Archivio Istituzionale della Ricerca - Università degli Studi di Pavia
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Mapping Musical Rhythm in the Brain: Causality, Connectivity, and Individual Differences
No full textRhythm is not only something we perceive but also something we internalize and feel. In music, humans have a remarkable ability to extract a regular beat from complex auditory patterns. Unlike many sensory phenomena, rhythmic processing does not rely on a direct mapping between sound features and the resulting percept. Instead, it is driven by internal, top-down mechanisms that generate and sustain a sense of temporal regularity. The motor system, particularly the premotor cortex (PMC), is hypothesized to orchestrate these processes, not only during overt synchronization but also during passive listening and imagery. Despite this, the causal role, topographical specificity, and connectivity of the PMC in beat-based timing remain poorly understood, and little is known about how individual traits and contextual factors shape rhythmic processing. This thesis addresses these gaps by combining behavioral and neurophysiological approaches to examine the causality, topography, excitability, and connectivity of the PMC in rhythm perception and imagery, while also considering the influence of individual and contextual factors in driving rhythmic processing. In Study 1, online TMS revealed that stimulation of the right caudal dorsal PMC (dPMC), compared to SMA, pre-SMA, and left dPMC, selectively disrupted beat perception. This provided causal evidence for a functional specialization of the right dPMC in endogenous beat generation, with individual differences in musical reward sensitivity further predicting perception performance. Study 2 extended these findings to imagery: right dPMC stimulation impaired beat imagery, particularly in individuals with lower auditory imagery skills, supporting its predictive role in internally guided beat processing and showing that the neural response to TMS is shaped by individual functional states. Again, musical reward sensitivity modulated rhythmic imagery performance. In Study 3, we combined TMS with electroencephalography (EEG) to investigate dPMC excitability and connectivity. Preliminary results indicated that neural excitability in the dPMC increased when perceived or imagined metric expectations were stronger, highlighting dPMC role in generating top-down predictive signals. Extending beyond perception and imagery, Study 4 investigated interpersonal rhythm production. We observed that synchronization between pairs was closer in time when they jointly produced consonant chords, with stronger consonance effect in dyads who reported lower social closeness prior to the experiment. Together, these studies provide converging evidence for the critical role of the right dPMC in beat perception and imagery, clarify its functional interactions with auditory regions, and demonstrate that rhythmic abilities are shaped not only by stable traits (e.g., reward sensitivity, imagery ability) but also by transient contextual factors (e.g., musical consonance, social closeness). More broadly, this work advances our understanding of the neural foundations of rhythm and offers insights into how predictive motor–auditory mechanisms may have supported the evolution of human musicality and its social functions
The Laurencia Stereochemical Paradox: Chemical Shift Litmus Test, Asymmetric Total Synthesis, and Structural Reassignment of (+)-Itomanallene B
No full textRed algae of the genus Laurencia are prolific sources of halogenated C15-acetogenins, many of which contain a tetrahydrofuran (THF) ring and a bromoallene terminus. Among them, Itomanallene B-type metabolites have presented a stereochemical paradox, as Laurencia intricata and Laurencia nangii yield epimeric structures despite sharing the same planar connectivity. In this study, we demonstrate that the chemical shift of the diagnostic C-4 proton provides a rapid and reliable indicator of the relative orientation (α,α′-syn vs α,α′-anti) of the THF side chains. Comparative analysis of reported NMR data reveals that anti configurations exhibit systematically more deshielded C-4 proton resonances than their syn counterparts. Applying this “chemical-shift litmus test” shows that Itomanallene B 1 from L. intricata possesses an α,α′-anti arrangement, whereas the metabolite previously reported as Itomanallene B 3 from L. nangii is instead the α,α′-syn epimer, 4-epi-Itomanallene B. This reassignment was unambiguously confirmed through the total asymmetric synthesis of the (aS,4S,6R,7R) stereoisomer of (+)-Itomanallene B, whose NMR data matched those of the natural product. The simplicity and diagnostic power of the C-4 proton chemical-shift approach provide an efficient tool for the stereochemical assignment of THF-containing C15-acetogenins, addressing a recurrent source of structural misinterpretation within the Laurencia genus
Sustainable Synthesis of Food-Grade Emulsifiers from Waste Cooking Oil via Enzymatic Glycerolysis in a Green Solvent System
No full textA Vision-Based marker-less measurement system for Real-Time Estimation of Human Body Inertial properties
