Validation of the Italian version of the Neuroception of Psychological Safety Scale (NPSS)

Research on the neuroscience of fear in both humans and non-humans has suggested that a lack of acquisition of safety cues might be a biological hallmark of posttraumatic stress disorder (PTSD). Danger perception, and in particular, feeling as one's own life is in danger, is thought to represent a major predictor of PTSD. Persistent danger perception is concurrently associated with a persistence of lack of safety. However, despite several research efforts, no validated psychometric tools exist regarding psychological safety as a unique core construct in the domain of a soothing-contentment system. By including social, compassionate, and bodily components, the Neuroception of Psychological Safety Scale (NPSS), neurophysiologically rooted in the polyvagal theory, aims to specifically assess psychological safety. Originally developed in English, we employed a rather large non clinical sample to validate our Italian translation of the NPSS (n = 338) and the scale was found to retain a three-factor structure. In light of its positive moderate correlations with the Unconditional Self-Kindness Scale (ρ = 0.376) and the Self-Compassion Scale-Short-Form (ρ = 0.481), good convergent validity and robust psychometric properties were shown by the NPSS. The Subjective Traumatic Outlook Questionnaire (ρ = -0.283) and the three subscales of the Body Perception Questionnaire-22-Body Awareness (ρ = -0.103), Supradiaphragmatic Reactivity (ρ = -0.234), and Body Awareness/Subdiaphragmatic Reactivity (ρ = -0.146)-were found to have weak negative correlations with the NPSS, which further demonstrated its good discriminant validity. Eventually, the NPSS was found to show good test-retest reliability (intraclass correlation coefficient = 0.922; three-week time interval), and its usage is fostered in clinical and research contexts where the evaluation of psychological safety is of relevance.

Predicting postpartum depressive symptoms by evaluating self-report autonomic nervous system reactivity during pregnancy

OBJECTIVE

Altered self-reported autonomic reactivity is associated with worse mental health in the general population. Although dysfunctional changes in ANS during pregnancy have been investigated in relation to depressive symptoms, no studies addressed the relationship between self-report autonomic reactivity during pregnancy and depressive symptoms after the delivery. The present study aimed to assess the impact of prepartum self-reported autonomic reactivity on the development of postpartum depressive symptoms.

METHODS

In this longitudinal study, 170 women were assessed during pregnancy (i.e., second or third trimester) and after childbirth (i.e., one month after the delivery). Self-reported autonomic reactivity was assessed through the Body Perception Questionnaire - Short Form that evaluates the autonomic functions related to organs above (i.e., supradiaphragmatic reactivity) and below (i.e., subdiaphragmatic reactivity) the diaphragm. In addition, prepartum and postpartum depressive symptoms were evaluated using the Patient Health Questionnaire - 9.

RESULTS

Findings showed that higher prepartum supradiaphragmatic reactivity predicted higher depressive symptoms in the postpartum period (β = 0.112, p = 0.009) after controlling for prepartum depressive symptomatology and other potential covariates.

CONCLUSIONS

Evaluation of self-reported autonomic activity may be a useful tool to identify antenatally women at risk of postpartum depressive symptoms. Future studies are needed to evaluate the effectiveness of interventions aimed at reducing the threat-responsive autonomic reactivity at rest and improving adaptive autonomic regulation to prevent postpartum depression.

