Biology subjects

Palyanov, A.

Publications and source records attributed to Palyanov, A..

3 recordsLinked to original sources

bioRxiv2025

Beyond Locomotion: How Specialized Motor Rhythms Enable Vertebrate Escape from Capture

Escape behaviors following capture are crucial for survival, yet their underlying neurobiological mechanisms remain poorly understood. We investigated how Xenopus laevis tadpoles use struggling movements to escape head restraint. High-speed video tracking revealed a stereotyped sequence of body flexions with distinct kinematics during capture and release. We further recorded motoneuron and motor nerve activity along the body axis during fictive struggling to reconstruct biologically realistic struggling commands, to drive the movement of a biomechanically detailed tadpole model. Simulations showed that struggling - characterized by long-duration, low-frequency, caudorostral muscle activation - was optimized to generate escape forces. Notably, hydrodynamic thrust alone proved insufficient for release. However, direct mechanical interactions between the tadpoles body and the restraining object generated additional reactive forces that facilitated escape. These findings demonstrate how animals use coordinated motor outputs and body mechanics to interact with environment to generate maximal freeing forces as the fundamental escape strategy.

neuroscience↗

bioRxiv2021

Whole animal modelling reveals neuronal mechanisms of decision-making and reproduces unpredictable swimming in frog tadpoles

Animal behaviour is based on interaction between nervous, musculoskeletal and environmental systems. How does an animal process sensory stimuli, use it to decide whether and how to respond, and initiate the locomotor behaviour? We build the whole body computer models of a simple vertebrate with a complete chain of neural circuits and body units for sensory information processing, decision-making, generation of spiking activities, muscle innervation, body flexion, body-water interaction, and movement. Our Central Nervous System (CNS) model generates biologically-realistic spiking and reveals that sensory memory populations on two hindbrain sides compete for swimming initiation and first body flexion. Biomechanical 3-dimensional "Virtual Tadpole" (VT) model is constructed to evaluate if motor outputs of CNS model can produce swimming-like movements in a volume of "water". We find that whole animal modelling generates reliable and realistic swimming. The combination of CNS and VT models opens a new perspective for experiments with immobilised tadpoles.

bioinformatics↗

bioRxiv2017

EGL-19 AND EXP-2 ION CHANNELS MODELLING WITHIN C. ELEGANS PHARYNGEAL MUSCLE CELL ALLOWS REPRODUCTION OF CA2+ DRIVEN ACTION POTENTIALS, BOTH SINGLE EVENTS AND TRAINS

One of the current problems at the interface between neuroscience, biophysics, and computational modeling is the reverse-engineering and reproduction of Caenorhabditis elegans using computer simulation. The aim of our research was to develop the computational models and techniques for solving this problem while participating in the international open science OpenWorm Project. We have suggested models of a typical C. elegans neuron and a pharyngeal muscle cell, which were constructed and optimized using the NEURON simulation environment. The available experimental data about EGL-19 and EXP-2 ion channels allowed the model of a muscle to reproduce the action potential time profile correctly. Also, the model of a neuron reproduces quite accurately the mechanism of neural signal transmission based on passive propagation. We believe our models to be promising for better representing the specifics of various nervous and muscular cell classes when adding the corresponding ion channel models. Moreover, they can be used to construct the networks of such elements.

neuroscience↗