alimahmoodi.bsky.social
Ali Mahmoodi
@alimahmoodi.bsky.social
57 followers 41 following 12 posts
Neuroscientist in Oxford, interested in learning and decision making. Former engineer, reader, patzer.
Posts Media Videos Starter Packs
alimahmoodi.bsky.social
Ali Mahmoodi @alimahmoodi.bsky.social · Sep 4
Brain-wide representations of prior information in mouse decision-making
www.nature.com/articles/s41...
Brain-wide representations of prior information in mouse decision-making - Nature
Brain-wide recordings in mice reveal that prior expectations are distributed through recurrent loops across all levels of cortical and subcortical processing.
www.nature.com
2
Reposted by Ali Mahmoodi
stepalminteri.bsky.social
Stefano Palminteri @stepalminteri.bsky.social · Sep 3
New paper our in @pnas.org, lead by @isabellehoxha.bsky.social with Léo Sperber. We use evolutionary simulation to assess and compare the adaptive value of positivity bias and gradual perseveration in reinforcement learning. Follow the thread below (and Isabelle!) for more details!
isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Sep 3
Ever wondered why you keep going to that restaurant with stale fries? Is it because you went often in the past (perseveration) or because you remember past good experiences better (positivity bias)? Our study out in PNAS investigates the normative basis for these biases www.pnas.org/doi/10.1073/...
Evolving choice hysteresis in reinforcement learning: Comparing the adaptive value of positivity bias and gradual perseveration | PNAS
The tendency to repeat past choices more often than expected from the history of outcomes has been repeatedly empirically observed in reinforcement...
www.pnas.org
7 37
alimahmoodi.bsky.social
Ali Mahmoodi @alimahmoodi.bsky.social · Aug 28
I’m glad to have played a small part in this project, where the brilliant Deng Pan combined modelling, fMRI and ultrasound stimulation to demonstrate the causal role of the hippocampus in learning based on inference. See Deng's thread below
dengpan.bsky.social
Deng Pan @dengpan.bsky.social · Aug 28
🚨We believe this is a major step forward in how we study hippocampus function in healthy humans.

Using novel behavioral tasks, fMRI, RL & RNN modeling, and transcranial ultrasound stimulation (TUS), we demonstrate the causal role of hippocampus in relational structure learning.
5
Reposted by Ali Mahmoodi
mkflugge.bsky.social
Miriam Klein-Flügge 🧠 @mkflugge.bsky.social · Aug 20
We are super excited about the first human transcranial ultrasound study from our lab which is now on BiorXiv, showing the amygdala‘s role in processing ambiguous emotions and showing TUS changed resting-state connectivity and metabolite concentrations (GABA) in the amygdala - a huge team effort! 🥳🙏🏼
johalgermissen.bsky.social
Johannes Algermissen @johalgermissen.bsky.social · Aug 20
Very happy to share my first preprint from @oxexppsy.bsky.social @oxneuro.bsky.social ! We (me + co-first authors @lilweb.bsky.social @mirunarascu.bsky.social + PI @mkflugge.bsky.social + many others) used transcranial focused ultrasound stimulation (TUS/tFUS/LIFU) of the human amygdala ... (1/15)
1 8 34
Reposted by Ali Mahmoodi
payampiray.bsky.social
Payam Piray @payampiray.bsky.social · Aug 12
New paper with @nathanieldaw.bsky.social in Nature Communications: an RL model that builds a successor map compositionally. The new model plans as well as the best models, and it links components of the map used for planning to neural codes in the medial entorhinal cortex.
rdcu.be/eAofi
Reconciling flexibility and efficiency: medial entorhinal cortex represents a compositional cognitive map
Nature Communications - How the brain creates compositional cognitive maps that support both flexible and efficient planning remains poorly understood. Here, authors propose a...
rdcu.be
1 20 76
Reposted by Ali Mahmoodi
mkwittmann.bsky.social
Marco K Wittmann @mkwittmann.bsky.social · Aug 7
📢 Job announcement: Two (!) 3-year postdoc jobs in our lab at UCL 📢

🧠💫🔊 We are looking for postdocs interested in the abstract mechanisms underlying social cognition. Modelling, fMRI and non-invasive ultrasound, a new deep-brain stimulation method.