The vagal paradox: A polyvagal solution

Although there is a consistent literature documenting that vagal cardioinhibitory pathways support homeostatic functions, another less frequently cited literature implicates vagal cardioinhibitory pathways in compromises to survival in humans and other mammals. The latter is usually associated with threat reactions, chronic stress, and potentially lethal clinical conditions such as hypoxia. Solving this 'vagal paradox' in studies conducted in the neonatal intensive care unit served as the motivator for the Polyvagal Theory (PVT). The paradox is resolved when the different functions of vagal cardioinhibitory fibers originating in two anatomically distinguishable brainstem areas are recognized. One pathway originates in a dorsal area known as the dorsal motor nucleus of the vagus and the other in a ventral area of the brainstem known as nucleus ambiguus. Unlike mammals, in all ancestral vertebrates from which mammals evolved, cardioinhibitory vagal fibers primarily originate in the dorsal motor nucleus of the vagus. Thus, in mammals the vagus nerve is 'poly' vagal because it contains two distinct efferent pathways. Developmental and evolutionary biology identify a ventral migration of vagal cardioinhibitory fibers that culminate in an integrated circuit that has been labeled the ventral vagal complex. This complex consists of the interneuronal communication of the ventral vagus with the source nuclei involved in regulating the striated muscles of the head and face via special visceral efferent pathways. This integrated system enables the coordination of vagal regulation of the heart with sucking, swallowing, breathing, and vocalizing and forms the basis of a social engagement system that allows sociality to be a potent neuromodulator resulting in calm states that promote homeostatic function. These biobehavioral features, dependent on the maturation of the ventral vagal complex, can be compromised in preterm infants. Developmental biology informs us that in the immature mammal (e.g., fetus, preterm infant) the ventral vagus is not fully functional and myelinization is not complete; this neuroanatomical profile may potentiate the impact of vagal cardioinhibitory pathways originating in the dorsal motor nucleus of the vagus. This vulnerability is confirmed clinically in the life-threatening reactions of apnea and bradycardia in human preterm newborns, which are hypothetically mediated through chronotropic dorsal vagal pathways. Neuroanatomical research documents that the distribution of cardioinhibitory neurons representing these two distinct vagal source nuclei varies among mammals and changes during early development. By explaining the solution of the 'vagal paradox' in the preterm human, the paper highlights the functional cardioinhibitory functions of the two vagal source nuclei and provides the scientific foundation for the testing of hypotheses generated by PVT.

Divergent emotional and autonomic responses to Cyberball in patients with opioid use disorder on opioid agonist treatment

The perception of social exclusion among patients with opioid use disorder (OUD) could be affected by long-term opioid use. This study explores the emotional and cardiac autonomic responses to an experience of ostracism in a sample of participants with OUD on opioid agonist treatment (OAT). Twenty patients with OUD and twenty healthy controls (HC) performed a ball-tossing game (Cyberball) with two conditions: Inclusion and Ostracism. We measured self-reported ratings of perceived threat towards one's fundamental needs and respiratory sinus arrhythmia (RSA) immediately after the game and 10 min after Ostracism (Reflective stage). Following ostracism, participants with OUD self-reported blunted feelings of threat to the fundamental need to belong. RSA levels were significantly suppressed immediately after ostracism and during the Reflective stage in comparison with HC, indicating an autonomic alteration in response to threatening social situations. Finally, only among HC higher perceived threats towards fundamental needs predicted increases in RSA levels, suggesting an adaptive vagal regulation in response to a perceived threat. Conversely, among patients with OUD the subjective response to ostracism was not associated with the autonomic reaction. OAT may have a protective effect against negative feelings of ostracism. However patients with OUD on OAT present poor autonomic regulation in response to social threats, which could reflect their trait hypersensitivity to social rejection.

Silence and its effects on the autonomic nervous system: A systematic review

This systematic review explores the influence of silence on the autonomic nervous system. The Polyvagal Theory has been used as a reference model to describe the autonomic nervous system by explaining its role in emotional regulation, social engagement, and adaptive physiological responses. PubMed, Scopus, PsycInfo, EMBASE, and Google Scholar were systematically searched up until July 2023 for relevant studies. The literature search yielded 511 results, and 37 studies were eventually included in this review. Silence affects the autonomic nervous system differently based on whether it is inner or outer silence. Inner silence enhances activity of the ventral vagus, favoring social engagement, and reducing sympathetic nervous system activity and physiological stress. Outer silence, conversely, can induce a heightened state of alertness, potentially triggering vagal brake removal and sympathetic nervous system activation, though with training, it can foster inner silence, preventing such activation. The autonomic nervous system response to silence can also be influenced by other factors such as context, familiarity with silence, presence and quality of outer noise, and empathy.

