Petar Raykov's Avatar

Petar Raykov

@praykov.bsky.social

Cognitive Neuroscientist interested in memory and aging https://www.petarraykov.com/

323 Followers  |  88 Following  |  8 Posts  |  Joined: 13.10.2023  |  1.5072

Latest posts by praykov.bsky.social on Bluesky

So happy to share our paper on the role of the hippocampus as a mismatch detector:
doi.org/10.1073/pnas...

We show that the hippocampus detects mismatches between ongoing experiences and episodic memories but not generalised schematic knowledge.

See 🧡for how we got here:
#neuroskyence #PsychSciSky

04.09.2025 17:06 β€” πŸ‘ 53    πŸ” 13    πŸ’¬ 2    πŸ“Œ 2
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Hippocampal mismatch signals are based on episodic memories and not schematic knowledge | PNAS Prediction errors drive learning by signaling mismatches between expectations and reality, but the neural systems supporting these computations rem...

Now out in PNAS doi.org/10.1073/pnas...

01.09.2025 14:03 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
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New fMRI study shows the hippocampus signals mismatches only when our expectations are based on episodic memories β€” not general knowledge. Challenges theories of the hippocampus as a domain-general comparator. We also explore how brain networks respond to surprise: doi.org/10.1101/2025...

01.09.2025 09:57 β€” πŸ‘ 19    πŸ” 5    πŸ’¬ 2    πŸ“Œ 0
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Complementary MR measures of white matter and their relation to cardiovascular health and cognition - Scientific Reports Scientific Reports - Complementary MR measures of white matter and their relation to cardiovascular health and cognition

New CamCAN study led by @praykov.bsky.social used 11 different white matter (WM) measures to show that WM health is multidimensional: 4 latent MRI-derived factors explained 89% of WM variance, were predicted by vascular health, and predicted cognition: doi.org/10.1038/s415...

29.08.2025 15:02 β€” πŸ‘ 4    πŸ” 2    πŸ’¬ 0    πŸ“Œ 0
Redirecting

This work was done with Chris Bird @chrismbird.bsky.social & Jessica Daly who last year published a review on APOE effects on spatial memory doi.org/10.1016/j.co...

28.02.2025 15:46 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

These results suggest that the APOE4 gene does not directly affect these parts of the brain, and changes may only be seen if adults start to develop Alzheimer’s disease.

28.02.2025 15:46 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
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Importantly, we showed that there were no differences between adults with/without the APOE4 gene. We focused on univariate and connectivity differences during event boundaries; But also examined full-movie/ whole brain functional connectivity and graph-theoretical measures like system-segregation.

28.02.2025 15:46 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Our lab and others have shown that the brain regions that are active when we watch movies overall with regions that are damaged by Alzheimer’s disease. In this study we used MRI brain imaging data collected from 425 people while they watched a short Alfred Hitchcock movie.

28.02.2025 15:46 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Apolipoprotein E e4 (APOE4) is a significant genetic risk factor for Alzheimer’s disease. However, it is not known whether there are differences in the brains of healthy adults who carrying the APOE4 gene.

28.02.2025 15:46 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
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We recently published a new paper investigating APOE effects in Cam-CAN @camcan-2010.bsky.social movie dataset. Examining various measures we failed to find any APOE effects in healthy individuals. You can read more about it in the paper doi.org/10.1177/2398... or the thread below

28.02.2025 15:46 β€” πŸ‘ 7    πŸ” 5    πŸ’¬ 1    πŸ“Œ 0
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Python for Experimental Psychologists: A Fun Way of Learning How to Code Your Experiments and Analyses Python for Experimental Psychologists equips researchers who have no prior programming experience with the essential knowledge to independently script experiments and analyses in the programming langu...

Would you like to learn Python to create experiments and do analyses? BUY OUR BOOK! www.routledge.com/products/978...

