Biology subjects

Tognetti, A.

Publications and source records attributed to Tognetti, A..

3 recordsLinked to original sources

bioRxiv2026

An image-based framework for in silico trials of ablation strategies in scar-related ventricular tachycardia

Scar-related ventricular tachycardia (VT) is sustained by patient-specific structural and functional remodeling of the ventricular substrate, and the optimal substrate-based ablation strategy remains debated. We present an image-based computational framework for conducting controlled in silico trials of VT ablation strategies. Patient-specific left ventricular electrophysiology models were generated from late gadolinium enhancement cardiac magnetic resonance images by incorporating image-derived scar, border-zone tissue with structural fibrosis, fiber orientation, and physiologically plausible Purkinje-driven sinus activation. A dedicated standalone graphical user interface was developed to perform interactive virtual ablation based on imaging-derived or simulated electrophysiological data. We implemented standardized VT reinducibility testing to compare different lesion sets in terms of residual VT inducibility and ablation burden. As a proof of concept, the framework was applied to 20 patients with ischemic or non-ischemic cardiomyopathy undergoing VT ablation. Sustained VT was inducible in 17 patients, yielding 127 sustained VT episodes and 88 unique reentrant circuits at baseline. Four substrate-based ablation strategies were compared: scar homogenization, primary deceleration-zone ablation, primary plus secondary deceleration-zone ablation, and CMR-guided scar dechanneling. All strategies significantly reduced VT inducibility compared with baseline. Scar homogenization achieved the largest reduction in residual unique sustained VTs but required the largest ablated myocardial volume. Conversely, CMR- guided scar dechanneling showed the most favorable efficiency profile by reducing VT inducibility while limiting ablated viable myocardium. The proposed framework enables quantitative comparison of ablation efficacy, ablation burden, and mechanisms of ablation success or failure in image-guided VT therapy planning.

bioengineering↗

bioRxiv2026

Precision measurement of non-conscious avoidance reactions using 3D tracking: Validation across olfaction and vision

One of our sensory systems key functions is to detect threats in the environment. Sensory information eliciting negative emotions, such as fear or disgust, triggers instinctive avoidance reactions. This core survival mechanism is believed to be expressed as subtle non-conscious postural reactions, even when participants are instructed to stand still. Such avoidance behavior has mainly been studied using indirect measures that make participants aware of their posture (e.g. force-plate based methods) or measures that depend on explicit cognitive tasks, like moving a joystick to indicate an urge to approach or avoid the stimulus; experimental tasks with limited ecological validity and generalizability. Therefore, despite the importance of this basic survival strategy, its underlying mechanisms are still poorly understood. Here, we used a novel 3D-camera-based method allowing direct but implicit measures of postural reactions with high precision. Participants are aware that they are being filmed but, crucially, are not informed that distance measures are obtained. We assessed this ecologically valid measure of approach/avoidance responses in two different sensory modalities: olfaction and vision. Participants were standing upright while exposed to either olfactory or visual stimuli and verbally rating their perceived valence in each trial. In response to subjectively unpleasant odors and images, participants moved away from the stimulus source, as compared to pleasant stimuli. These results demonstrate a putative modality-independent early proxy for avoidance behavior in response to perceived negative valence. Considering its face validity and general applicability, this novel experimental method presents new possibilities for assessing non-conscious approach-avoidance responses in humans.

neuroscience↗

bioRxiv2017

Females prefer cooperative males even when cooperative behavior is unobserved: evidence from the mound-building mouse, Mus spicilegus

Theoretical and empirical studies in humans suggest that cooperative behaviors may act as signals during mate choice. However, cooperation is not always observable by potential partners before mate choice. To address whether cooperative phenotypes are preferred based on cues different from cooperative behaviors per se, we designed an experimental paradigm using wild-born mound-building mice (Mus spicilegus), a species with biparental care. In this species, females cannot observe male cooperative behaviors: mate choice occurs in the spring, whereas mounds are cooperatively built in the fall. We first assessed the variation in mound building investment and identified males exhibiting high and low amounts of cooperation. Second, we presented these males to females during two-way choice tests. As offspring survival relies on mound protection, we hypothesized that mound building could be a form of paternal care and assessed whether cooperative males were more involved in offspring attendance using pup-retrieval experiments. Our results indicate that females were more attracted to highly cooperative males over less cooperative, even when they did not observe them build. This finding suggests that female mate choice is influenced either by cues of cooperativeness different than cooperative behaviors or by preferences for traits associated with cooperativeness. Moreover, male offspring attendance was negatively correlated with cooperativeness, suggesting the potential existence of two alternative paternal strategies in offspring care (mound building versus offspring attendance). Overall, our findings support the existence of preference for cooperative phenotypes in a non-human species and suggest that sexual selection might be involved in the evolution of cooperation.

animal behavior and cognition↗