Please RT

www.ucl.ac.uk/work-at-ucl/...
UCL – University College London
UCL is consistently ranked as one of the top ten universities in the world (QS World University Rankings 2010-2022) and is No.2 in the UK for research power (Research Excellence Framework 2021).
www.ucl.ac.uk
3 55 61
alimahmoodi.bsky.social
Ali Mahmoodi @alimahmoodi.bsky.social · Aug 5
Individual differences in decision-making shape how mesolimbic dopamine regulates choice confidence and change-of-mind www.nature.com/articles/s41...
Individual differences in decision-making shape how mesolimbic dopamine regulates choice confidence and change-of-mind - Nature Neuroscience
Differences in neuroeconomic decision-making influence nucleus accumbens dopamine dynamics and reflect choice confidence during evaluation, as well as past and future value during re-evaluation, which...
www.nature.com
2
alimahmoodi.bsky.social
Ali Mahmoodi @alimahmoodi.bsky.social · Jul 29
This is cool!
bjornlindstrom.bsky.social
Björn Lindström @bjornlindstrom.bsky.social · Jul 23
Thrilled that our paper on the mechanisms underlying social learning strategies is out! First big paper from my @erc.europa.eu & @kawresearch.bsky.social funded group. More to come! I'm currently looking to recruit two post docs, get in touch if you find this line of research interesting.
nathumbehav.nature.com
Nature Human Behaviour @nathumbehav.nature.com · Jul 23
Through experiments and simulations, this study shows how individuals learn to learn from others, dynamically shaping the processes involved in cultural evolution. @davidschultner.bsky.social @bjornlindstrom.bsky.social
@lucasmolleman.bsky.social
www.nature.com/articles/s41...
1
Reposted by Ali Mahmoodi
seongminpark.bsky.social
Seongmin Park @seongminpark.bsky.social · Jul 10
🚨 We’re hiring! The Computational Cognitive Neuroscience Lab at Virginia Tech is looking for a postdoc to join our team studying the neural + computational mechanisms of structure learning and flexible cognition: ccnvt.github.io#positions
CCN Lab
ccnvt.github.io
1 19 29
alimahmoodi.bsky.social
Ali Mahmoodi @alimahmoodi.bsky.social · Jul 9
We have a Research Assistant position available in Rushworth Lab to help us with projects involving fMRI, TMS, and TUS. Find out more here my.corehr.com/pls/uoxrecru...
Job Details
my.corehr.com
4 4
Reposted by Ali Mahmoodi
ninarouhani.bsky.social
Nina Rouhani @ninarouhani.bsky.social · May 29
new paper from a collaborative endeavor! (@co0p3r.bsky.social) we find & replicate food-reward biases in a reinforcement learning task (where food stim are incidental)

people with eating disorder symptoms show a low-calorie food bias while those without show a high-calorie food bias... (1/3)
Eating disorder symptoms and emotional arousal modulate food biases during reward learning in females - Nature Communications
Disordered eating can disrupt the rewarding value of food. Here, the authors show in a female sample that eating disorder symptoms, emotional arousal, and interoceptive awareness modulate goal-ir...
www.nature.com
1 9 16
Reposted by Ali Mahmoodi
melgaby.bsky.social
Mohamady El-Gaby @melgaby.bsky.social · May 28
Completing the mouse, ANN, human trilogy of projects, here are two openings to study cognitive map deficits in human psychosis patients with the inimitable @mattnour.bsky.social
Using functional neuroimaging and planning tasks.
If you’re keen to join us then apply!
mattnour.bsky.social
Dr Matthew Nour @mattnour.bsky.social · May 28
🚨 Job adverts LIVE! 🚨

We want to understand how the brain supports abstract cognition in psychosis, using cutting-edge neuroscience.

