​About​

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I'm a senior Reinforcement Learning researcher at Microsoft Research NYC.  


Research

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I study how we build models of the world and use them in memory, exploration, & planning.

I build and test neurally plausible algorithms for learning the structure of the environment. My approach combines reinforcement learning, neural networks, & machine learning with behavioral experiments, fMRI, & electrophysiology.

 

Predictive cognitive maps: My work shows that multi-scale predictive map representations updated via memory replay support abstraction & hierarchical planning.  

​Collective memory: In another line of research I've used graph theory & multi-person experiments to study how conversational networks shape collective memory (this podcast).

Computational justice: using multi-agent simulations I study systemic and structural injustice, e.g., how collective behavior incur unjust costs on minorities in institutions, and how to compare long-term policies to alleviate these costs (see Computational Justice below).

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Past

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My training is in cognitive computational neuroscience. I've previously worked at Columbia University, Electrophysiology, Memory, and Navigation Lab, did my postdoc at Princeton (where I collaborated with Ken Norman, Matt Botvinick, Jon Cohen, Nathaniel Daw), my PhD was in psychology (Berlin, Germany, Bernstein Center for Computational Neuroscience), BSc in software engineering (Tehran, Iran), & MSc in Philosophy of Science (Utrecht, Netherlands). 

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Publications & preprints

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Momennejad I (2020) Learning Structures: Predictive Representations, Replay, and Generalization. Current Opinions in Behavioral sciences.

[ Link to published article , PDF]

Brunec I, Momennejad I (2019) Predictive Representations in Hippocampal and Prefrontal Hierarchies.
[ bioRxiv preprint ]

Sievers B, Momennejad I (2019) SAMPL: Spreading Activation and Memory Plasticity Model.
[ bioRxiv preprint , Model Code on GitHub ]

Momennejad I, Sinclair S, Cikara M (2019) Computational justice: Simulating structural bias and interventions.
[ bioRxiv preprint , 04/21/2019: python workshop ]

Zorowitz S, Momennejad I, Daw N (2020) Anxiety, avoidance, and sequential evaluation. Computational Psychiatry, 0 0:0, February, 1–17.
[ Link to published paper , see 2019 bioRxiv preprint ]

Momennejad I, Duker A, Coman A (2019) Bridge ties bind collective memories. Nature Communications. 
[ open access paper ]

Momennejad I, Norman KA, Cohen JD, Singh S, Lewis RL (2019). Rational use of Episodic and Working Memory: A Normative Account of Prospective Memory. BioRxiv, 580324 https://doi.org/10.1101/580324.
[ bioRxiv preprint, SfN poster ]

Momennejad I, Howard M (2018) Predicting the future with multi-scale successor representations.
[ bioRxiv preprint, status: in revision ]

Momennejad I, Otto RA, Daw N, Norman KA (2018) Offline replay supports planning in human reinforcement learning. eLife 2018;7:e32548. 

[ eLife link, Talk at CCN 2017 , PDF,  open access dataset]

Russek E*, Momennejad I*,  Botvinick MM, Gershman SJ, Daw N (2017) Predictive representations can link model-based reinforcement learning to model-free mechanisms. Plos Comp Biol.
[ Journal link,  PDF, bioRxiv preprint,  CODE ]

Momennejad I*, Russek E*, Cheong JH, Botvinick MM, Daw N, Gershman SJ (2017) The successor representation in human reinforcement learning: evidence from retrospective revaluation. Nature Human Behaviour, 1. [ Nat Hum Beh paper , free preprint , my python tutorials comparing SR & SR-Dyna,  blogpost from Deepmind ] 

Coman A, Momennejad I, Drach R, Geana A (2016) Mnemonic convergence in social networks: The emergent properties of cognition at a collective level. PNAS. doi: 10.1073/pnas.1525569113.
[ Journal link + PDF file ]

Wisniewsky D, Reverberi C, Momennejad I, Kahnt T, Haynes J-D (2016) The role of parietal cortex in the representation of task-reward-association. The Journal of Neuroscience. [ Journal link ] 

Haynes J-D, Wisniewsky D, Gorgen K, Momennejad I, Reverberi C (2015) fMRI decoding of intentions: compositionality, hierarchy, and prospective memory. Brain-Computer Interface (BCI), 3rd International Winter Conference. doi: 10.1109/IWW-BCI.2015.7073031. [ IEEE link ]

Momennejad I, Haynes J-D (2013) Encoding of prospective tasks in the human prefrontal cortex under varying task load. The Journal of Neuroscience 33(44):17342-17349. [ Journal link + PDF file ]

Momennejad I, Haynes J-D (2012) Human anterior prefrontal cortex encodes the 'what' and 'when' of future intentions. Neuroimage 61(1):139-48.

[ Journal link + PDF file ]

Working manuscripts

 

  • Russek E, Momennejad I,  Botvinick MM, Gershman SJ, Daw N (in prep) Predictive representations in human prefrontal cortex and the hippocampus. 
     

  • Momennejad I*, Tomov M*, Norman KA, Cohen JD (in prep) The strategic allocation of working memory and episodic memory in cognitive control: A neural network model of prospective memory. [ poster PDF file ]
     

  • Momennejad I, Cohen JD, Norman KA (in prep) MVPA evidence of episodic future simulation predicts goal-directed behavior in prospective memory. [ Ask me about it! ]
     

  • Momennejad I, Reverberi C, Haynes J-D (in prep) Sequence effects: Task similarity facilitation and dissimilarity costs in the planning and execution of task sequences. [ poster PDF file ]

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Recent Teaching

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Recent Talks and Workshops (since April 2019)

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April 21, 1-5 PM: Computational Justice Workshop (hands-on agent-based simulation in Python), Heart of the Machine series, Pioneerworks, Brooklyn, NY

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May 13-14: Context and Episodic Memory (CEMS), Philadelphia, PA

 

May 16-18: Control Processes 2019, Brown University, Providence, RI

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May 28-29: Talk and visit, Computational Neuroscience Center, University of Washington, Seatle, WA

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July 10, 1-5PM: Structure for Efficient Reinforcement Learning (SERL) Workshop
4th Multidisciplinary Conference on Reinforcement Learning and Decision Making (RLDM), Montreal, Canada

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August 8-17: "Cognitive Maps" at MIND19 summer school for computational methods in neuroscience at Dartmouth​

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September 10-13: What is biological Computation? Santa Fe Institute

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Book chapters 

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  • Momennejad I, Allahyari M (2017) Refiguring: in Conversation. Futureproof, Haverford College, Haverford, PA, pp 16-31.

  • Momennejad I (2011) Thinking in movements, rehearsing freedom. In: Wagner L and Gomes-Carrillo de Castro Eds., Sounds, Space, Body, a process. Ernst Schering Foundation and Association of Neuroesthetics: Berlin, pp:115-125.

  • Momennejad I (2011) Seeing with eyes closed: the neuro-epistemology of perceptual reality. In: Agudio E and Franke I Eds., Seeing with eyes closed. Association of Neuroesthetics: Berlin, pp:15-21.

  • Momennejad I and Franke I (2011) Two practices of seeing with eyes closed: contemporary art and science in dialogue. In: Agudio E and Franke I Eds., Seeing with eyes closed. Association of Neuroesthetics: Berlin, pp:9-13.

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Media: Talks, outreach, press

 

ida.m [at] columbia.edu
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