Heart rate variability during social interaction: Effects of valence and emotion regulation

Conceptual models of psychosocial influences on short-term changes (i.e., reactivity) in vagally-mediated heart rate variability (vmHRV) emphasize self-regulatory effort and social threat versus comfort. However, these two general perspectives have been tested separately in nearly all cases, limiting conclusions about the relative importance or possible interactive effects of effortful self-regulation and social stress. The present study compared effects of effort to regulate emotional expression and social stress versus safety on vmHRV reactivity during an interpersonal interaction, in a 2 (self-regulate emotion vs. express emotion freely) × 3 (positive vs. neutral vs. negative interaction valence) × 2 (male vs. female) between-subjects randomized factorial design. A sample of 180 undergraduates (90 women; 69 % White) discussed a current events topic (i.e., human-caused climate change) with a prerecorded partner, presented as a live interaction over a computer. Self-reports of affective responses, self-regulation effort, and appraisals of the partner's behavior, as well as observer ratings of participants' behavior during the interaction, supported the effectiveness of self-regulation and interaction valence manipulations, although the former manipulation may have been somewhat weaker than the latter. Primary analyses of high-frequency heart rate variability (HF-HRV) and root mean square of successive differences (RMSSD) in heart beat intervals recorded at baseline and during the interaction revealed larger decreases in vmHRV during negative than neutral or positive interactions, but no effects of self-regulation instructions. Overall, results indicated more robust effects of social stress on vmHRV reactivity, relative to effects of self-regulatory effort.

Functional anatomy of the vagus system: How does the polyvagal theory comply?

Due to its pivotal role in autonomic networks and interoception, the vagus attracts continued interest from both basic scientists and therapists of various clinical disciplines. In particular, the widespread use of heart rate variability as an index of autonomic cardiac control and a proposed central role of the vagus in biopsychological concepts, e.g., the polyvagal theory, provide a good opportunity to recall basic features of vagal anatomy. In addition to the "classical" vagal brainstem nuclei, i.e., dorsal motor nucleus, nucleus ambiguus and nucleus tractus solitarii, the spinal trigeminal and paratrigeminal nuclei come into play as targets of vagal afferents. On the other hand, the nucleus of the solitary tract receives and integrates not only visceral but also somatic afferents.

Cardiac autonomic regulation and joint hypermobility in adolescents with functional abdominal pain disorders

BACKGROUND

Joint hypermobility (JH) is associated with autonomic nervous system dysregulation and functional abdominal pain disorders (FAPDs). Understanding the neurophysiological processes linking these conditions can inform clinical interventions. Autonomic activity regulates gastrointestinal (GI) sensorimotor function and may be a key mechanism. The aims of this study were to examine the relation of JH with dynamic autonomic activity and parasympathetic regulation in adolescents with FAPDs and identify optimal JH cutoff scores that best index autonomic regulation in FAPDs.

METHODS

A total of 92 adolescents with FAPDs and 27 healthy controls (age 8-18 years; 80% female) were prospectively enrolled. JH was assessed by Beighton scores. ECG recordings were conducted during supine, sitting, and standing posture challenges. ECG-derived variables-heart period (HP), respiratory sinus arrhythmia (RSA), and vagal efficiency (VE)-were analyzed using linear regression and mixed effects modeling.

KEY RESULTS

Beighton scores of ≥4 optimally distinguished autonomic function. Adolescents with FAPD and JH had reduced VE compared to adolescents with FAPDs without JH (B = 18.88, SE = 6.25, p = 0.003) and healthy controls (B = 17.56, SE = 8.63, p = 0.044). These subjects also had lower and less dynamic RSA and HP values during posture shifts, with strongest differences in supine position and using the VE metric.

