Publications by Pavan P Ramdya

Modeling conditional distributions of neural and behavioral data with masked variational autoencoders

Pavan P Ramdya, Victor Lobato Rios, Daniel Eduardo Morales Garza

Extracting the relationship between high-dimensional neural recordings and complex behavior is a ubiquitous problem in neuroscience. Encoding and decoding models target the conditional distribution of neural activity given behavior and vice versa, while di ...

2025

Descending networks transform command signals into population motor control

Pavan P Ramdya, Jonas Friedrich Braun

To convert intentions into actions, movement instructions must pass from the brain to downstream motor circuits through descending neurons (DNs). These include small sets of command-like neurons that are sufficient to drive behaviours—the circuit mechanism ...

Springer Science and Business Media LLC2024

NeuroMechFly v2: simulating embodied sensorimotor control in adult Drosophila

Pavan P Ramdya

Discovering principles underlying the control of animal behavior requires a tight dialogue between experiments and neuromechanical models. Such models have primarily been used to investigate motor control with less emphasis on how the brain and motor syste ...

NATURE PORTFOLIO2024

The neuromechanics of animal locomotion: From biology to robotics and back

Auke Ijspeert, Pavan P Ramdya

Robotics and neuroscience are sister disciplines that both aim to understand how agile, efficient, and robust locomotion can be achieved in autonomous agents. Robotics has already benefitted from neuromechanical principles discovered by investigating anima ...

AMER ASSOC ADVANCEMENT SCIENCE2023

Ascending neurons convey behavioral state to integrative sensory and action selection brain regions

Pavan P Ramdya, Nicolas Talabot, Chin-Lin Chen, Florian Aymanns

Knowing one's own behavioral state has long been theorized as critical for contextualizing dynamic sensory cues and identifying appropriate future behaviors. Ascending neurons (ANs) in the motor system that project to the brain are well positioned to provi ...

NATURE PORTFOLIO2023

NeuroMechFly: an integrative simulation testbed for studying Drosophila behavioral control

Pavan P Ramdya, Victor Lobato Rios

NATURE PORTFOLIO2022

Connecting the dots in ethology: applying network theory to understand neural and animal collectives

Pavan P Ramdya, Adám Gosztolai

A major goal shared by neuroscience and collective behavior is to understand how dynamic interactions between individual elements give rise to behaviors in populations of neurons and animals, respectively. This goal has recently become within reach, thanks ...

CURRENT BIOLOGY LTD2022

Microengineered devices enable long-term imaging of the ventral nerve cord in behaving adult Drosophila

Pavan P Ramdya, Mahmut Selman Sakar, Chin-Lin Chen, Murat Kaynak, Semih Günel, Victor Lobato Rios, Laura Joan Hermans, Florian Aymanns, Jonas Friedrich Braun

The dynamics and connectivity of neural circuits continuously change on timescales ranging from milliseconds to an animal's lifetime. Therefore, to understand biological networks, minimally invasive methods are required to repeatedly record them in behavin ...

Nature Research2022

Descending neuron population dynamics during odor-evoked and spontaneous limb-dependent behaviors

Pavan P Ramdya, Chin-Lin Chen, Florian Aymanns

Deciphering how the brain regulates motor circuits to control complex behaviors is an important, long-standing challenge in neuroscience. In the fly, Drosophila melanogaster, this is coordinated by a population of similar to 1100 descending neurons (DNs). ...

eLIFE SCIENCES PUBL LTD2022

NeuroMechFly, a neuromechanical model of adult Drosophila melanogaster

Auke Ijspeert, Pavan P Ramdya, Jonathan Patrick Arreguit O'Neill, Shravan Tata Ramalingasetty, Victor Lobato Rios

Animal behavior emerges from an interaction between neural network dynamics, musculoskeletal properties and the physical environment. Accessing and understanding the interplay between these elements requires the development of integrative and morphological ...