Non-Clinical RA:
lnkd.in/eva-Zzfj

Clinical RA:
lnkd.in/eSgdad_F

Postdoc:
lnkd.in/eid8gtbR

Oxford University
Due June 23
3 4
Reposted by Ali Mahmoodi
stepalminteri.bsky.social
Stefano Palminteri @stepalminteri.bsky.social · May 26
New in Nature MentalHealth! with Vrizzi, Najar, Lemogne, and @mael-lebreton.bsky.social

We tested whether behavioural and RL-based model parameters are test-retest reliable and predict mental health traits.

The result? Not really.

A cautionary tale for comp. psychiatry
doi.org/10.1038/s442...
Behavioral, computational and self-reported measures of reward and punishment sensitivity as predictors of mental health characteristics - Nature Mental Health
Reinforcement learning task-based behavioral and computational measures displayed low test–retest reliability at the individual level. Also in contrast to self-assessed personality measures, behaviora...
doi.org
2 28 54
Reposted by Ali Mahmoodi
harootonian.bsky.social
Sev Harootonian @harootonian.bsky.social · May 19
🚨 New preprint alert! 🚨

Thrilled to share new research on teaching!
Work supervised by
@cocoscilab.bsky.social, @yaelniv.bsky.social, and @markkho.bsky.social.

This project asks:
When do people teach by mentalizing vs with heuristics? 1/3

osf.io/preprints/os...
2 14 33
alimahmoodi.bsky.social
Ali Mahmoodi @alimahmoodi.bsky.social · Apr 30
Humans learn generalizable representations through efficient coding
www.nature.com/articles/s41...
Humans learn generalizable representations through efficient coding - Nature Communications
Reinforcement learning models of human behavior are limited in explaining the capacity for generalization. Here, the authors propose an efficient coding principle for reinforcement learning, whereby a...
www.nature.com
1 1
alimahmoodi.bsky.social
Ali Mahmoodi @alimahmoodi.bsky.social · Apr 15
Hippocampal output suppresses orbitofrontal cortex schema cell formation
www.nature.com/articles/s41...
Hippocampal output suppresses orbitofrontal cortex schema cell formation - Nature Neuroscience
Inactivation of the ventral subiculum does not change existing schema cells in the orbitofrontal cortex (OFC) but aids their formation during new learning. This challenges the idea that the OFC relies...
www.nature.com
1
Reposted by Ali Mahmoodi
stepalminteri.bsky.social
Stefano Palminteri @stepalminteri.bsky.social · Apr 14
🚨 New study alert! 🚨
Ever wondered if rats and humans learn in the same way? 🐭🧑‍🔬
We tested this — and the answer is yes, at least when it comes to how we value rewards in context.
(with @shaunaparkes.bsky.social Lachlan Ferguson, Magdalena Soukupova)

🧵Thread 👇

1/

www.biorxiv.org/content/10.1...
Reference Point-Dependent Reinforcement Learning in Humans and Rats
Previous studies indicate that rewards and punishments in reinforcement learning are encoded in a relative manner. Reference point-dependence, a valuation bias shared by eminent adaptation level and p...
www.biorxiv.org
1 18 35
Reposted by Ali Mahmoodi
bstaresina.bsky.social
Bernhard Staresina @bstaresina.bsky.social · Apr 7
join us at @oxexppsy.bsky.social | @ox.ac.uk!
katschruers.bsky.social
Katrijn Schruers @katschruers.bsky.social · Apr 7
We're excited to share that our lab is hiring for the position of Lab Manager/Research Assistant. A great opportunity to join our lab!

You can find full details and apply via the link below:
www.jobs.ac.uk/job/DMN515/r...

