Şahcan Özdemir
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sahcan.bsky.social
Şahcan Özdemir
@sahcan.bsky.social
sahcanozdemir.github.io | PhD candidate | cognitive neuroscience | working memory | attention| action planning
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1/4 I’m really excited to share that my first PhD manuscript has been accepted for publication in the Journal of Neuroscience 🎉! Until it becomes available, don’t forget to check out our updated preprint (with some additional insights) #JNeurosci
Preprint Alert!!

In our latest study, we describe a novel relationship between action planning and working memory. Our results show that action-item associations affect how working memory maintains the fidelity of sensory information during a task.

Check it out: www.biorxiv.org/content/10.1...
Motor control processes moderate visual working memory gating
Gating processes that regulate sensory input into visual working memory (WM) and the execution of planned actions share neural mechanisms, suggesting a mutual interaction. In a preregistered study (OS...
www.biorxiv.org
Reposted by Şahcan Özdemir
🎉 My first first-author paper was just accepted in JEP:HPP! We asked what “active” vs “passive” WM states do - do they protect against interference? Across 4 behavioural experiments we find no reliable protection. Updated preprint here: doi.org/10.1101/2024.02.05.578913 @elkanakyurek.bsky.social
Feature and space-based interference with functionally active and passive items in working memory
Functionally active and passive states in working memory have been related to different neural mechanisms. Memoranda in active states might be maintained by persistent neural firing, whereas memoranda in passive states might be maintained through short-term synaptic plasticity. We reasoned that this might make these items differentially susceptible to interference during maintenance, in particular that passively maintained items might be more robust. To test this hypothesis, we gave our participants a working memory task in which one item was prioritised (active) by always probing it first, while the other item was deprioritised (passive) by always probing it second. In two experiments, on half the trials, we presented an interfering task during memory maintenance, in which the stimuli matched either the feature dimension of the memory items (colour or orientation), or their spatial location. Whether the interfering task appeared on a given trial was unpredictable. In a third experiment where participants were given prior knowledge of the interference condition, and finally in a fourth experiment we used a reward-based prioritisation cue. Across experiments, we found that both active and passive memory items were affected by interference to a similar extent, with overall performance being closely matched in all experiments. We further investigated precision and probability of target response parameters from the standard mixture model, which also showed no differences between states. We conclude that active and passive items, although potentially stored in different neuronal states, do not show differential susceptibility to interference. ### Competing Interest Statement The authors have declared no competing interest.
doi.org
January 27, 2026 at 4:23 PM
Reposted by Şahcan Özdemir
How does prior knowledge affect the way we experience the world?

In our new paper, we show that prior knowledge can both increase and decrease how often experience is segmented into events.

link.springer.com/article/10.3...
Ignorance is bliss: Exploring the dual role of knowledge in event segmentation - Psychonomic Bulletin & Review
Episodic memories are segmented. This study explores the dual role of prior knowledge in event segmentation, hypothesizing that knowledge leads to coarser segmentation when experiences align with it, ...
link.springer.com
January 21, 2026 at 11:02 AM
Reposted by Şahcan Özdemir
Here’s a thought that might make you tilt your head in curiosity: With every movement of your eyes, head, or body, the visual input to your eyes shifts! Nevertheless, it doesn't feel like the world does suddenly tilts sideways whenever you tilt your head. How can this be? TWEEPRINT ALERT! 🚨🧵 1/n
a husky puppy is laying on the floor with its tongue out and wearing a blue collar .
ALT: a husky puppy is laying on the floor with its tongue out and wearing a blue collar .
media.tenor.com
January 21, 2026 at 12:28 PM
Just tell me a thriller that exceeds ‘two scientists travelling to the Austrian Alps to meet a cow who uses a stick to scratch her back'!
Our new paper (with @biotay.bsky.social) is out and on the cover story of @currentbiology.bsky.social !!!! Veronika, a Carinthian mountain cow flexibly uses a “multi-purpose tool” to scratch herself. A video and more information will follow in the comments.
www.cell.com/current-biol...
January 20, 2026 at 1:39 PM
Reposted by Şahcan Özdemir
It won't actually exist for another month or so, but because it now 'exists' on amazon, I'll humbly observe that, after working through this book, your student/trainee would be able to read and understand all but two or three papers in this week's J. Neurosci. Check it out:
January 16, 2026 at 10:38 PM
Reposted by Şahcan Özdemir
🚨 #Preprint alert 🚨 A multilab study led by Claire Vanbuckave investigated whether the strength of pupil responses to imagined brightness/ darkness reflect differences in vividness of mental imagery. We found … 👇 1/3 🧵 #psychology #aphantasia #pupillometry #mentalimagery
doi.org/10.64898/202...
Pupil size reflects moment-to-moment fluctuations in mental imagery, but not (or hardly) individual differences in imagery
Previous research has shown that the eyes' pupils are larger when imaging dark as compared to bright objects or scenes. Based on this, it has been claimed that pupil size is a sensitive marker of ment...
doi.org
January 15, 2026 at 9:52 AM
Reposted by Şahcan Özdemir
With some trepidation, I'm putting this out into the world:
gershmanlab.com/textbook.html
It's a textbook called Computational Foundations of Cognitive Neuroscience, which I wrote for my class.

