and psychophysiological measurements as discussed. Differences in stress-related psychological traits are also analyzed and further discussed.

Pilot Study of Subject Education and Oximetry as They Affect Comfort During Slow-Paced Breathing Abstract This study examined the effects of subject education and oximetry on discomfort sometimes associated with slow-paced breathing (dyspnea). This study was performed because some people report anxiety about getting sufficient oxygen while breathing slowly. Clinical experience suggested that reassuring subjects unaccustomed to slow-paced breathing that they are receiving enough oxygen may lead to greater comfort. The study had a sample size of 20 sequentially randomized healthy adults constituting two groups of 10 subjects. Both groups underwent 5 min of video-guided paced breathing at a rate of six breaths per minute. One group was able to view oximetry and hear an educational script, and the other received neither the educational script nor the viewable oximetry. Subjects answered a questionnaire about ease and adequacy of respiration as well as comfort. Analysis of the questionnaire showed that the group who received education about oximetry and viewed an oximeter during training felt significantly greater comfort during slow breathing than the conventional paced breathing group (p < 0.01). While further study is warranted, these preliminary findings suggest the potential need for this dyspneic effect to be taken into account in clinical practice as well as in research.