Ritwik K. Niyogi

I am a Sir Henry Wellcome Post-doctoral Fellow, now hosted by University College London. I am at the UCL-Max Planck Centre for Computational Psychiatry and Ageing Research. My Research Sponsor is Dr.Robb Rutledge. My mentor is Professor Nathaniel Daw at the Princeton Neuroscience Institute.

I did my PhD in Machine Learning and Theoretical Neuroscience at the Gatsby Computational Neuroscience Unit, University College London (UCL), supervised by Professor Peter Dayan. I did a minor in Reinforcement Learning with Dr. David Silver.

I was formerly hosted by the University of Oxford, based at the Department of Experimental Psychology, my Research Sponsor was Dr. Mark Walton and Sponsor was Professor Matthew Rushworth.

I previously did the first two parts of my Sir Henry Wellcome fellowship investigating vigour-anergia, reward learning and real-time cost-benefit decision-making at the (1) Solomon H. Snyder Department of Neuroscience and Brain Science Institute, the Johns Hopkins University School of Medicine, (my Research Sponsor was Dr.Jeremiah Cohen ) and (2) Department of Psychiatry, UNC Neuroscience Center, University of North Carolina at Chapel Hill with Research Sponsor Prof. Garret Stuber).

About Me

Coming soon, Stay Tuned.

Contact

University College London

UCL-Max Planck Centre for Computational Psychiatry and Ageing Research

Russell Square House

10-12 Russell Square

London, WC1B 5EH

United Kingdom

E-mail: ritwik7@gmail.com / ritwik.niyogi@gatsby.ucl.ac.uk

Curriculum Vitae

News

2019

  • Our work Vigour as a diagnostic of apathy: sensitivity to opportunity costs of time predicts action latencies: has been accepted at Reinforcement Learning and Decision Making (RLDM), 2019.

2018

  • I have started the final phase of my Sir Henry Wellcome fellowship at the UCL-Max Planck Centre for Computational Psychiatry and Ageing Research. My Research Sponsor is Dr. Robb Rutledge. I aim to apply machine learning and AI to longitudinally track inviduals (healthy and clinical populations) playing games on smartphone apps, assess their vigour-anergia, and identify when at-risk individuals in the healthy population may become likely to develop clinical depression. The mission: better diagnostics for clinical depression.

2017

  • I have started the next phase of my Sir Henry Wellcome fellowship at the Department of Psychiatry, UNC Neuroscience Center, University of North Carolina at Chapel Hill.

  • I have developed a novel assay of vigour-anergia in head-fixed animals. I plan to develop this as a model of anergia that can be targeted with novel drugs and therapeutics. The mission: turbo charging target discovery for clinical depression and Parkinson's.

2016

  • I have combined electrophysiology, optogenetics, behaviour and theory to record my first optogenetically photo identified dopamine neurons during awake behavioural tasks. They do not signal what you would predict! What does Mean Dopamine even mean?

2015

2014

  • New paper published: Niyogi, R.K., Shizgal, P., & Dayan, P. Some work and some play: microscopic and macroscopic approaches to labor and leisure PLoS Computational Biology 10(12): e1003894 (2014) Pubmed

  • I have successfully defended my PhD thesis in June: What to do, when to do it, how long to do it for: a normative microscopic approach to the labour leisure tradeoff . Committee: Dr. David Silver and Professor Matthew Botvinick.

2013

  • I am organising the Uncertainty Club. Speakers so far: Tim Behrens (Sep 2013), Peter Dayan (Nov 2013), Bahador Bahrami (Nov 2013).

Research Interests

In Preparation

Publications

  • Ahilan, S., Solomon, R., Breton Y-A, Conover, K., Niyogi, R.K., Shizgal P., Dayan, P. Forgetful inference in a sophisticated world model , PLoS Computational Biology (accepted) pdf BioArxiv

  • Niyogi, R.K., Shizgal, P., & Dayan, P. Some work and some play: microscopic and macroscopic approaches to labor and leisure , PLoS Computational Biology 10(12): e1003894 (2014) pdf Pubmed

  • Niyogi, R.K., Breton, Y-A, Solomon, R.B., Conover, K., Shizgal, P., & Dayan, P. Optimal indolence: a normative microscopic approach to work and leisure, Journal of the Royal Society Interface,11, 20130969 (2014) pdf Supplementary Information Pubmed

  • Niyogi, R.K. & Wong-Lin, K-F, Dynamic excitatory and inhibitory gain modulation can produce flexible, robust and optimal decision-making, PLoS Computational Biology, 9(6):e1003099 (2013) pdf Pubmed

  • Balci, F., Simen, P., Niyogi, R., Saxe, A., Hughes, J.A., Holmes, P., & Cohen, J.D. Acquisition of decision making criteria: accuracy ultimately loses the competition with reward rate, Attention Perception Psychophysics, 73(2), 640-657 (2011) pdf Supplementary Material Pubmed

  • Niyogi, R.K. & English, L.Q. Learning-rate-dependent clustering and self-development in a network of coupled phase oscillators, Physics Review E, 80, 066213 (2009) pdf Pubmed

Conference Proceedings

  • Nair, A *., Niyogi, R.K.*, Tabrizi, S., Rees, G., & Rutledge, R.B. Vigour as a diagnostic of apathy: sensitivity to opportunity costs of time predicts action latencies. Reinforcement Learning and Decision Making (RLDM), 2019, Montreal, QC.