CONCLUSIONS & INFERENCES

Suboptimal autonomic regulation indexed by reduced vagal efficiency may be a mechanism of symptoms in hypermobile FAPD patients with Beighton score ≥ 4. Autonomic disturbance may serve as potential intervention target for patients with JH and functional GI disorders.

Autonomic vulnerability to biased perception of social inclusion in borderline personality disorder

BACKGROUND

Individuals with Borderline Personality Disorder (BPD) feel rejected even when socially included. The pathophysiological mechanisms of this rejection bias are still unknown. Using the Cyberball paradigm, we investigated whether patients with BPD, display altered physiological responses to social inclusion and ostracism, as assessed by changes in Respiratory Sinus Arrhythmia (RSA).

METHODS

The sample comprised 30 patients with BPD, 30 with remitted Major Depressive Disorder (rMDD) and 30 Healthy Controls (HC). Self-report ratings of threats toward one's fundamental need to belong and RSA reactivity were measured immediately after each Cyberball condition.

RESULTS

Participants with BPD showed lower RSA at rest than HC. Only patients with BPD, reported higher threats to fundamental needs and exhibited a further decline in RSA after the Inclusion condition.

CONCLUSIONS

Individuals with BPD experience a biased appraisal of social inclusion both at the subjective and physiological level, showing higher feelings of ostracism and a breakdown of autonomic regulation to including social scenarios.

The role of the vagus nerve in fibromyalgia syndrome

Fibromyalgia (FM) syndrome is a common illness characterized by chronic widespread pain, sleep problems, fatigue, and cognitive difficulties. Dysfunctional neurotransmitter systems that influence the body's endogenous stress response systems are thought to underlie many of the major FM-related symptoms. A model of FM pathogenesis suggests biological and psychosocial variables interact to influence the genetic predisposition, but the precise mechanisms remain unclear. The Polyvagal Theory provides a theoretical framework from which to investigate potential biological mechanisms. The vagus nerve (VN) has anti-inflammatory properties via its afferent and efferent fibers. A low vagal tone (as assessed by low heart rate variability), has been observed in painful and inflammatory diseases, including FM, while the ventral branch of the VN is linked to emotional expression and social engagement. These anti-inflammatory and psychological (limbic system) properties of the VN may possess therapeutic potential in treating FM. This review paper summarizes the scientific literature regarding the potential role of the VN in transducing and/or therapeutically managing FM signs and symptoms.

Impact of hypnotic safety on disorders of gut-brain interaction: A pilot study

Functional gastrointestinal disorders, i.e., abdominal conditions without identifiable structural etiologies, are seen frequently in primary care and specialty practices. As subtle physiological processes have been identified as potential contributing factors to these functional disorders, these disorders have been recently relabeled, Disorders of Gut-Brain Interaction (DGBI). Moreover, some of these processes, e.g., sympathetic nervous system activity and inflammation, are being increasingly related to psychosocial factors such as situational stress and histories of trauma, abuse, and neglect. As the activity of the autonomic nervous system (ANS) has been long considered to be a contributory factor for DGBI, the present study utilized a theory-driven model based on the Polyvagal Theory to optimize ANS activity for the promotion of healthy digestive activity. Specifically, a hypnotic intervention to increase neuroception of safety was employed with three female college students diagnosed with functional dyspepsia and irritable bowel syndrome in a single-subject design. This intervention was found to be associated with increases in the experience of safe/warm positive affect and decreases in symptoms of functional dyspepsia and irritable bowel syndrome as well as depression and anxiety. The hypnotic intervention for the promotion of a sense of safety is recommended for the treatment of other functional somatic disorders as well as trauma-related conditions. Potential complications related to individuals with prolonged trauma and attachment issues also are reviewed.

Fetal growth restriction: From Polyvagal theory to developmental impairments?

BACKGROUND

The Polyvagal theory argues that behavioral modulation is a fundamental neurodevelopmental process that depends on autonomic regulation.

OBJECTIVE

The present study aimed to assess sleep architecture in newborns with fetal growth restriction (FGR) using polysomnography as an indicator of Polyvagal theory.

