WHole Animal Modelling (WHAM): Toward the integrated understanding of sensory motor control in C. elegans

Lead Research Organisation: University of Leeds
Department Name: Sch of Computing

Abstract

Animals are remarkable creatures. No man-made machine even comes close in its ability to navigate complex environments, respond to rich sensory cues, learn and adapt its behaviour when encountering completely novel scenarios and much much more. But even the simplest animals, ruled by even the simplest nervous systems, can achieve this. Simple animals may not be able to play chess or balance bank statements, but there is much we can learn from them about their robust mechanisms for sensory-integration and motor control which may be of use to us in control engineering, bio-robotics and even in future brain-machine interfaces that are being developed for neuro-prosthetic applications.

An excellent starting point for understanding animal behaviour is a tiny, free living 1mm long roundworm, called C. elegans. By comparison to our 100 billion nerve cells, or even a fly's 100 thousand nerve cells, this worm's entire nervous system consists of a mere 302 nerve cells. Unlike our nervous system, the worm's circuitry is hard wired and identical across individuals of the species, making it possible to study rigorously and reproducibly. Due in part to its simplicity, and in part to its ease of manipulation in the lab, this is the only animal for which this entire nervous system has been mapped in exquisite detail (to sub-cellular resolution). But despite its relative simplicity, this worm possesses many of the functions that are attributed to more complex animals, including feeding, mating, complex sensory abilities, memory and learning. It is not surprising, therefore, that the modelling of this worm has captured the imagination of physicists, computer scientists and engineers alike. The integrated modelling of C. elegans has even been proposed as one of the UK's ``Grand Challenges for Computing Research.''

In this Fellowship, I will begin to integrate our understanding of C. elegans sensory motor behaviour in a single computational model. The challenge is to bridge the gap between the effectively static neural circuit architecture and the dynamic neural computation it sustains. This fellowship will enable me to deliver a step change, not only in our understanding of an important model organism, but also in advancing the science and engineering of complex systems, whether in the context of reverse engineering real world networks, or in the context of designing them.

Planned Impact

The research proposed will generate new understanding and models of a complex (biological) system. The outcomes will inform a number of academic disciplines, which themselves impact on a number of different application areas. This is fundamental research, so the societal and economic impacts are envisaged as long term, with quantifiable benefits being realised within 10-20 years.

The key application areas identified at present as having potential societal and economic impact are:

1. Engineering design processes - Modelling frameworks and methodologies that address difficulties inherent in complex systems may be applied in industrial applications that involve the design of complex systems. Examples could range from automated control systems (that are embedded in cars or other vehicles) to cognitive robotics (with applications for more efficient/effective manufacturing processes and autonomous robots for search and rescue, navigation in toxic or difficult environments, space exploration and biomedical applications).

2. 3D vision and imaging technologies are increasingly important in a range of applications, in particular in entertainment (films and games). This technology will almost certainly feed into education within 5-10 years. In addition, the advancement of 3D technologies may have applications in manufacturing (such as more efficient and more miniaturised automation, quality control, sorting or manipulation).

3. Medical - knowledge of the C.elegans genetics and neurobiology will enable medical researchers to tease out principles of nerve function and neurological pathologies. Such knowledge will in turn be used develop improved diagnostics and treatment. Examples are better drug therapies and improved design of brain-machine interfaces for neuro-prostheses. There would be both economic impacts to companies developing such products and societal impact to patients receiving improved treatments.

The approach taken to the modelling of a complete animal has already attracted interest from the press and public engagement is a key objective. The central idea of deriving lessons from studying animals as examples of complex adaptive systems and applying the principles and methodologies to model complex processes and organisations and to design products and systems is accessible and appealing. The improvement of understanding by the public of the complex systems approach will enrich our culture, contribute to a better awareness of the importance of University research and inform future research directions here and with collaborators. In turn, this can also be used to inform public policy.

Publications

10 25 50
 
Description We have obtained a deep understanding of how this simple animal moves (how it generates forward motion, how it steers, and how it adapts its locomotion in different environments). We have extended this study from the standard 2D environment to 3D volumes. We have also probed and identified new features of the behaviour that we could trace back to specific mechanisms, using combinations of models and experiments.

