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Biology subjects

Scilingo, E. P.

Publications and source records attributed to Scilingo, E. P..

8 recordsLinked to original sources

Longitudinal Characterization of a Novel Class of Recurrent, Stereotyped Neurophysiological Events in an Advanced Meditator

Seven EEG recordings over thirteen months revealed highly stereotyped transitions between distinct brain dynamics in an advanced meditator, providing a rare experimental window onto large-scale brain-state dynamics. We report an intensive longitudinal EEG case study of an experienced Tibetan tantric practitioner recorded across seven different measurement sessions, including concentrative and analytical meditation, three Dissolution of Elements sessions, nap, and reading sessions. Across conditions, the EEG repeatedly entered abrupt and reversible "ON" periods lasting tens of seconds. These periods were characterized by high-amplitude delta-theta activity, a structured 7-8 Hz component, fronto-central predominance, and a recurrent transient complex preceding state onset. Compared with matched pre- and post-event intervals, ON periods showed increased spectral power and directed connectivity, reduced relative variability, and high cross-session similarity, consistent with a recurrent and stereotyped macroscopic neurophysiological regime. Additional analyses did not support a straightforward explanation in terms of respiratory-rate changes, sleep-related variations, or overt movement artifacts. During Dissolution of Elements meditation event counts were consistent with the reported structure of the practice. However, given the current state of knowledge about the phenomenon, there is insufficient evidence to establish a close association with either the type of meditation session or the specific practices undertaken during the practitioners many years of retreat. We therefore distinguish the robust observation of a recurrent EEG regime from the more tentative hypothesis that it is related to advanced tantric meditative practice. What does appear to be well documented, however, is an unusual, abrupt, and reversible large-scale EEG reconfiguration in a deeply phenotyped expert volunteer, highlighting the value of intensive longitudinal single-participant designs for identifying and characterizing rare neurophysiological phenomena.

neuroscience↗

Physiologically Informed PCA-Partial Correlation for highly Collinear Brainstem fMRI Networks

Functional connectivity (FC) approaches from resting-state fMRI (rs-fMRI) are amply spread to investigate the cortical organization, yet the brainstem remains relatively underexplored despite its pivotal roles in both physiological and pathological conditions. The highly collinear network, in which the strongly interconnected nodes and the widespread neuromodulatory influences induce indirect or mediated interactions, make the estimation of direct brainstem FC challenging. Standard bivariate methods fail to recover the true network structure in such complex topologies, causing false positive interactions. On the other hand, partial correlation can potentially estimate the direct FC, but multicollinearity issues and collider-induced spurious correlations limit its application in high-dimensional scenarios. Here, we propose a physiologically informed framework in which the conditioning strategy for partial correlation estimation is tailored for the investigation of the brainstem and its direct interactions within the network and with whole-brain regions. Specifically, we employed a PCA-regularized partial correlation (PCA - {rho}PC) approach, where PCA is applied to the brainstem covariates to mitigate multicollinearity and model shared modulatory variance. We show that PCA - {rho}PC improves the robustness and interpretability of brainstem FC, yielding sparser and more physiologically plausible connectomes compared with conventional (regularized) approaches. Both simulation and real fMRI data raise the possibility that Pearsons and PCA-regularized approaches may complement each other in an effort to unravel the pattern of direct vs. indirect effects in highly collinear settings, paving the way for future extensions in a wide range of multivariate neuroimaging applications.

bioengineering↗

Shared book reading promotes experience-dependent autonomic synchrony in parent-preterm infant dyads