Please feel free to share this with anyone who might be interested!
Research Assistant/Lab Manager at University of Oxford
Looking for a new job opportunity in academia? Check out this job opening for a Research Assistant/Lab Manager on jobs.ac.uk!
www.jobs.ac.uk
18 11
alimahmoodi.bsky.social
Ali Mahmoodi @alimahmoodi.bsky.social · Apr 2
Blimey! Machine-unique chess knowledge from an AI system (AlphaZero) can be transferred to four current or former world chess champions.
www.pnas.org/doi/10.1073/...
Bridging the human–AI knowledge gap through concept discovery and transfer in AlphaZero | PNAS
AI systems have attained superhuman performance across various domains. If the hidden knowledge encoded in these highly capable systems can be leve...
www.pnas.org
1
alimahmoodi.bsky.social
Ali Mahmoodi @alimahmoodi.bsky.social · Apr 2
So nice!
1 1
Reposted by Ali Mahmoodi
tadegquillien.bsky.social
tadegquillien.bsky.social @tadegquillien.bsky.social · Mar 31
Our new paper with Max Taylor-Davies introduces a resource-rational model of Theory of Mind.

The model can explain many of the successes and failures of mindreading in human adults and children, and non-human primates. 🧵
2 20 62
Reposted by Ali Mahmoodi
summerfieldlab.bsky.social
Chris Summerfield @summerfieldlab.bsky.social · Mar 24
getting this paper published was a bit painful but I am proud of it: www.nature.com/articles/s41.... We use deep RL to find mechanisms that help (real) people sustain the commons. Well done to Raphael Koster and Miruna Pislar (not on BlueSky). non-paywalled version on arxiv.
Deep reinforcement learning can promote sustainable human behaviour in a common-pool resource problem - Nature Communications
Koster et al introduce a deep reinforcement learning (RL) mechanism designed to manage common-pool resources successfully encourages sustainable cooperation among human participants by dynamically adj...
www.nature.com
1 23 58
Reposted by Ali Mahmoodi
neuroprinciplist.bsky.social
Shervin Safavi @neuroprinciplist.bsky.social · Feb 20
Re-posting is appreciated: We have a fully funded PhD position in CMC lab @cmc-lab.bsky.social (at @tudresden_de). You can use forms.gle/qiAv5NZ871kv... to send your application and find more information. Deadline is April 30. Find more about CMC lab: cmclab.org and email me if you have questions.
forms.gle
3 89 77
Reposted by Ali Mahmoodi
arkadykonovalov.bsky.social
Arkady Konovalov @arkadykonovalov.bsky.social · Mar 17
🚨 New paper 🚨

Out in @commspsychol.bsky.social: "Manipulating attention facilitates cooperation" with Claire Lugrin and @ccruff.bsky.social

We use gaze data and display manipulations in one-shot Prisoner's Dilemma games and find that these manipulations can drive choices through attention 👇
commspsychol.nature.com
Communications Psychology @commspsychol.nature.com · Mar 17
In a one-shot prisoner’s dilemma game, manipulating the location of payout information on computer screens changed participants’ gaze pattern sequences and resulted in greater cooperation when more focus was given to others’ outcomes.
www.nature.com/articles/s44...
Manipulating attention facilitates cooperation - Communications Psychology
In a one-shot prisoner’s dilemma game, manipulating the location of payout information on computer screens changed participants’ gaze pattern sequences and resulted in greater cooperation when more fo...
www.nature.com
10 19
Reposted by Ali Mahmoodi
mkwittmann.bsky.social
Marco K Wittmann @mkwittmann.bsky.social · Mar 13
New paper from our lab now in @nature.com . We show that our brains use basis functions or "building blocks" to navigate social interactions. Rather than tracking every individual separately, social information is compressed into patterns that can be flexibly combined. www.nature.com/articles/s41...
Basis functions for complex social decisions in dorsomedial frontal cortex - Nature
A study combining group decision-making tasks with fMRI shows that the brain’s dorsomedial prefrontal cortex uses basis functions, similar to those in the visual, motor and spatial domains, to re...
www.nature.com
8 35 130