Mindfulness Affects the Boundaries of Bodily Self-Representation: The Effect of Focused-Attention Meditation in Fading the Boundary of Peripersonal Space.

Peripersonal space (PPS) is a dynamic multisensory representation of the space around the body, influenced by internal and external sensory information. The malleability of PPS boundaries, as evidenced by their expansion after tool use or modulation through social interactions, positions PPS as a crucial element in understanding the subjective experiences of self and otherness. Building on the existing literature highlighting both the cognitive and bodily effects of mindfulness meditation, this study proposes a novel approach by employing focused-attention meditation (FAM) and a multisensory audio-tactile task to assess PPS in both the extension and sharpness of its boundaries. The research hypothesis posits that FAM, which emphasizes heightened attention to bodily sensations and interoception, may reduce the extension of PPS and make its boundaries less sharp. We enrolled 26 non-meditators who underwent a repeated measure design in which they completed the PPS task before and after a 15-min FAM induction. We found a significant reduction in the sharpness of PPS boundaries but no significant reduction in PPS extension. These results provide novel insights into the immediate effects of FAM on PPS, potentially shedding light on the modulation of self-other representations in both cognitive and bodily domains. Indeed, our findings could have implications for understanding the intricate relationship between mindfulness practices and the subjective experience of self within spatial contexts.

Evaluation of arteriovenous fistula for hemodialysis with a new generation digital stethoscope: a pilot study.

BACKGROUND AND AIMS: The management of complications of arteriovenous fistula (AVF) for hemodialysis, principally stenosis, remains a major challenge for clinicians with a substantial impact on health resources. Stenosis not infrequently preludes to thrombotic events with the loss of AVF functionality. A functioning AVF, when listened by a stethoscope, has a continuous systolic-diastolic low-frequency murmur, while with stenosis, the frequency of the murmur increases and the duration of diastolic component decreases, disappearing in severe stenosis. These evidences are strictly subjective and dependent from operator skill and experience. New generation digital stethoscopes are able to record sound and subsequently dedicated software allows to extract quantitative variables that characterize the sound in an absolutely objective and repeatable way. The aim of our study was to analyze with an appropriate software sounds from AVFs taken by a commercial digital stethoscope and to investigate the potentiality to develop an objective way to detect stenosis. METHODS: Between September 2022 and January 2023, 64 chronic hemodialysis (HD) patients were screened by two blinded experienced examiners for recognized criteria for stenosis by Doppler ultrasound (DUS) and, consequently, the sound coming from the AVFs using a 3 M™ Littmann® CORE Digital Stethoscope 8570 in standardized sites was recorded. The sound waves were transformed into quantitative variables (amplitude and frequency) using a sound analysis software. The practical usefulness of the core digital stethoscope for a quick identification of an AVF stenosis was further evaluated through a pragmatic trial. Eight young nephrologist trainees underwent a simple auscultatory training consisting of two sessions of sound auscultation focusing two times on a "normal" AVF sound by placing the digital stethoscope on a convenience site of a functional AVF. RESULTS: In 48 patients eligible, all sound components displayed, alone, a remarkable diagnostic capacity. More in detail, the AUC of the average power was 0.872 [95% CI 0.729-0.951], while that of the mean normalized frequency was 0.822 [95% 0.656-0.930]. From a total of 32 auscultations (eight different block sequences, each one comprising four auscultations), the young clinicians were able to identify the correct sound (stenosis/normal AVF) in 25 cases, corresponding to an overall accuracy of 78.12% (95% CI 60.03-90.72%). CONCLUSIONS: The analysis of sound waves by a digital stethoscope permitted us to distinguish between stenotic and no stenotic AVFs. The standardization of this technique and the introducing of data in a deep learning algorithm could allow an objective and fast method for a frequent monitoring of AVF.

Quadrato Motor Training (QMT) is associated with DNA methylation changes at DNA repeats: A pilot study.