Preterm birth is associated with alterations in early caregiver-infant regulation, with potential consequences for socio-emotional and physiological development. However, the mechanisms through which early interactional experience shapes these processes remain unclear. Here, we tested whether a structured dyadic intervention could modify co-regulatory dynamics across physiological, behavioral, and relational levels. Fifty-four 7-month-old preterm infants and their parents were assigned to either a shared book reading intervention (n = 22) or an active control condition based on a shared building activity (n = 32) and compared with 39 full-term infants. The intervention consisted of an 8-week program of shared book reading, designed to structure parent-infant interaction. Physiological synchrony was assessed at the dyadic level, alongside infants autonomic regulation and cardiovascular signal complexity. Behavioral engagement and parental attachment representations were also evaluated. Results showed that mother-infant physiological synchrony emerged selectively within the interactional context trained by the intervention and only in the intervention group. This context-specific synchrony was accompanied by modulation of vagal activity and increased cardiovascular complexity in preterm infants, consistent with enhanced flexibility of autonomic control. At the behavioral and relational levels, intervention infants showed increased initiating joint attention, while parents reported higher secure attachment. These findings support a model of experience-dependent early synchrony, in which repeated dyadic interaction through shared book reading shapes the coupling between interpersonal coordination and individual physiological regulation. By linking synchrony, autonomic flexibility, and social engagement, this study identifies a mechanism through which early caregiving experience can organize developmental trajectories following prematurity.

developmental biology↗

The volatile fatty-acid fingerprint of human fear

Human axillary odour can convey information about emotional state, but the molecular composition of fear related volatile emissions remains undefined. Here, we combine low background dual chamber axillary sampling, synchronous real time and offline mass spectrometry, chemical domain group independent component analysis and hierarchical Bayesian modelling to identify a molecular finger-print of acute fear during immersive virtual reality fear induction. In 37 healthy adults, this framework recovered five axillary volatile components associated with a continuous physiology derived fear index. The fingerprint comprised increased emissions of acetic, butyric, caproic and caprylic acids, octanal and acetone, together with decreased sulcatone, decanal, geranylacetone and citraconic anhydride. This coordinated pattern was reproducible across individuals and emerged from unsupervised chemical decomposition followed by regularised Bayesian selection, without prior biochemical constraints. Posterior predictive checks and leave one participant out refitting supported its robustness within the cohort. Its composition and directionality are consistent with sympathetic autonomic metabolic mobilisation, suggesting contributions from fatty acid handling, acetone related metabolism and axillary gland output. These findings define a candidate molecular cue of acute human fear and establish a replicable methodological template for decoding the chemical language of human emotion.

neuroscience↗

Interpersonal physiological synchrony: estimation and clinical application to cardiac dynamics of parent-infant dyads

Synchrony is a key mechanism that builds up the foundations of human interactions. Quantifying the level of physiological synchronization that occurs during dyadic exchanges is essential to fully comprehend social phenomena. We present a new index to characterize the coupling of complex physiological dynamics: the optimized Multichannel Complexity Index (opMCI). We validated this approach using synthetic time series of two coupled Henon Maps, with four different coupling levels in unidirectional and bidirectional manners. We demonstrated that the opMCI method allows to effectively discern between all coupling levels. Then, we applied the opMCI metric on heart rate variability data collected from 37 parent-infant dyads, during shared reading and playing activities, in the framework of the Shared Emotional Reading (SHER) project, with the aim of assessing the effects of early intervention in preterm babies. Two groups presented preterm infants: an intervention group, who participated in a two-month shared reading program, and a control group, who practiced shared play activities. A full-term group provided additional control data. The opMCI values were significantly higher for the intervention dyads with respect to the other groups during the shared reading task, showing that an early reading intervention program could increase parent-infant synchrony in preterm babies. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=112 SRC="FIGDIR/small/712915v2_ufig1.gif" ALT="Figure 1"> View larger version (29K): org.highwire.dtl.DTLVardef@22f13forg.highwire.dtl.DTLVardef@c623eorg.highwire.dtl.DTLVardef@10605b5org.highwire.dtl.DTLVardef@60d594_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIInterpersonal physiological synchrony is a fundamental mechanism for the evolutionary path C_LIO_LIAn ad-hoc methodological framework to assess nonlinear cardiac coupling is lacking C_LIO_LIThe opMCI has been shown to be a reliable tool for assessing the degree of synchrony C_LIO_LIEarly shared book reading may increase parent-infant synchrony in a clinical setting C_LI

bioengineering↗

Analytical meditation improves physiological well-being in expert practitioners: a study on central and peripheral neurophysiological correlates