My hope is that this will be a living document, continuously improved as I get feedback.
January 9, 2026 at 1:27 AM
Reposted by Şahcan Özdemir
I think this is a key point for our field to reckon with – that the underlying cognitive representation can vary across the many tasks and conditions that we use to probe working memory. I think that doesn't mean we give up our search – we do have to rethink the questions we are asking though!
In summary, this combination of compositionality and task dependence means that, as scientists, we cannot find a “fundamental” working memory format. Any changes we make to an experiment to zero-in on the memory will also change the memory itself! (19)
a brown dog is sitting on a couch holding a gift box
Alt: a brown dog is sitting on a couch and tilting its head in confusion
media.tenor.com
January 6, 2026 at 10:05 PM
Reposted by Şahcan Özdemir
We recently published a theoretical review about how compositional and generative mechanisms in working memory provide a flexible engine for creative perception and imagery.

Pre-print:
osf.io/preprints/ps...

Paper: www.sciencedirect.com/science/arti...
January 6, 2026 at 7:04 PM
Reposted by Şahcan Özdemir
Talking today about whether attention can modulate retinal activity, come join! 👁️ #nvp25
This afternoon at #nvp2025, an entire session on cognitive #pupillometry 👁️ with talks by @anavili.bsky.social , @cstrauch.bsky.social and others. See you at 👉 12:00! #psychology
December 18, 2025 at 9:14 AM
Reposted by Şahcan Özdemir
Our new preprint is out!

Using a continuous-report paradigm, we show that divided attention reliably disrupts long-term memory retrieval by reducing accessibility—not precision.

Two experiments + mixture modeling + TCC.

Link: osf.io/preprints/ps...
OSF
osf.io
December 9, 2025 at 3:56 PM
Reposted by Şahcan Özdemir
Do you have an open working memory dataset and want it to be findable and reused? You can now add it to the Open WM Data Hub: williamngiam.github.io/OpenWMData! The collection of datasets tagged with useful metadata is steadily growing thanks to a small team of volunteers!
OpenWMData
A collection of publicly available working memory datasets
williamngiam.github.io
December 1, 2025 at 11:28 PM
I am really thrilled to be a part of this study! Don't miss the preprint!! 🎉
🚀 New preprint alert 🚀

How easily can working memory create interference in long-term memories? Our new preprint, Interference Across Memory Systems: Disrupting Long-Term Memories Through Working Memory examines this
osf.io/preprints/ps...

w/ @sahcan.bsky.social Anna Lena Mantei, Daniel Schneider
OSF
osf.io
November 18, 2025 at 10:00 AM
Reposted by Şahcan Özdemir
Now out in #ScienceAdvances: @baiweiliu.bsky.social and I ask how internal (goal) and external (sensory) selection are coordinated during visual search. The key insight: internal and external selection are not inherently serial, but may develop in parallel in the human brain: doi.org/10.1126/scia...
Concurrent selection of internal goals and external sensations during visual search
Internal and external selection processes can codevelop in time to yield efficient search behavior.
doi.org
November 10, 2025 at 12:00 PM
Reposted by Şahcan Özdemir
Understanding the flexibility of working memory: Compositionality, generative processing, anchors and holistic representations
www.sciencedirect.com/science/arti...
#neuroscience
Understanding the flexibility of working memory: Compositionality, generative processing, anchors and holistic representations
The typical conception of working memory is a mechanism to temporarily hold multiple discrete objects in service of other cognitive tasks in an item-b…
www.sciencedirect.com
October 25, 2025 at 12:45 PM
Reposted by Şahcan Özdemir
Any early-career researchers in #workingmemory wanting to contribute to an #openscience initiative? I'm looking for help building up a data hub resource for the field. Volunteers can expect to devote a few hours, and might pick up insights into handling research data and how to use Github.
OpenWMData
A collection of publicly available<br>working memory datasets
williamngiam.github.io
October 22, 2025 at 1:56 AM
Reposted by Şahcan Özdemir
New preprint!