This is a new edition for Python 3, with #PsychoPy chapters by @hirstrj.bsky.social and @peircej.bsky.social from @psychopy.org

#cogneuro #psychology #Python #programming

16.12.2024 13:19 β€” πŸ‘ 16    πŸ” 12    πŸ’¬ 2    πŸ“Œ 0
cognestic-2024

Join us for another two weeks of Cognitive Neuroimaging Skills Training In Cambridge, #COGNESTIC, 16-27 September, 2024. We provide training in state-of-the-art methods for open neuroimaging analysis, focussing on MRI, fMRI and EEG/MEG.
www.mrc-cbu.cam.ac.uk/events/cogne...

31.01.2024 16:56 β€” πŸ‘ 8    πŸ” 7    πŸ’¬ 0    πŸ“Œ 1
Theta and alpha oscillations in human hippocampus and medial parietal cortex support the formation of location‐based representations Hippocampus is an international neuroscience journal exploring the hippocampal formation and its interactions with other brain regions.

Very excited that @akulsatish.bsky.social's MEG paper on spatial representations and theta/alpha is officially published in Hippocampus!

Theta and alpha oscillations in human hippocampus and medial parietal cortex support the formation of location-based representations

#neuroskyence #psychscisky

27.03.2024 09:29 β€” πŸ‘ 19    πŸ” 8    πŸ’¬ 0    πŸ“Œ 0
Figure 1: Foraging trial diagram. On each trial participants chose to harvest the tree they were at (down arrow key) or travel to a new tree (right arrow key), during the travel they completed an effortful task, after which they arrived at a new patch with a replenished supply of apples. The tree is a green circle and rectangular brown trunk. The apples are red and lined up in a row on the bottom of the screen. There is a warrior avatar with a shield, helmet, and sword who jumps to harvest the apples.

Figure 1: Foraging trial diagram. On each trial participants chose to harvest the tree they were at (down arrow key) or travel to a new tree (right arrow key), during the travel they completed an effortful task, after which they arrived at a new patch with a replenished supply of apples. The tree is a green circle and rectangular brown trunk. The apples are red and lined up in a row on the bottom of the screen. There is a warrior avatar with a shield, helmet, and sword who jumps to harvest the apples.

I'm elated to share my PhD keystone paper published
@PNAS
www.pnas.org/doi/10.1073/... I've poured my heart & soul into this project since 2016 (8 yrs!) & I'm happy to introduce the Effort Foraging Task to the world #CognitivePsychology #Motivation #Effort #Foraging #DecisionMaking 🧡

26.01.2024 17:58 β€” πŸ‘ 81    πŸ” 45    πŸ’¬ 5    πŸ“Œ 0
Decorative shiny brain image

Decorative shiny brain image

PhD funding alert! A second round of up to 4 School of UK + International Psychology studentships at Sussex this year - deadline 15th Feb.

Application FAQ: t.ly/ZLoEJ - contact potential supervisor/s first to check fit!

For my lab, episodic memory + ageing

#neuroskyence #cognition #psychscisky

26.01.2024 18:05 β€” πŸ‘ 7    πŸ” 9    πŸ’¬ 1    πŸ“Œ 0
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Check out our new paper showing that functional system segregation in fMRI predicts fluid intelligence, but does not meditate the benefits midlife activities have on late life intelligence doi.org/10.1016/j.ne...

11.12.2023 13:41 β€” πŸ‘ 9    πŸ” 3    πŸ’¬ 0    πŸ“Œ 0

Now out in Cognitive Science! We use GPT-2 to show that Bayesian surprise, which tracks changes in the content and confidence of predictions, accounts for human event boundaries in a narrative better than surprisal, which only tracks the predicted probability of individual words tinyurl.com/kd9dpub8

23.10.2023 13:34 β€” πŸ‘ 44    πŸ” 26    πŸ’¬ 2    πŸ“Œ 1

@praykov is following 20 prominent accounts