Meditation has been long associated with improvements in mental well-being, emotional regulation, and attentional control. Yet, the diversity of meditative techniques and participant expertise has hindered the systematic identification of their neurophysiological correlates supporting these benefits. To address this challenge, we investigated the neurophysiological signatures of concentrative and analytical meditation in 35 experienced Tibetan monk practitioners. EEG, ECG, EDA, and respiration were simultaneously recorded during Concentrative, Loving-Kindness and Emptiness meditations. Linear-mixed-models revealed significant modulations in autonomic and cortical activity across meditations. Peripheral indices indicated enhanced parasympathetic tone, decreases respiratory rate, and gradual increase in EDA - reflecting a state of relaxed-alertness with concurrent vagal engagement and sustained sympathetic arousal. EEG analyses supported this state showing elevated gamma-band power during analytical meditations. These findings suggest that advanced meditative states foster an adaptive integration of autonomic and cortical responses, supporting the emergence of relaxed-vigilance - a psychophysiological condition associated with well-being and cognitive flexibility.

neuroscience↗

Cardiorespiratory mechanisms triggered during music perception in preterm infants and adults

SHORT-ABSTRACTPreterm newborns autonomic response to dynamic auditory stimuli is poorly understood. To examine how cardiac and respiratory systems adjust their rhythms in response to music, we assessed 18 preterm infants (gestational age 37.73 {+/-} 0.80 weeks) and 19 adults across music listening. Heart rate variability (HRV) dynamics and respiratory sinus arrhythmia (RSA), and cardiorespiratory coupling were analyzed. Both groups showed decreased high-frequency power in HRV during music listening. In preterm infants, RSA increased (p-value = 0.005), possibly suggesting a state of calm alertness, where the infant is physiologically prepared for interaction with environmental stimuli, while adults had decreased RSA (p-value = 0.003) and concomitant increased values of the low frequency/high frequency power ratio, possibly reflecting heightened alertness. While HRV responses to music were similar between preterms and adults, only the investigation of RSA and cardiorespiratory coupling measures revealed the delicate balance of autonomic dynamics in preterm newborns.

physiology↗

Use of Bioelectric Impedance Analysis (BIA) as a new method to detect prostate cancer

BackgroundTo determine the accuracy of a novel BIA test endorectal probe. MethodsOne hundred-forty consecutive patient candidates to prostate biopsy and 40 healthy volunteers were selected (NCT03428087). Total PSA and PSA density (PSAD) determinations, digital rectal examination (DRE), and the BIA test were analysed in patients and controls. A 16 cores trans rectal prostate biopsy was performed on all patients with clinical suspicion of PCa after a multiparametric MRI (mMRI) test. The study endpoints were to determine accuracy of BIA test in comparison to PSA, PSAD levels, and mMRI and obtain PCa prediction in candidates to prostate biopsy by BIA test. The Mann-Withney U test, the Wilkoxon rank test, and Holm-Bonferronis method were adopted for statistical analyses, and a computational approach was also applied to differentiate patients with PCa from those with benign disease (BPH). ResultsCombined DRE, TRUS, PSA, and PSAD alone failed to satisfactorily discern patients with PCa from those with BPH (62.86% of discrimination accuracy) and mMRI PIRADS [≥]3 showed a sensitivity of 83% and a specificity of 59%. The accuracy in discerning PCa and BPH increased up to 75% by BIA test (sensitivity 63.33% and specificity 83.75%). ConclusionsThe BIA test is a simple, promising, cheap, and reliable test for PCa non-invasive diagnosis. The novel finger probe may improve PCa detection also in patients with low-risk PCa, thus reducing the need of useless biopsies.

biophysics↗