The control of non-coding repeated DNA by DNA methylation plays an important role in genomic stability, contributing to health and healthy aging. Mind-body practices can elicit psychophysical wellbeing via epigenetic mechanisms, including DNA methylation. However, in this context the effects of movement meditations have rarely been examined. Consequently, the current study investigates the effects of a specifically structured movement meditation, called the Quadrato Motor Training (QMT) on psychophysical wellbeing and on the methylation level of repeated sequences. An 8-week daily QMT program was administered to healthy women aged 40-60 years and compared with a passive control group matched for gender and age. Psychological well-being was assessed within both groups by using self-reporting scales, including the Meaning in Life Questionnaire [MLQ] and Psychological Wellbeing Scale [PWB]). DNA methylation profiles of repeated sequences (ribosomal DNA, LINE-1 and Alu) were determined in saliva samples by deep-sequencing. In contrast to controls, the QMT group exhibited increased Search for Meaning, decreased Presence of Meaning and increased Positive Relations, suggesting that QMT may lessen the automatic patterns of thinking. In the QMT group, we also found site-specific significant methylation variations in ribosomal DNA and LINE-1 repeats, consistent with increased genome stability. Finally, the correlations found between changes in methylation and psychometric indices (MLQ and PWB) suggest that the observed epigenetic and psychological changes are interrelated. Collectively, the current results indicate that QMT may improve psychophysical health trajectories by influencing the DNA methylation of specific repetitive sequences.

The mechanisms of selective attention in phenomenal consciousness.

In three experiments we investigated the effects of selective attention in iconic memory and fragile-visual short-term memory (VSTM), which have been related to phenomenal consciousness. We used a novel retro-cue paradigm with different delays (early vs late) and object priorities (high vs equal vs low), to investigate (a) attentional costs and benefits and the role of (b) bottom-up factors and (c) fragile-VSTM in feature-based attentional selection. Experiment 1 showed that attentional costs modulate visual maintenance at longer delays, while Experiment 2 showed that by reducing the time exposure of the memory array from 250 ms to 100 ms, as a bottom-up factor, participants were not able to select the objects based on their priorities. Finally, Experiment 3 showed that a pattern mask presented before the transfer in visual working memory, attenuates the overall performance while preserving the priority effect. The implications for phenomenal consciousness before conscious access are discussed.

Perceptual bias contextualized in visually ambiguous stimuli.

The visual appearance of an object is a function of stimulus properties as well as perceptual biases imposed by the observer. The context-specific trade-off between both can be measured accurately in a perceptual judgment task, involving grouping by proximity in ambiguous dot lattices. Such grouping depends lawfully on a stimulus parameter of the dot lattices known as their aspect ratio (AR), whose effect is modulated by a perceptual bias representing the preference for a cardinal orientation. In two experiments, we investigated how preceding context can lead to bias modulation, either in a top-down fashion via visual working memory (VWM) or bottom-up via sensory priming. In Experiment 1, we embedded the perceptual judgment task in a change detection paradigm and studied how the factors of VWM load (complexity of the memory array) and content (congruency in orientation to the ensuing dot lattice) affect the prominence of perceptual bias. A robust vertical orientation bias was observed, which was increased by VWM load and modulated by congruent VWM content. In Experiment 2, dot lattices were preceded by oriented primes. Here, primes regardless of orientation elicited a vertical orientation bias in dot lattices compared to a neutral baseline. Taken together, the two experiments demonstrate that top-down context (VWM load and content) effectively controls orientation bias modulation, while bottom-up context (i.e., priming) merely acts as an undifferentiated trigger to perceptual bias. These findings characterize the temporal context sensitivity of Gestalt perception, shed light on the processes responsible for different perceptual outcomes of ambiguous stimuli, and identify some of the mechanisms controlling perceptual bias.

Multimedia Psychotherapy: brief report of a pilot study.

INTRODUCTION: Multimedia Psychotherapy is a new form of brief psychotherapy based on narrative medicine and ethnopsychoanalytic theories, developed to help patients affected by prolonged grief disorder (ICD-11). It consists of eight sessions, during which an 'audio-video memory object' is produced by using pictures, video clips, and music chosen by the bereaved patient. The audio-video montage is focused on remembering the deceased relative and help the patient to move on. Considering initial positive results, we ran a first controlled pilot study comparing experimental and control group. METHODS: We enrolled a sample of bereaved patients who were referred for prolonged grief disorder (ICD-11) by their general practitioners or psychiatrists. Patients were randomly assigned to the experimental group (n=18) or to the control group (n=18). Patients in the experimental group received psycho-pharmacological therapy and multimedia psychotherapy, while patients in the control group received psycho-pharmacological therapy and psycho-oncological support. All patients were assessed with Minnesota Multiphasic Personality Inventory-2 (MMPI-2) and Prolonged Grief-13 (PG-13) prior to beginning treatment (pre-treatment), and with PG-13 after six months from the end of the treatment (post-treatment). RESULTS: Patients in the experimental group (i.e., Multimedia Psychotherapy treatment) after six months performed better than patients in the control group in Criteria B, D, and E of PG-13 (i.e.: Separation Distress, Cognitive, Emotional, and Behavioral Symptoms, Functional Impairment). DISCUSSION: We will discuss our results, issues related to the screening of patients (due to possible contraindications of Multimedia Psychotherapy), and methodological limitations. Finally, we will discuss new future applications in other clinical situations. CONCLUSIONS: These findings suggest that multimedia psychotherapy may hold promise for the treatment of prolonged grief disorder (ICD-11).

