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Reggente, N.

Publications and source records attributed to Reggente, N..

7 recordsLinked to original sources

Meditation Depth Enhances the Functional Signal-to-Noise Ratio of the Brain

Across contemplative traditions, depper states of meditation are described as states of heightened clarity, vividness, and stillness of mind, yet what this clarity corresponds to in the brain has remained difficult to specify. The functional signal-to-noise ratio (f-SNR) framework frames mental clarity as a measurable property of neural signals: the degree to which brain activity tracks the causes of sensory signals rather than endogenous, irrelevant, fluctuations. It predicts that deepening meditation should raise f-SNR, expressing sensory events more faithfully in neural signals against ongoing background activity. We tested this prediction across different levels of meditative depth. Twenty-nine experienced Vipassana practitioners meditated while auditory tones were presented, periodically reporting their depth of meditation. f-SNR was quantified from event-related potentials (ERPs) in a fronto-central P3 window and from single-trial decodability of auditory tone-evoked activity against no-tone background EEG. High-depth states were associated with greater ERP signal-to-noise ratio, stronger single-trial signal consistency, and improved decodability of sound tones. These results suggest that meditative depth is expressed in the reproducibility and stimulus-background separability of sensory responses, consistent with deep meditation enhancing the brains functional signal-to-noise ratio by improving the clarity of sensory signals and reducing endogenous noise.

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Contrasting Cognitive, Behavioral, and Physiological Responses to Breathwork vs. Naturalistic Stimuli in Reflective Chamber and VR Headset Environments

The MindGym, a novel immersive technology utilizing a reflective chamber environment, was developed to create standardized experiential content, including anxiolytic experiences. This study examined whether therapeutic experiences originally created in the MindGym could maintain their efficacy when delivered via 360-degree recordings through virtual reality (VR) headsets. A randomized controlled trial (N=126) compared anxiety reduction, cognitive performance, and physiological responses across four conditions: MindGym and VR platforms, each delivering either breathwork or rain stimuli. Results demonstrated significant improvements across all conditions in cognitive performance (Trail Making Test RTACC, p.fdr<.001; Architex Total Speed, p.fdr<.001) and anxiety reduction (STAI, p.fdr<.001). Breathwork conditions produced greater decreases in breath rate compared to rain stimuli (p.fdr=.002). Treatment responses were moderated by individual differences, with absorption (MODTAS) predicting both awe (p.fdr=.004) and ego dissolution (p.fdr=.015), while openness to experience interacted with stimuli type to influence anxiety reduction (p.fdr=.038). The anxiolytic effects originally generated in the MindGym maintained full efficacy when translated to VR delivery, with no significant differences in effectiveness or immersion between the original environment and its virtual reproduction. These findings establish the MindGym as a viable content creation platform for immersive, anxiety-reducing experiences that can be successfully adapted to more accessible delivery systems, while highlighting the potential for personalization based on individual differences. Future research should investigate the translation of more complex MindGym-generated experiences to expand accessible anxiety management tools.

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Alterations in large-scale resting-state network nodes following transcranial focused ultrasound of deep brain structures

BackgroundLow-intensity transcranial focused ultrasound (tFUS) is a brain stimulation approach that holds immense promise for the treatment of brain-based disorders. Several studies in humans have shown that tFUS can successfully modulate perfusion in focal sonication targets including the amygdala; however, limited research has explored how tFUS impacts the function of large-scale neural networks. ObjectiveThe aim of the current study was to address this gap and examine changes in resting-state connectivity between large-scale network nodes using a randomized, double-blind, within-subject crossover study design. MethodsHealthy adults (n=18) completed two tFUS sessions, 14 days apart. Each session included tFUS of either the right amygdala or the left entorhinal cortex (ErC). The inclusion of two active targets allowed for within-subjects comparisons as a function of the locus of sonication. Resting-state functional magnetic resonance imaging was collected before and after each tFUS session. ResultstFUS altered resting-state functional connectivity (rsFC) within and between rs-network nodes. Specifically, pre-to-post sonication of the right amygdala modulated connectivity within nodes of the salience network (SAN) and between nodes of the SAN and the default-mode network (DMN) and fronto-parietal network (FRP). A decrease in SAN to FPN connectivity was specific to the amygdala target. Pre-to-post sonication of the left ErC was found to modulate connectivity between the dorsal attention network (DAN) and FPN and DMN. An increase in DAN to DMN connectivity was specific to the ErC target. ConclusionThese preliminary findings may suggest that tFUS induces neuroplastic changes beyond the immediate sonication target.

