Simon Ciranka

📣 Applications for the 23rd Summer Institute on Bounded Rationality are now open!

✨Join us in Berlin @arc-mpib.bsky.social June 08–16, 2026, to explore the topic of “Decision Making in the Age of AI”.

✏️ More details + application form (deadline: March 16): www.mpib-berlin.mpg.de/research/res...

Big news: I started a new position as Professor for Computational Social Science (W1 tenure track) at the Center for Critical Computational Studies (C3S) at Goethe University in Frankfurt am Main!

www.c3s-frankfurt.de/who-we-are#m...

Very happy to see our ice-fishing paper on the cover of @science.org this week! 🎣🎉

We tracked large groups of Finnish competitive ice-fishers to study how social foragers use social information when searching for resources. 🐟

Link: www.science.org/doi/10.1126/... (contact me for open access)

🎉 My PhD work has just been published in @natcomms.nature.com!

How do we learn who caused what - and how much control we had - when outcomes depend on multiple people? We studied how humans do so using a new social learning task, computational modelling and fMRI.

www.nature.com/articles/s41...
🧵👇

Low socioeconomic status amplifies the perceived rarity of large rewards Decision-making relies on heuristics derived from past experiences that likely vary with socioeconomic status. We investigate socioeconomic difference…

NEW: We show and replicate socioeconomic gradients in heuristics for decision-making under uncertainty, possibly reflecting adaptations varying levels of scarcity and competition for resources 🫰
Shoutout and thanks to @danielnettle.bsky.social & @coraliechevallier.bsky.social ❤️‍🔥

tinyurl.com/mu7rzz6k

Low socioeconomic status amplifies the perceived rarity of large rewards Decision-making relies on heuristics derived from past experiences that likely vary with socioeconomic status. We investigate socioeconomic difference…

Do people judge what is going to happen in unknown situations differently depending on their socioeconomic position? Yes, if you experience lower socioeconomic position, you think the big rewards are even more unlikely to come your way: www.sciencedirect.com/science/arti...

Bridging Fields in Psychology and Neuroscience with Multidisciplinary Collaboration Strengthening collaboration to encourage novel research connections between scientific areas is central to the CIMCYC - María de Maeztu Unit of Excellence strategy . To encourage this, the CIMCYC has ...

It’s official! The postdoc positions announcement is here 🚀
If you know great candidates interested in attention, memory transformation and EEG, please help spread the word:
Project (ReDAS) -> cimcyc.ugr.es/en/informati...
Job offer -> cimcyc.ugr.es/en/informati...

Waiting time during admission procedures increases social inequalities in higher education | PNAS Many domains in life require people to wait to access better outcomes, such as waiting in line to access prized tickets for a show, waiting to obta...

Happy to share our latest study published in PNAS.

Using data from 274,316 French students, we find that lower-SES students are less likely to wait for better university offers, even when waiting would lead to more prestigious or better-fit programs.
www.pnas.org/doi/10.1073/...

Simulating theories about how solving this task could develop (see teaser picture), we show that the most likely candidate here is the developmental increasing tendency to parse complex information into simplifying abstract social basis functions, like the brain does in other domains all the time 😍

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...

With a group experiment, Marco recently established that ppl use abstract combinatorial representations of social group structures to solve social decision-making tasks. www.nature.com/articles/s41...
Using these "social basis functions" involves the dmPFC, which still develops during adolescence 🧠

🥳!!NEW PREPRINT!!🥳

We show that the tendency to compress complex social information into priors about social structures becomes more pronounced during adolescence.

osf.io/preprints/ps...

I am soooooo excited to share this work, together with @mkwittmann.bsky.social and @yongling.bsky.social.

Just 1 week to apply! 4 year @erc.europa.eu funded PhD position working in an interdisciplinary team to study #culturalEvolution as a process of reuse, recombination, and creative re-engineering of past solutions. Details 👉 hmc-lab.com/ERCPhDCultur... 🙏Please share!

Fully-funded 4-year #PhD in Cultural Evolution! Join my @erc.europa.eu project exploring how compression & compositionality drive cultural innovation: hmc-lab.com/ERCPhDCultur...
Apply by Nov 12!
Maybe of interest to folks from #COSMOS2025 or @eslr.bsky.social? Please feel free to share! 🙏

Help us strengthen trust in climate scientists in the US! Join our megastudy 👇

If you’re in London next week, why not swing by?

