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Chris Mathys, friend of clarity about scarcity Profile
Chris Mathys, friend of clarity about scarcity

@chmathys

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424

Loves 🐂; has impressive credentials; and doesn't want the cure when it's worse than the disease

Aarhus, Denmark
Joined April 2014
Don't wanna be here? Send us removal request.
@alex_j_hess
Alex Hess
9 months
Are you new to the field of Computational Psychiatry or just looking for resources on applying Bayesian models of cognition to behavioural data? Then check out our new paper "Bayesian Workflow for Generative Modeling in Computational Psychiatry": https://t.co/GQUIIcUdhr 1/6
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@DrBreaky
Michael Breakspear
10 months
Early bird registrations for the 2025 Brain Connectivity Meeting now open June 20 (arrive) until June 22 on the beautiful North Stradbroke Island (Minjerribah), near Brisbane (location of OHBM) https://t.co/GJbiNkK5oQ
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@IntiBrazil
Inti
10 months
#SAMBAlab Paper alert, written by @D_Atanassova et al. Exploring when to exploit: The cognitive underpinnings of foraging-type decisions in relation to psychopathy. w/@cognemo_andreea,@chmathys & others. @SSSpsychopathy @SSSPStudents @decisioncenter👇🏾👀 https://t.co/n7W6zkwxKB
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nature.com
Translational Psychiatry - Exploring when to exploit: the cognitive underpinnings of foraging-type decisions in relation to psychopathy
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@interact_minds
Interacting Minds
1 year
We are indescribably sad to announce the passing of our dear friend and colleague Kristian Tylén His presence at the IMC will be forever missed and his impact on us all is beyond words Our thoughts are with his wife and children in this difficult time https://t.co/v810Wxqjkz
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arts.au.dk
Aarhus University has lost an ingenious scientist and a generous friend and mentor for his colleagues and students.
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@ESterner_
Elisabeth Sterner
1 year
Super excited to share our new preprint, led by my supervisor Franziska Knolle in collaboration with Verena Demler, @Lucy_MacG & @chmathys: 💡Guided by Expectations: Overweighted Semantic Priors in Schizotypy and their Links to Glutamate https://t.co/ffxyc4B9DP A thread 🧵:
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@RockBerta
Roberta Rocca (@rockberta.bsky.social)
1 year
Folks in 🇩🇰 & beyond! On Oct 1st, we are hosting (@interact_minds) a workshop exploring research at the intersection of NLP x social sciences, cognition, & humanities, with 3 awesome keynotes by @dirk_hovy, @maria_antoniak & @sandropezzelle. Register here:
interactingminds.au.dk
Workshop at IMC
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@chmathys
Chris Mathys, friend of clarity about scarcity
1 year
Great to see this out - congratulations @D_Atanassova !
@CommsPsychol
Communications Psychology
1 year
Higher levels of psychopathic traits were associated with reduced pain sensitivity and a greater tendency to ignore new evidence and maintain prior expectations in pain learning situations. https://t.co/FxB9zwNjpF @D_Atanassova @Inti_Brazil @cognemo_andreea @chmathys @DondersInst
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@D_Atanassova
Dimana Atanassova
1 year
🧵Why do people with psychopathic traits stick to maladaptive patterns of behaviour? The answer: a cognitive rigidity mechanism prompts them to ignore new evidence and maintain prior expectations in pain learning situations. 1/3 https://t.co/GhzrBMeFDq
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nature.com
Communications Psychology - Higher levels of psychopathic traits were associated with reduced pain sensitivity as well as a greater tendency to ignore new evidence and maintain prior expectations...
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@chmathys
Chris Mathys, friend of clarity about scarcity
1 year
@PTWaade This has been a long haul – the main work was done as part of @lilwebian's PhD at the #TNU @ETH_en, with Klaas and me. Years later, Nicolas, @PTWaade and Anna came onboard and made shiny toolboxes from our initial codebase. First preprint May 2023. Glad to finally share it! 10/
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@chmathys
Chris Mathys, friend of clarity about scarcity
1 year