METHODS

We studied polysomnography recordings from 68 preterm infants, 34 with FGR and 34 born with appropriate growth for gestational age (AGA), who were matched according to the corrected age for prematurity (CA). Total sleep time, arousals, the percentage of quiet sleep, active sleep, indeterminate sleep, and heart rate were compared between the groups. Linear multiple regression analyses were used to evaluate polysomnography data for the FGR and AGA groups.

RESULTS

Average heart rate was significantly lower in most FGR groups compared with AGA groups, and small to large effect sizes were observed in several sleep responses when comparing these groups. In the lineal regression model the CA explains significantly the differences in heart rate, controlled by FGR (p = .012). Additionally, there was evidence that sleeping states show similar trends, that is, increases in quiet and indeterminate sleep, as well as decreases in active sleep when CA was controlled by FGR.

CONCLUSION

FGR probably intensifies the unfavorable effect of preterm birth in the responses evaluated by polysomnography. It seems that FGR is associated with alteration in sleep regulation and with differences in heart rate modulation, which may serve as a strategy to preserve energy and such differences likely underlie neurodevelopmental impairments in affected newborns.

Resting heart rate variability is negatively associated with mirror neuron and limbic response to emotional faces

Whether neurovisceral integration, reflected by resting high-frequency heart rate variability (HRV), constrains or facilitates neural reactivity to other people's emotions is unclear. We assessed the relation between resting HRV and neural activation when observing and imitating emotional faces. We focused on brain regions implicated in sensorimotor resonance, salience detection and arousal. We used electrocardiogram data to compute resting HRV. Resting HRV measures were negatively correlated with activation in a portion of the inferior frontal gyrus showing mirror neuron properties, the insula and the amygdala in response to observation, but not imitation, of emotional faces. Thus, resting HRV appears to be linked to sensitivity to others' emotional cues, both in terms of the tendency to map others' emotional facial expressions onto one's own motor system and to rapidly detect and mark others' emotions as salient events. Resting HRV may reflect, in part, a threshold for increased processing of others' emotional cues.

Respiratory sinus arrhythmia is a major component of heart rate variability in undisturbed, remotely monitored rattlesnakes, Crotalus durissus

ECG recordings were obtained using an implanted telemetry device from the South American rattlesnake, Crotalus durissus, held under stable conditions without restraining cables or interaction with researchers. Mean heart rate (f _H) recovered rapidly (<24 h) from anaesthesia and operative procedures. This preceded a more gradual development of heart rate variability (HRV), with instantaneous f _H increasing during each lung ventilation cycle. Atropine injection increased mean f _H and abolished HRV. Complete autonomic blockade revealed a cholinergic tonus on the heart of 55% and an adrenergic tonus of 37%. Power spectral analysis of HRV identified a peak at the same frequency as ventilation. This correlation was sustained after temperature changes and it was more evident, marked by a more prominent power spectrum peak, when ventilation is less episodic. This HRV component is homologous to that observed in mammals, termed respiratory sinus arrhythmia (RSA). Evidence for instantaneous control of f _H indicated rapid conduction of activity in the cardiac efferent nervous supply, as supported by the description of myelinated fibres in the cardiac vagus. Establishment of HRV 10 days after surgical intervention seems a reliable indicator of the re-establishment of control of integrative functions by the autonomic nervous system. We suggest that this criterion could be applied to other animals exposed to natural or imposed trauma, thus improving protocols involving animal handling, including veterinarian procedures.

Brain Awareness and Conflict in Veterinary Medical Practice: What Happens and How to Deal with It

Conflict resolution is a technical skill required in medical environments. This article explores interpersonal conflicts through a brain awareness lens and offers tools for increasing the ability to manage conflict in veterinary medical practice.