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Multivariate Neural Patterns of Reward and Anxiety in Adolescents with Anorexia Nervosa

People with anorexia nervosa (AN) commonly exhibit elevated anxiety and atypical reward responsiveness. To examine multivariate neural patterns associated with reward and the impact of anxiety on reward, we analyzed fMRI data from a monetary reward task using representational similarity analysis, a multivariate approach that measures trial-by-trial consistency of neural responses. Twenty-five adolescent girls with AN and 22 mildly anxious controls lacking any history of AN were presented personalized anxiety-provoking or neutral words before receiving a reward, and neural response patterns in reward regions were analyzed. Consistent with our preregistered hypothesis, AN participants showed lower representational similarity than controls during neutral-word rewarded trials. Within groups, controls showed significant representational similarity in reward circuit regions including the left nucleus accumbens, left basolateral amygdala, and left medial orbitofrontal cortex, which were not observed in AN. Further, reward-related prefrontal cognitive control areas - left ventrolateral prefrontal cortex and left dorsolateral prefrontal cortex - showed significant representational similarity in both groups, but a larger spatial extent in controls. Contrary to predictions, there were no significant between-group differences for the effects of anxiety-words on reward representational similarity, and representational similarity did not predict longitudinal symptom change over six months. Overall, the results demonstrate relatively inconsistent trial-by-trial responses to reward receipt in the neutral state in AN compared with controls in both reward circuit and cognitive control regions, but no significant differential effects of anxiety states on reward responses. These results add to dynamic understandings of reward processing in AN that have potential implications for planning and guiding reward-focused interventions.

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Repeated Exposure Decreases Aesthetic Chills Likelihood but Increases Intensity

Aesthetic chills are a peak emotional response to affectively charged stimuli such as music, films, or speech. This study investigates the impact of repeated exposure on the frequency and intensity of aesthetic chills. Through a longitudinal approach, we quantified changes in chill likelihood, intensity, and pleasure across multiple exposures, focusing on audio stimuli. Participants (n = 58) were randomly exposed to 6 chill-evoking stimuli pre-validated on the population of interest, in a counterbalanced order. Our findings revealed a significant decrease in the likelihood of experiencing chills with repeated exposure, suggesting habituation to chills itself or potential fatigue in response to aesthetic stimuli. The study also identified distinct demographic and psychophysiological response patterns across different participant groups, indicating variability in chill responses. These results provide insights into the dynamic nature of aesthetic experiences and their underlying neural mechanisms, with implications for understanding emotional and reward processing in psychophysiology.

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Neural entrainment induced by periodic audiovisual stimulation: A large-sample EEG study

Stroboscopic or "flicker" stimulation is a form of periodic visual stimulation that induces geometric hallucinations through closed eyelids. While the visual effects of this form of sensory stimulation have received considerable attention, few studies have investigated the neural entrainment effects of periodic visual stimulation. Here, we introduce two variants of the classic flicker paradigm while recording EEG to study neural entrainment effects in a large sample (over 80 participants per condition). In the first condition, we used multimodal stimulation composed of two simultaneous visual strobe frequencies paired with binaural beats which provided auditory stimulation at roughly the same frequency as the slower strobe. We compared this condition to sham stimulation, in which both strobes were set to very low frequencies and in which the binaural beats were absent. Additionally, we compared both conditions to a control group in which participants focused on their breathing during eyes-closed meditation (no stimulation). Our results demonstrate powerful evidence of neural entrainment at the frequency of the slower strobe in the experimental condition. Moreover, our findings resemble effects reported in prior literature using conventional non-invasive techniques for electromagnetic brain stimulation. We argue that stroboscopic stimulation should be further developed along these lines, e.g., as a potential therapeutic technique in psychiatric disorders.

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Predicting Empathy from Resting Brain Connectivity

Recent studies suggest that individual differences in empathic concern may be mediated by continuous interactions between self-other resonance and cognitive control networks. To test this hypothesis, we used machine learning to examine whether resting fMRI connectivity (i.e. the degree of synchronous BOLD activity across multiple cortical areas in the absence of task demands) of resonance and control networks could predict trait empathy (n=58). Indeed, resonance and control networks interconnectivity predicted empathic concern. Empathic concern was also predicted by connectivity within the somatomotor network. In light of numerous reported sex differences in empathy, we controlled for biological sex and also studied separately what aspect of these features could predict participants sex. Sex was best predicted by the interconnectivity of the visual system with the resonance, somatomotor, and cingulo-opercular network, as well as the somatomotor-control network connectivity. These findings confirm that variation in empathic responses to others reflects characteristic network properties detectable regardless of task demands. Furthermore, network properties of the visual system may be a locus of sex differences previously unaccounted for in empathy research. Finally, these findings suggest that it may be possible to assess empathic predispositions in individuals without needing to perform conventional empathy assessments.

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