Engineering design processes - Modelling frameworks and methodologies have been developed that address difficulties inherent in complex systems. In follow up funding, we are exploring how these may be applied in industrial applications that involve the design and operation of complex systems. The computational models developed have explored (i) locomotion (ii) sensory responses (iii) sensory adaptation (iv) sensory integration (v) learning and memory and (vi) sensory-motor integration. Some of these results are summarised in the PhD theses of Tom Sanders (2016), Christopher Brittin (2018), Elpiniki Kalogeropoulou (2018) and Jack Denham (2021), in publications (see separate section) as well as papers with Thomas Ranner and Jack Denham (arXiv:1702.04988 [physics.bio-ph] 2017; https://doi.org/10.1098/rstb.2018.0208 2018; https://doi.org/10.1016/j.coisb.2018.12.002 2019 and https://doi.org/10.1523/ENEURO.0241-20.2020 in 2020). The postulated applicability of these findings is now being investigated in robotics, through follow on funding (EP/N010523/1) and through follow up collaborative projects.

3D vision and imaging technologies were developed and 3D behaviours were explored and 3D models of the animal are being developed (see Salfelder et al. VAIB2021 conference paper).

Genetic strains of C. elegans have been developed that allow us to experimentally interrogate the computational functions of different cells and circuits.
Exploitation Route The community wide effort to understand C. elegans continues and our work contributes to this effort. The mathematics and computational methods and frameworks developed are shared and available to the community, as is our experimental data.
Sectors Agriculture, Food and Drink,Construction,Digital/Communication/Information Technologies (including Software),Environment,Other

 
Description Analysing the Motion of Biological Swimmers
Amount £246,811 (GBP)
Funding ID EP/S01540X/1 
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 11/2018 
End 04/2020
 
Description BBSRC Grouped
Amount £601,388 (GBP)
Funding ID BB/E008038/1 
Organisation Biotechnology and Biological Sciences Research Council (BBSRC) 
Sector Public
Country United Kingdom
Start  
 
Description EPSRC Grand Challenge 2 - Future Cities
Amount £4,217,380 (GBP)
Funding ID EP/N010523/1 
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 01/2016 
End 12/2020
 
Description Hooke Proposal (Royal Society Discussion Meeting)
Amount £0 (GBP)
Organisation The Royal Society 
Sector Charity/Non Profit
Country United Kingdom
Start 01/2018 
End 01/2018
 
Description Pervasive Sensing for Buried Pipes
Amount £7,290,965 (GBP)
Funding ID EP/S016813/1 
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 03/2019 
End 02/2024
 
Description University of Leeds
Amount £46,393 (GBP)
Funding ID University Research Scholarship 
Organisation University of Leeds 
Sector Academic/University
Country United Kingdom
Start 01/2015 
End 12/2017
 
Description University of Leeds
Amount £48,230 (GBP)
Funding ID University Research Scholarship 
Organisation University of Leeds 
Sector Academic/University
Country United Kingdom
Start 01/2013 
End 06/2017
 
Title A multiscale brain map derived from whole-brain volumetric reconstructions 
Description This archive provides source volumetric and synaptic data, data analysis, models and modeling software for Brittin et al. (2021). 
Type Of Material Database/Collection of data 
Year Produced 2021 
Provided To Others? Yes  
Impact As of March 2022. the resources here have been viewed downloaded 250 times from this website (other mirrors exist). Multiple papers have already incorporated our data and its analysis, in particular Taylor et al. "Molecular topography of an entire nervous system" Cell (2021) https://doi.org/10.1016/j.cell.2021.06.023. 
URL https://doi.org/10.5281/zenodo.4383277
 