Transcutaneous vagus nerve stimulation (tVNS) enhances recognition of emotions in faces but not bodies

The polyvagal theory suggests that the vagus nerve is the key phylogenetic substrate enabling optimal social interactions, a crucial aspect of which is emotion recognition. A previous study showed that the vagus nerve plays a causal role in mediating people's ability to recognize emotions based on images of the eye region. The aim of this study is to verify whether the previously reported causal link between vagal activity and emotion recognition can be generalized to situations in which emotions must be inferred from images of whole faces and bodies. To this end, we employed transcutaneous vagus nerve stimulation (tVNS), a novel non-invasive brain stimulation technique that causes the vagus nerve to fire by the application of a mild electrical stimulation to the auricular branch of the vagus nerve, located in the anterior protuberance of the outer ear. In two separate sessions, participants received active or sham tVNS before and while performing two emotion recognition tasks, aimed at indexing their ability to recognize emotions from facial and bodily expressions. Active tVNS, compared to sham stimulation, enhanced emotion recognition for whole faces but not for bodies. Our results confirm and further extend recent observations supporting a causal relationship between vagus nerve activity and the ability to infer others' emotional state, but restrict this association to situations in which the emotional state is conveyed by the whole face and/or by salient facial cues, such as eyes.

From psychological moments to mortality: A multidisciplinary synthesis on heart rate variability spanning the continuum of time

Heart rate variability (HRV) indexes functioning of the vagus nerve, arguably the most important nerve in the human body. The Neurovisceral Integration Model has provided a structural framework for understanding brain-body integration, highlighting the role of the vagus in adaptation to the environment. In the present paper, we emphasise a temporal framework in which HRV may be considered a missing, structural link between psychological moments and mortality, a proposal we label as Neurovisceral Integration Across a Continuum of Time (or NIACT). This new framework places neurovisceral integration on a dimension of time, highlighting implications for lifespan development and healthy aging, and helping to bridge the gap between clearly demarcated disciplines such as psychology and epidemiology. The NIACT provides a novel framework, which conceptualizes how everyday psychological moments both affect and are affected by the vagus in ways that have long-term effects on mortality risk. We further emphasize that a longitudinal approach to understanding change in vagal function over time may yield novel scientific insights and important public health outcomes.

When rumination counts: Perceived social support and heart rate variability in daily life

Rumination and social support could modulate cardiac activity. Although both variables are somehow interrelated, they are often studied independently, and their interplay is seldom considered. We aimed to analyze the interaction of rumination and perceived social support on vagally mediated heart rate variability (HRV) in daily life. The sample consisted of 117 healthy participants (57% female, mean age = 27.9, SD = 5.5 years). Ambulatory HRV (root mean squared successive differences), respiration, body position, and body movements were recorded continuously on three consecutive weekdays. Momentary social, situational, and cognitive-affective variables (affect, ruminative thoughts, perceived social support) were assessed using a computerized diary. There was a significant interaction between momentary rumination and perceived social support on ambulatory HRV: When participants were involved in social interactions with low social support, concurrent rumination was associated with attenuated HRV. However, when rumination was accompanied by a strong sense of support, HRV significantly increased. The quality of social interactions and rumination seem to interact in daily life to predict cardiac autonomic control. The results stress the necessity to consider the interplay of psychological and social factors in order to evaluate beneficial or adverse effects on cardiac health.

A single session of meditation reduces of physiological indices of anger in both experienced and novice meditators

The goal of the present study was to explore how anger reduction via a single session of meditation might be measured using psychophysiological methodologies. To achieve this, 15 novice meditators (Experiment 1) and 12 practiced meditators (Experiment 2) completed autobiographical anger inductions prior to, and following, meditation training while respiration rate, heart rate, and blood pressure were measured. Participants also reported subjective anger via a visual analog scale. At both stages, the experienced meditators' physiological reaction to the anger induction reflected that of relaxation: slowed breathing and heart rate and decreased blood pressure. Naïve meditators exhibited physiological reactions that were consistent with anger during the pre-meditation stage, while after meditation training and a second anger induction they elicited physiological evidence of relaxation. The current results examining meditation training show that the naïve group's physiological measures mimicked those of the experienced group following a single session of meditation training.