@PTWaade We also provide some examples for the kinds of models you can now build within the HGF framework – from global volatility beliefs, multimodal inference, multisensory cue combination over time, etc etc – check it out! https://t.co/oxzCHeoW3o 9/
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@chmathys
Chris Mathys, friend of clarity about scarcity
1 year
@PTWaade There’s plenty more in the preprint. For example, we find that the message passing implied by value coupling in the HGF is mostly equivalent to what has been proposed for PC, with small, but interesting differences. 8/
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@chmathys
Chris Mathys, friend of clarity about scarcity
1 year
Even better, we implemented the gHGF in two(!) openly available toolboxes for you: 1. In Python (led by Nicolas Legrand): https://t.co/Sb98wJPYnE 2. In Julia (led by @PTWaade): https://t.co/wn4WzH7CEM 7/
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github.com
The Julia implementation of the generalised hierarchical Gaussian filter - ComputationalPsychiatry/HierarchicalGaussianFiltering.jl
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@chmathys
Chris Mathys, friend of clarity about scarcity
1 year
This modular architecture of the generalised HGF means that it’s now super simple to build your own models under the HGF – you can literally add or remove nodes in your belief network and don’t need to worry about deriving any new equations! 6/
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@chmathys
Chris Mathys, friend of clarity about scarcity
1 year
Here, we generalise the HGF to encompass both value and volatility coupling, all under the same framework, with one-step belief updates driven by precision-weighted prediction errors, and a modular belief network architecture. 5/
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@chmathys
Chris Mathys, friend of clarity about scarcity
1 year
In contrast, PC typically focuses on hierarchies in which higher level beliefs concern the *value* of lower levels. This is useful for understanding how beliefs about lower-level features depend on context (higher-level beliefs) (e.g., Rao & Ballard, 1999). 4/
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@chmathys
Chris Mathys, friend of clarity about scarcity
1 year
In current HGF models, higher level beliefs encode the *volatility* of lower levels. This is motivated by the observation that learning should be influenced by environmental uncertainty: if the world is currently changing faster (volatile), the agent needs to learn faster. 3/
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@chmathys
Chris Mathys, friend of clarity about scarcity
1 year
Predictive coding and the HGF are algorithms where messages are passed between the nodes of hierarchical Bayesian models, but they tend to assume different kinds of belief hierarchies: volatility coupling (HGF) versus value coupling (PC). What does that mean?? 2/
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@chmathys
Chris Mathys, friend of clarity about scarcity
1 year
Here's a copy of @lilwebian's thread on the generalized HGF https://t.co/oxzCHeoW3o 👇 1/
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arxiv.org
Hierarchical Bayesian models of perception and learning feature prominently in contemporary cognitive neuroscience where, for example, they inform computational concepts of mental disorders. This...
@lilwebian
Lilian Aline Weber
1 year
This is work with @chmathys, @PTWaade, Nicolas, Anna and Klaas. For the actual thread, come to where the skies are blue!
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@lilwebian
Lilian Aline Weber
1 year
If you want to have a chat about this, meet me today at #IWAI2024 or the rest of the week at the #CPC in Zurich. There, we will also present the new toolboxes implementing all of this: https://t.co/EBXVW9iIXx (led by Nicolas) and https://t.co/wLA4jPSMxI (led by @PTWaade)
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github.com
The Julia implementation of the generalised hierarchical Gaussian filter - ComputationalPsychiatry/HierarchicalGaussianFiltering.jl
@lilwebian
Lilian Aline Weber
1 year
Long overdue #tweeprint: ✨The generalised hierarchical Gaussian filter✨ Ever wanted to build your own hierarchical Bayesian learning model without deriving/implementing new equations? Ever wondered how the HGF relates to predictive coding? See here👇 https://t.co/JvUzdSm8Sz
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