Title Code for running a simluation of a C. elegans locomotion 
Description Code for running a simluation of a C. elegans integrated neuro-mechanical locomotion model written in C++. The code is based on two contributions, a mechanical model from Cohen, Netta and Ranner, Thomas (2017), A new computational method for a model of C. elegans biomechanics: Insights into elasticity and locomotion performance. arXiv e-prints 1702.04988, https://arxiv.org/abs/1702.04988 and a neural circuit model from Denham, Jack E. and Ranner, Thomas and Cohen, Netta (2018), "Signatures of proprioceptive control in Caenorhabditis elegans locomotion". Philos Trans R Soc Lond B Biol Sci. 2018 Sep 10;373(1758). pii: 20180208. doi: 10.1098/rstb.2018.0208. The same website hosts extensions of the model used in Deng, Lan; Denham, Jack E.; Arya, Charu; Yuval, Omer; Cohen, Netta; and Haspel, Gal "Inhibition Underlies Fast Undulatory Locomotion in Caenorhabditis elegans" eNeuro 23 December 2020, 8 (2) ENEURO.0241-20.2020; DOI: https://doi.org/10.1523/ENEURO.0241-20.2020. 
Type Of Material Computer model/algorithm 
Year Produced 2018 
Provided To Others? Yes  
Impact Follow up research by others in the community. Follow up collaborations (e.g. Haspel group, New Jersey Inst. Technology, USA, Tytell group, Tufts University, USA, Fauci group, Tulane University, USA and others. 
URL https://bitbucket.org/leedswormlab/curve-worm-royal-society-paper/src/master/
 
Title Open source model of C. elegans forward locomotion 
Description Model presented in Gait modulation in C. elegans: an integrated neuromechanical model Jordan H. Boyle, Stefano Berri and Netta Cohen http://www.frontiersin.org/Computational_Neuroscience/10.3389/fncom.2012.00010/abstract 
Type Of Material Computer model/algorithm 
Year Produced 2010 
Provided To Others? Yes  
Impact The publication of the source code allowed several other groups to test and extend the model. It led to a number of independent implementations. Selected examples include a novel (opensource) neuromechanical simulation framework CLONES (see https://www.youtube.com/watch?v=mM_C-AkVrDQ) as well as by Izquierdo and Beer (presenting an integrated neuromechanical model with steering; ECAL 2015, DOI /10.7551/978-0-262-33027-5-ch040; see https://www.cs.york.ac.uk/nature/ecal2015/paper-43.html). A further impact relates to outreach and public engagement - in the form of an OpenWorm Weminars (see outreach). 
URL http://journal.frontiersin.org/article/10.3389/fncom.2012.00010/full#h8
 
Title Open source model of C. elegans muscle 
Description C++ and matlab implementations of C. elegans muscle cell model presented in J.H. Boyle, N. Cohen, "Caenorhabditis elegans body wall muscles are simple actuators", BioSystems 94 (2008) 170-181. Posted (with extensions) by the OpenWorm consortium. 
Type Of Material Computer model/algorithm 
Year Produced 2011 
Provided To Others? Yes  
Impact This detailed model of C. elegans was incorportated into the OpenWorm project, as part of the community-wide effort to generate a complete model of C. elegans, with focus on the neural control of behaviour. Significant impact also includes novel extensions of neuroML (the leading neuroscience model markup language) to support the model. See http://www.opensourcebrain.org/projects/muscle_model/wiki for additional The model now runs on jNeuroML or PyNeuroML. 
URL https://github.com/openworm/muscle_model/tree/master/BoyleCohen2008
 
Description Collaboration with Erasmus MC, Rotterdam on C elegans sensory computation 
Organisation Erasmus MC
Department Department of Cell Biology
Country Netherlands 
Sector Academic/University 
PI Contribution We constructed a simulation platform in which to study how animals (C elegans worms) navigate complex chemical environments. We constructed detailed mathematical models of sensory responses to chemical cues, sensory processing, and motor control in these animals. The models include various forms of learning, to enable us to study adaptive behaviour in real-world scenarios. We used experimental data from the Jansen group to parametrise our model neurons and neural circuits. We simulated the models in virtual arenas to study the information and neural processing pathways that account for the observed behaviours. Our modelling allowed us to discover new forms of learning, new sensory capabilities, and new behaviours in these animals.
Collaborator Contribution The Jansen lab performed all the experimental work. The two labs interacted closely to iterate between experiment and theory, with experiments suggesting modeling extensions and model analysis generating predictions for experiments.
Impact PhD Thesis, Tom Sanders (2016). Paper under review: Martijn P.J. Dekkers, Tom Sanders, Oluwatoroti Umuerri, Netta Cohen and Gert Jansen, "Sensory adaptation in gustatory and nociceptive circuits regulates the balance of exploration and exploitation during salt navigation in Caenorhabditis elegans".
Start Year 2013
 