Beneficial Effects of Mindfulness-Based Stress Reduction Training on the Well-Being of a Female Sample during the First Total Lockdown Due to COVID-19 Pandemic in Italy.

The global pandemic caused by COVID-19 and the subsequent lockdown have been widely recognized as traumatic events that pose threats to psychological well-being. Recent studies reported that during such traumatic events, women tend to be at greater risk than men for developing symptoms of stress, anxiety, and depression. Several studies reported that a mindfulness-based stress reduction protocol (MBSR) provides useful skills for dealing with traumatic events. In our study, a sample of Italian females received an 8-week MBSR course plus 6 weeks of video support for meditation practice during the first total lockdown in Italy. We assessed the participants with questionnaires before and after this period to investigate their mindfulness skills, psychological well-being, post-traumatic growth, and psychological flexibility. After the intervention, the meditators group reported improvement in measures associated with self-acceptance, purpose in life, and relation to others compared to the control group. Furthermore, our results showed that participants with greater mindfulness scores showed high levels of psychological flexibility, which in turn was positively associated with higher levels of psychological well-being. We concluded that the MBSR could support psychological well-being, at least in female subjects, even during an unpredictable adverse event, such as the COVID-19 lockdown, by reinforcing key psychological aspects.

Increased circulating Cathepsin-K levels reflect PTH control in chronic hemodialysis patients.

BACKGROUND: Mineral bone disease (MBD) is remarkably frequent among chronic hemodialysis (HD) patients. In this setting, deranged PTH levels portend an adjunctive risk of worsen outcomes. Various evidence exists demonstrating that PTH strongly induces Cathepsin-K, a cysteine protease mainly found in lysosomes of osteoclasts and macrophages which promotes bone and extracellular matrix remodelling. Cathepsin-K levels are altered in various bone disorders, systemic inflammation and even in non-advanced CKD. In this study, we tested the hypothesis of an association between Cathepsin-K, uremic-MBD and circulating PTH levels in a cohort of chronic HD patients. METHODS: We measured Cathepsin-K in 85 stable chronic HD patients and dialysis vintage > 6 months by a commercially available ELISA kit and we collected routine clinical parameters, including intact PTH. Patients were further stratified according to their "on- target" or "off-target" PTH status. RESULTS: Cathepsin-K levels were significantly higher in HD patients than in healthy controls (p < 0.0001) and were independently associated with alkaline phosphatase (ß = 0.37; p < 0.001), PTH (ß = 0.30; p = 0.02) and C-reactive protein (ß = 0.24; p = 0.008) levels. Cathepsin-K was also higher in patients with off-target PTH as compared to those with controlled PTH levels (230 [40-420] vs. 3250 [820-4205] pg/mL; p < 0.0001). At ROC analyses, Cathepsin-K levels were able to identify off-target PTH and parathyroidectomized patients (AUCs 0.85 [95% CI 0.71-0.98] and 0.97 [95% CI 0.92-0.99], respectively). CONCLUSION: In chronic HD patients, Cathepsin-K associates with PTH levels, raising the intriguing hypothesis that this protein represents a causal link between mineral and inflammatory complications and could be tested as a candidate biomarker of MBD severity and PTH balance.

Cathepsin-K is a potential cardiovascular risk biomarker in prevalent hemodialysis patients.

PURPOSE: Cardiovascular (CV) disease remains the leading cause of mortality among end-stage kidney disease (ESKD) patients. Cathepsin-K (CatK), a small cysteine protease involved in bone and extracellular matrix remodeling, has recently emerged as a key-factor in the pathogenesis of various conditions predisposing to CV disease, including atherosclerosis, obesity, diabetes, and vascular calcification. In this pilot prospective study, we aimed at evaluating the clinical significance and the predictive power of CatK in a small cohort of hemodialysis (HD) patients. METHODS: Cathepsin-K was measured in 54 prevalent HD patients and in 30 controls together with routine parameters. Patients were then followed up to 26 months and the time of cardiovascular death (endpoint of the study prospective phase) recorded. RESULTS: CatK levels were increased in the HD cohort as compared with controls (p < 0.001). In HD patients, CatK was also independently correlated to PTH (ß = 0.368; p = 0.001), alkaline phosphatase (ß = 0.383; p < 0.001), C-reactive protein (ß = 0.260; p = 0.01), and white cell count (ß = - 0.219; p = 0.02). After baseline assessment, patients were followed for CV death (mean follow-up 24.8 ± 3.1 months). Kaplan-Meier analysis showed a worsen survival (log-rank p = 0.04) in HD patients with CatK levels > 440 pg/mL (best ROC-derived cut-off with 69.6% sensitivity and 79.8% specificity) with a crude HR (Mantel-Haenszel) of CV death of 3.46 (95% CI 1.89-13.44). CONCLUSIONS: In prevalent HD patients, altered CatK levels may reflect mineral dysmetabolism and inflammation, and predict CV death in the mid-term. These preliminary findings prompt the rationale for further investigations on larger cohorts to validate CatK as a biomarker for improving CV risk stratification in ESKD.