No full textAccurate real-time estimation of the inertial properties of the human body is essential in biomechanics, human–robot interaction, and immersive environments. Traditional methods based on wearable markers or sensors suffer from drawbacks such as invasiveness and signal drift. This work introduces a vision-based, marker-less system for real-time estimation of the human body's inertial parameters, specifically the center of mass and inertia tensor. A multi-camera 2D setup is employed to reconstruct the 3D human posture using 13 key-points extracted via 2D human pose estimation model. A simplified geometric model discretizes the body into basic volumetric shapes, allowing analytical computation of segment-level inertial properties, while ensuring real-time compatibility. The pipeline runs on a desktop system (Intel Core i9-13900HX and NVIDIA RTX 4090). Evaluation on the Human3.6M dataset shows a mean processing time of 15.5 ms per frame. Experimental validation was performed on 15 healthy participants using a load cell-equipped platform during five predefined motor tasks. The system estimated the torque generated by the subject around the fixed axis of rotation of the instrumented platform, corresponding to the hinge axis of the force plate, with a median mean absolute error of 5.88 Nm and a median Pearson correlation coefficient of 0.98. A Monte Carlo analysis propagated measurement uncertainty from keypoint localization and body mass through the model. The resulting standard deviations were below 6.12 mm for center of mass position and below 0.095 kg m2 for inertia tensor components resulting consistent across tasks and subjects. Overall, the proposed method provides physically-coherent human body inertial properties estimation without markers, wearables, or subject-specific calibration. Its non-invasiveness, computational efficiency, and adaptability make it suitable for real-time motion analysis in clinical, ergonomic, and robotic contexts
Do early intervention services for psychosis maintain their effects after transition to usual/modular care? A systematic review and meta‐analysis
No full textEarly intervention services (EIS) for psychosis have demonstrated superiority to usual care/modular care (UC/MC) until the end of their delivery. However, the maintenance effects of EIS care after transition to UC/MC are less clear. We aimed to compare these effects vs. UC/MC at least one year after the end of EIS care. This PRISMA and MOOSE-compliant systematic review searched PubMed, EMBASE, PsycINFO and Web of Science databases and Cochrane Central Register of Reviews, without time or language restrictions. We included studies initially designed as randomized controlled trials (RCTs) comparing EIS vs. UC/MC in patients with early-phase psychosis, in which both the intervention and control groups were followed for at least 12 months after cessation of EIS care in the intervention group. Co-primary outcomes were psychiatric hospitalization, duration of hospitalization, and drop-out at the end of follow-up (preferably 5 years post-EIS initiation). Secondary outcomes were severity of total, positive and negative symptoms; quality of life, work involvement, remission, legal offences, antipsychotic use, and suicide attempts. We meta-analyzed six RCTs with data from 13 papers, including 1,416 individuals (mean age: 23.9 years, females: 36.7%). After 2-3 years of receiving UC/MC, subsequent to 2-3 years of EIS care or UC/MC, individuals who originally received EIS care spent less days hospitalized than those continuing UC/MC (n=5, standardized mean difference, SMD=0.128, 95% CI: 0.019-0.237, p=0.021). However, although we confirmed the superiority of EIS care to UC/MC at the end of the intervention period (except for work involvement and legal offences), the two groups did not differ significantly at 2-3 years post-EIS care regarding hospitalization, all-cause drop-out, quality of life; severity of total, positive and negative symptoms; work involvement, remission, legal offences, antipsychotic use, and suicide attempts. In summary, EIS care did not maintain its superiority over UC/MC 2-3 years after its cessation across meta-analyzable outcomes, except for duration of hospitalizations. These results support the need to further develop and potentially extend full or individualized EIS delivery
AUT-MENU Project: A Bicentric Intervention Study to Improve the Meal Acceptance of Subjects with Autism Spectrum Disorder
No full textBackground/Objectives: Individuals with Autism Spectrum Disorder (ASD) often exhibit low dietary diversity due to Food Selectivity (FS), leading to various forms of malnutrition, such as obesity and/or micronutrient deficiencies. The main objective of the AUT-MENU project is to improve meal acceptance among individuals with ASD. A secondary goal is to evaluate the effectiveness of a nutrition education course for parents of enrolled participants to reduce FS. Methods: The study is a bicentric intervention conducted in three care centers (Northern area, Pavia and Milan) and one secondary school (Southern area, Rome), involving individuals with ASD aged 3 to 35 years. The study consists of an observational phase (T0) and an intervention phase (T1). At T0, biographical data, clinical characteristics, and dietary patterns of participants are collected. Based on T0 findings and existing nutritional recommendations for ASD individuals, targeted menus are developed and tested. At T1, the same assessment tools used at T0 will be applied to evaluate intervention effects. Additionally, a nutrition education course for caregivers will be implemented between T0 and T1, with a pre- and post-course knowledge questionnaire to assess its effectiveness. Results: This paper reports the results from the care centers in the Northern Area. Conclusions: Menu adaptations, developed according to individual preferences and nutritional guidelines, did not significantly modify food consumption but were well tolerated, allowing for an improvement in the nutritional profile of meals without reducing acceptability. These findings support the feasibility of implementing tailored menu strategies in collective catering for individuals with ASD