Working memory contents can be decoded from alpha band power. But does working memory maintenance really depend on these oscillations?

We say no, because we found that alpha power decoding only works for prioritized items, not deprioritized ones. 1/3

www.biorxiv.org/content/10.1...
Sustained alpha oscillations serve attentional prioritization in working memory, not maintenance
Recent theory on the neural basis of working memory (WM) has attributed an important role to "activity-silent" mechanisms, suggesting that sustained neural activity might not be essential in the reten...
www.biorxiv.org
October 17, 2025 at 11:27 AM
Reposted by Şahcan Özdemir
CDS Asst. Prof. @neurograce.bsky.social has launched a YouTube channel, “5 Minute Papers on AI for the Planet,” translating climate-AI research into short video explainers, inspired by her course at CDS, “Machine Learning for Climate Change.”

nyudatascience.medium.com/cds-grace-li...
CDS’ Grace Lindsay Launches YouTube Channel on “AI for the Planet”
Grace Lindsay’s new YouTube series turns climate-AI research into five-minute videos for a wide audience.
nyudatascience.medium.com
October 8, 2025 at 5:36 PM
Reposted by Şahcan Özdemir
The final part of my PhD work is now published in JEP:LMC 🤩 Special thanks to my wonderful PhD supervisors @evievergauwe.bsky.social and @nlangerock.bsky.social 🤗 psycnet.apa.org/fulltext/202...
October 8, 2025 at 9:25 AM
Reposted by Şahcan Özdemir
The human-neuroscience N2pc marker of covert and internal attention co-occurs with spatial biases in microsaccades, 200-300 ms after prompted to shift attention. (How) are these empirical phenomena related? Check it out in the latest work led by @baiweiliu.bsky.social:
doi.org/10.1371/jour...
Microsaccades strongly modulate but do not directly cause the EEG N2pc marker of spatial attention
Researchers often study human attention using microsaccades and the N2pc EEG marker, but it is unclear to what extent microsaccades contribute to N2pc. This study shows that microsaccades modulate N2p...
doi.org
October 7, 2025 at 6:59 AM
Reposted by Şahcan Özdemir
I set out to write the book that I would want to read. The result is Een Wereld vol Denkers (A World of Thinkers) Here’s how and why the book came to be! 🤩✍️ cogsci.nl/blog/my-expe... #booksky #popularscience #psychology #ai #eenwereldvoldenkers @theodanes.bsky.social @uitgeverijbalans.bsky.social
My experiences writing and publishing popular science // Cogsci
cogsci.nl
October 1, 2025 at 4:58 PM
Reposted by Şahcan Özdemir
We’re looking for a postdoc to join our Max Planck group in Germany some time in 2026. If you have computational and/or neuroimaging expertise, and are interested in questions intersecting perception and cognition, please reach out! I’ll also be happy to chat at the #Bernsteinconference this week.
September 29, 2025 at 5:15 PM
Reposted by Şahcan Özdemir
The IfaDo sessions have become really a community staple and I am very glad to be able to chip in.
On the 23rd of September we will welcome @tbchristophel.bsky.social for our IfADo colloquium at 16:00 (CET). The event is hybrid and open online. You can reach me out for Zoom invitation, or use the following link to sign up for both the link and our email list.
www.ifado.de/en/press/eve...
September 17, 2025 at 11:17 AM
Reposted by Şahcan Özdemir
On the 23rd of September we will welcome @tbchristophel.bsky.social for our IfADo colloquium at 16:00 (CET). The event is hybrid and open online. You can reach me out for Zoom invitation, or use the following link to sign up for both the link and our email list.
www.ifado.de/en/press/eve...
September 17, 2025 at 9:39 AM
On the 23rd of September we will welcome @tbchristophel.bsky.social for our IfADo colloquium at 16:00 (CET). The event is hybrid and open online. You can reach me out for Zoom invitation, or use the following link to sign up for both the link and our email list.
www.ifado.de/en/press/eve...
September 17, 2025 at 9:39 AM