Description Collaboration with NJIT on C elegans locomotion 
Organisation New Jersey Institute of Technology
Country United States 
Sector Academic/University 
PI Contribution Our lab contributed computational modelling, theoretical predictions, experimental designs and genetic resources.
Collaborator Contribution Genetics and molecular biology; experiments.
Impact This is a highly multidisciplinary collaboration across biological sciences, engineering, biological physics, mathematics and computer science. Outputs are under preparation.
Start Year 2017
 
Description Collaboration with Nitabach group at Yale University 
Organisation Yale University
Department Yale Child Study Centre
Country United States 
Sector Academic/University 
PI Contribution Little is known about how animals integrate multiple sensory inputs in natural environments to balance avoidance of danger with approach to things of value. Furthermore, almost nothing is known about the neural circuits controlling threat-reward decision making. Given preliminary experiments by our collaborators at Yale University, we constructed a number of computational models (integrating nervous system dynamics, animal behaviour and a physical environment) that reproduced the results. We used our models to construct and parametrise experimental tests of the model predictions. Additional experiments by our collaborators confirmed one of the models. Mathematical analysis of model simulations then made further predictions about the mechanism and time scale of the decision making process, which are forming the basis for ongoing experimental work by the Yale group.
Collaborator Contribution The Yale group performed biological experiments with C.elegans worms, in which animals had to decide whether to cross a toxic barrier to reach a source of food odour. They also established that food deprivation increases the animal's propensity to cross the dangerous barrier. They then pinned down a specific neural circuit implicated in this decision and characterised cellular pathways that contribute to the neuronal functions.
Impact Ghosh DD, Sanders T, Hong S, McCurdy LY, Chase DL, Cohen N, Koelle MR.. Nitabach MN. (2016). Neural Architecture of Hunger-Dependent Multisensory Decision Making in C. elegans. Neuron, 92 (5), pp. 1049-1062
Start Year 2014
 
Description "Ingenuity and Beyond" outreach event at the University Technical College, Leeds 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Schools
Results and Impact A Postdoctoral Fellow mimicking a C. elegans navigational strategy for robotics joined members of the Self-Repairing Cities project and participated in a STEM related outreach event called Ingenuity and Beyond at the University Technical College (UTC) in Leeds. The event covered practical applications for robotics and the aimed impact of the event was to present subjects that the UTC'S own students can aspire to, as well as giving them a glimpse of work that goes on in the area at the University and other companies. The event comprised of technical activities alongside interactive talks and workshops, with the aim of adding an engaging extra dimension to the school curriculum.

Around 100 students from Y10-13 attended the talk, which included a mix of direct presentation and video footage from the project as well as a demonstration of the work on bio-inspired pot-hole searching (based on the C. elegans navigation circuit). The students were very engaged and participated by asking questions and interacting with the robot during the demonstration.
Year(s) Of Engagement Activity 2018
 
Description Interview for national news 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Professional Practitioners
Results and Impact Reportage by the British Neuroscience Association:
THE VOICE OF BRITISH NEUROSCIENCE TODAY. Issue No. 93. Autumn 2021
"Biology's hydrogen atom: Decoding the worm brain" (pp. 28-30)
Year(s) Of Engagement Activity 2022
URL https://www.bna.org.uk/publications/bna-bulletin/
 
Description Public Journal Club -- OpenWorm Weminar series, guest panelist 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Weminar title and abstract: How does a worm crawl? Seems simple, doesn't it? You'd think with all our technology in the modern age that understanding the biology behind how a microscopic worm crawls would be easy. Turns out, not so much! Come join us and explore two scientific papers from this year that explain why and what the most promising leads are. Joining us will be scientists actively working on the problem.
Year(s) Of Engagement Activity 2014
URL https://www.youtube.com/watch?v=puB8R9PW3BI
 
Description Public Journal Club -- OpenWorm Weminar series, guest panelist 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Weminar Title and abstract: OpenWorm Journal Club: Closing the Loop from Brain Cells to Behavior
"You'd think that understanding the biology behind how microscopic worms crawl would be easy, but turns out we don't fully understand it yet! Join us on Dec 11 where we will review two recent papers that propose computer models to describe how the cells of the worm create its behavior. We'll also discuss how this relates to what is going on in the OpenWorm project!"
Streamed Dec 11, 2015
Year(s) Of Engagement Activity 2015
URL https://www.youtube.com/watch?v=D3_BjL20Roc