NATURE PORTFOLIO2022

Overcoming the Domain Gap in Neural Action Representations

Pascal Fua, Pavan P Ramdya, Semih Günel, Florian Aymanns, Sina Honari

Relating behavior to brain activity in animals is a fundamental goal in neuroscience, with practical applications in building robust brain-machine interfaces. However, the domain gap between individuals is a major issue that prevents the training of genera ...

SPRINGER2022

LiftPose3D, a deep learning-based approach for transforming two-dimensional to three-dimensional poses in laboratory animals

Pascal Fua, Pavan P Ramdya, Helge Jochen Rhodin, Semih Günel, Victor Lobato Rios, Daniel Eduardo Morales Garza, Marco Pietro Abrate, Adám Gosztolai

LiftPose3D infers three-dimensional poses from two-dimensional data or from limited three-dimensional data. The approach is illustrated for videos of behaving Drosophila, mice, rats and macaques. ...

NATURE PORTFOLIO2021

Deformation-aware Unpaired Image Translation for Pose Estimation on Laboratory Animals

Pascal Fua, Pavan P Ramdya, Helge Jochen Rhodin, Semih Günel, Mirela Ostrek, Siyuan Li

Our goal is to capture the pose of neuroscience model organisms, without using any manual supervision, to be able to study how neural circuits orchestrate behaviour. Human pose estimation attains remarkable accuracy when trained on real or simulated datase ...

2020

Extensive and diverse patterns of cell death sculpt neural networks in insects

Pavan P Ramdya, Chin-Lin Chen

Changes to the structure and function of neural networks are thought to underlie the evolutionary adaptation of animal behaviours. Among the many developmental phenomena that generate change programmed cell death (PCD) appears to play a key role. We show t ...

2020

Serotonergic Modulation of Walking in Drosophila

Pavan P Ramdya, Chin-Lin Chen

To navigate complex environments, animals must generate highly robust, yet flexible, locomotor behaviors. For example, walking speed must be tailored to the needs of a particular environment. Not only must animals choose the correct speed and gait, they mu ...

CELL PRESS2019

DeepFly3D, a deep learning-based approach for 3D limb and appendage tracking in tethered, adult Drosophila

Pascal Fua, Pavan P Ramdya, Helge Jochen Rhodin, Semih Günel, Daniel Eduardo Morales Garza, João Henrique Campagnolo

Studying how neural circuits orchestrate limbed behaviors requires the precise measurement of the positions of each appendage in 3-dimensional (3D) space. Deep neural networks can estimate 2-dimensional (2D) pose in freely behaving and tethered animals. Ho ...

2019

Imaging neural activity in the ventral nerve cord of behaving adult Drosophila

Michaël Unser, Pavan P Ramdya, Denis Fortun, Chin-Lin Chen, Laura Joan Hermans, Florian Aymanns

To understand neural circuits that control limbs, one must measure their activity during behavior. Until now this goal has been challenging, because limb premotor and motor circuits have been largely inaccessible for large-scale recordings in intact, movin ...

Nature Research2018

Climbing favours the tripod gait over alternative faster insect gaits

Dario Floreano, Auke Ijspeert, Thibault Lucien Christian Asselborn, Pavan P Ramdya, Robin Thandiackal

To escape danger or catch prey, running vertebrates rely on dynamic gaits with minimal ground contact. By contrast, most insects use a tripod gait that maintains at least three legs on the ground at any given time. One prevailing hypothesis for this differ ...

Nature Research2017

Fluctuation-driven neural dynamics reproduce Drosophila locomotor patterns

Dario Floreano, Andrea Maesani, Pavan P Ramdya, Kyle Gustafson

The neural mechanisms determining the timing of even simple actions, such as when to walk or rest, are largely mysterious. One intriguing, but untested, hypothesis posits a role for ongoing activity fluctuations in neurons of central action selection circu ...

2015

Mechanosensory interactions drive collective behaviour in Drosophila

Dario Floreano, Lukas Frisch, Pawel Lichocki, Winnie Wing Yee Tse, Pavan P Ramdya

Collective behaviour enhances environmental sensing and decision-making in groups of animals. Experimental and theoretical investigations of schooling fish, flocking birds and human crowds have demonstrated that simple interactions between individuals can ...

2015