Utility of Blood Flow/Resistance Index Ratio (Qx) as a Marker of Stenosis and Future Thrombotic Events in Native Arteriovenous Fistulas.

Objective: The resistance index (RI) and the blood flow volume (Qa) are the most used Doppler ultrasound (DUS) parameters to identify the presence of stenosis in arteriovenous fistula (AVF). However, the reliability of these indexes is now matter of concern, particularly in predicting subsequent thrombosis. In this study, we aimed at testing the diagnostic capacity of the Qa/RI ratio (Qx) for the early identification of AVF stenosis and for thrombosis risk stratification. Methods: From a multicentre source population of 336 HD patients, we identified 119 patients presenting at least one "alarm sign" for clinical suspicious of stenosis. Patients were therefore categorized by DUS as stenotic (n = 60) or not-stenotic (n = 59) and prospectively followed. Qa, RI, and QX, together with various clinical and laboratory parameters, were recorded. Results: Qa and Qx were significantly higher while RI was significantly lower in non-stenotic vs. stenotic patients (p < 0.001 for each comparison). At ROC analyses, Qx had the best discriminatory power in identifying the presence of stenosis as compared to Qa and RI (AUCs 0.976 vs. 0.953 and 0.804; p = 0.037 and p < 0.0001, respectively). During follow-up, we registered 30 thrombotic events with an incidence rate of 12.65 (95% CI 8.54-18.06) per 100 patients/year. In Cox-regression proportional hazard models, Qx showed a better capacity to predict thrombosis occurrence as compared to Qa (difference between c-indexes: 0.012; 95% CI 0.004-0.01). Conclusions: In chronic haemodialysis patients, Qx might represent a more reliable and valid indicator for the early identification of stenotic AVFs and for predicting the risk of following thrombosis.

Visual Attention Modulates Phenomenal Consciousness: Evidence From a Change Detection Study.

The distinction between phenomenal and access consciousness has been influential in the field of consciousness studies. Both Block and Lamme proposed that access consciousness, or narrow cognitive accessibility, is related to a limited capacity working memory, and that phenomenal consciousness, or broad cognitive accessibility, is related to iconic memory or, more recently, to a fragile (intermediate) short-term memory store with a larger capacity than working memory. They have also highlighted the preattentive nature of phenomenal consciousness and of the related iconic and fragile visual short-term stores, thus selectively linking attention with access consciousness, in line with Baars and Dehaene, among others. However, a range of electrophysiological and neurophysiological studies suggest that visual attention can affect early responses of neurons in visual cortex, before conscious access. Furthermore, some theories and neurocomputational models suggest earlier attentional biases related to phenomenal consciousness. To solve this controversy, and to shed light on the relationships of attention with iconic memory and subsequent stages of visual maintenance, we conducted an experiment with a novel procedure of change detection based on delayed cueing of the target for report with high- and low-priority objects marked by color. In line with our hypothesis, the results show an attentional bias toward high-priority objects in the memory array with the longer (600 and 1,200 ms) cueing delays associated with a fragile (intermediate) visual short-term memory, but not with the shorter cueing delays (16.6 and 200 ms) associated with iconic memory. These findings therefore suggest two stages of phenomenal consciousness before access consciousness: a first preattentive stage related to iconic memory and a second stage related to fragile visual short-term memory intermediate between iconic and visual working memory, which is modulated by visual attention in a time-dependent manner. Finally, our results suggest the dissociation between a mid-level visual attention modulating phenomenal consciousness and a central attention directing access consciousness.

[Possible role of Lercanidipine in Chiloperitoneum occurrence in CAPD: a case-report].

Chylous ascites is rarely observed in patients undergoing peritoneal dialysis Here, we present the occurrence of chyloperitoneum in a peritoneal dialysis patient disappeared immediately after discontinuation of calcium-antagonist.