Hello everyone! Along with our first post here on Bluesky, we look forward to the new academic year, hosting our first #LJDM2025 session next week with Dr Simon Ciranka @simyciri.bsky.social. For more info and to keep updated, check our website!

... does this now mean that young people are even LESS uncertainty tolerant, because they listen more to what others say? We have opinions :) Get in touch! Happy to hear yours!

Also, big shoutout of course to @connectedmindslab.bsky.social 🤗

It also means that notions of uncertainty tolerance require additional explanation. It may be that younger people feel unsure about what to choose, which masks as an increased propensity for risky choice at first glance. But at the same time they use social info more, reducing their uncertainty 🤺

This internal uncertainty explains age differences in social influence in our experiment. We manipulated social signals by showing the choices of previous participants to ours. The more uncertain our participants were, the more likely they were to follow others. 🌈 This was true irrespective of age.🌈

Bayesian modelling reveals that younger participants' choices were characterized by greater uncertainty about the utility of choice options, which was distinct from the increased randomness of participants' choices that is usually shown in higher softmax-temperature in younger participants 🤔

We hope to bring more clarity to the notion of uncertainty tolerance among youth 😶‍🌫️. Asking for decisions from description or experience, where uncertainty is low and high, respectively, we demonstrate that adolescents indeed make more risky decisions than adults when uncertainty is high vs low.

Internal uncertainty impacts social information use in risky choice across adolescence - Communications Psychology Adolescents’ choices are influenced by others. A social risky choice experiment and Bayesian modelling reveal that age differences in internal uncertainty, being unsure how to choose, relate to differences in susceptibility to social influence.

😍 Our latest is out now in @commspsychol.nature.com. 🤩 We show with Bayesian modelling and experimental manipulation of uncertainty that developmental differences in social influence depend on differences in the internal uncertainty people have about their choice
doi.org/10.1038/s442...

Did you manage to steal it?

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).

📢 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/...

Very glad to finally share our paper on replay and successor representation learning! ✨

We are hiring for several research positions for this grant, starting early next year. Please reach out if you're interested!
More details on the jobs here: devcompsy.org/wp-content/u...

Abstract: Speed–accuracy trade-offs are a fundamental aspect of decision-making, requiring individuals to balance collecting more information against making faster decisions. Although speed–accuracy trade-offs have been studied at the individual level, their role in human decision-making in social settings remains poorly understood—even though faster, and possibly more error-prone, decisions often have more social influence than slower decisions. We examined how individual differences in speed–accuracy trade-off preferences shape decision-making in pairs, using an interactive online experiment and drift–diffusion modelling. Participants first performed a perceptual task alone, allowing us to estimate their individual drift rates and decision thresholds, the key cognitive determinants of speed–accuracy trade-off preferences. They then performed the task in pairs, sharing decisions in real-time. Pair accuracy depended on the faster (and thus more error-prone) member, and not on the slower (but more accurate) member. Social decisions were not worse than individual ones because faster members increased their thresholds in the social condition and became more accurate, while slower members incorporated less social information. These findings show that individuals adjusted their social information use to the speed–accuracy trade-off preferences of their partners, highlighting the importance of such individual differences for understanding social behaviour.

"Individual differences in speed–accuracy trade-off influence social decision-making in dyads"

🚨Our paper has been published in Proceedings of the Royal Society B doi.org/10.1098/rspb...

w/ Alan Tump @alantump.bsky.social, Ralf Kurvers @ralfkurvers.bsky.social

@royalsocietypublishing.org

1/ 🧵👇

The deadline has been extended until July 16th!

👉 PhDs: hmc-lab.com/ERC_PhDs.html
👉 Postdoc: hmc-lab.com/ERC_Postdoc....

Postdoctoral Researcher in psychology/cognitive science with focus on social learning and cultural evolution Do you want to contribute to top quality medical research? The Mechanisms of Social Behavior lab at the Karolinska Institutet (PI: Björn Lindström) in Stockholm, Sweden is seeking a highly qualified

💥New postdoc position! 💥

Join us to explore how people learn from each other—and how that drives cultural evolution.

Run experiments, build computational models & collaborate across Europe w. @lucasmolleman.bsky.social
📍 Stockholm
More info: shorturl.at/CY4wk

Yay; andrea @andgr.bsky.social is here now too 🚀 :)