  • Bari, B.A., Grossman, C., Niyogi, R.K., Cohen, J.Y. Action-outcome encoding in dorsomedial prefrontal cortex. Society for Neuroscience, Washington DC, 2017.

  • Ahilan, S., Solomon, R., Conover, K., Niyogi, R.K., Shizgal P., Dayan, P. Observing the observer observing: forgetful world modelling in a self-stimulation task. Reinforcement Learning and Decision Making (RLDM), 2017, Ann Arbor, MI; Computational and Systems Neuroscience (Cosyne), 2017, Salt Lake City, UT.

  • Guez, A., Niyogi, R., Bach, D., Dolan, R. & Dayan, P. A normative theory of approach-avoidance conflicts during dynamic foraging in humans. Reinforcement Learning and Decision Making (RLDM), 2013, Princeton, NJ.

  • Niyogi, R.K., Breton, Y.A, Solomon, R.B., Conover, K., Shizgal, P., & Dayan, P. Some work and some play: a normative, microscopic approach to allocating time between work & leisure. Computational and Systems Neuroscience (Cosyne), 2013, Salt Lake City, UT.

Also presented at Symposium on the Biology of Decision Making (SBDM) Paris, 2013.

  • Niyogi, R.K., Breton, Y.A., Conover, K., Solomon, R.B., Shizgal, P., & Dayan, P. Semi-Markov models of the molecular psychophysics of brain stimulation reward. Computational and Systems Neuroscience (Cosyne), 2012, Salt Lake City, UT.

Also presented at Federation of European Neurosciences (FENS), 2012, Barcelona, Spain.

  • Niyogi, R.K., & Wong-Lin, K-F. Time-varying gain modulation on neural circuit dynamics and performance in perceptual decisions. Computational and Systems Neuroscience (Cosyne), 2010, Salt Lake City, UT.

  • Niyogi, R., & Wong-Lin, K-F. Dynamical Effects of Non-Linearities and Time-Varying Gain Modulation in Neurally Plausible Network Models of Perceptual Decision-Making. Sigma Xi Student Research Symposium, 2009, Saint Joseph’s University, Philadelphia, PA.

  • Niyogi, R., & English, L.Q. Synchronization and Hebbian Learning in a Network of Coupled Neural Phase Oscillators. Sigma Xi Student Research Symposium, 2009, Saint Joseph’s University, Philadelphia, PA.

  • Niyogi, R., Gleichgerrcht, E., & Abrams, R.L. How Smart is the Unconscious? Exploring the Limits of Unconscious Cognition through the Two-Word Challenge. 4th Annual Undergraduate Science Research Symposium, 2007, Ursinus College, Collegeville, PA.

  • Abrams, R.L., Stull, S., Rockman, L., Niyogi, R., & Fisher, F. Unconscious processing of visually masked words by second-and third-grade children. Eastern Psychological Association (EPA) Conference, 2007, Philadelphia, PA.

  • Abrams, R.L., Ilieva, I., Niblock, A., Niyogi, R., & Shainheit, C. Unconscious Semantic Priming in the Absence of Partial Awareness. Eastern Psychological Association (EPA) Conference, 2006, Baltimore, MD. (This research was subsequently reported in the paper: Abrams, R.L., & Grinspan, J. (2007). Unconscious priming in the absence of partial awareness, Consciousness and Cognition, 16(4), 942-953; my contribution is acknowledged in an Authors’ Note)

Theses

  • What to do, when to do it, how long to do it for: a normative microscopic approach to the labour leisure tradeoff (PhD Thesis, University College London)

  • The Source of Suboptimality in Human Performance on Two-Alternative Forced Choice Motion-Discrimination Decision-Making Tasks (Neuroscience Honors Thesis, Dickinson College)

  • Dynamical Effects of Non-Linearities and Time-Varying Gain Modulation in Neurally Plausible Network Models of Perceptual Decision-Making Tasks (Mathematics Honors Thesis, Dickinson College)

  • Synchronization and Hebbian Learning in a Network of Coupled Neural Phase Oscillators (Physics Honors Thesis, Dickinson College)

Collaborators

I have had the privilege of working with and being mentored by

I follow (and often preach) the work of my friends:

Teaching

Links

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