@peterdoohan.bsky.social
⚠️PREPRINT ALERT⚠️ How can we better understand distributed brain activity across temporal and spatial scales? In this collaborative project, we combined ultra-flexible electrodes with two-photon imaging to illuminate brain-wide neural dynamics. Link: doi.org/10.21203/rs.... 1/8
Congrats @jespass.bsky.social on her new paper! PFC is widely thought to talk to HPC via nucleus reuniens - but no one has tested if this actual connectivity exists. Turns out it's wired to block it: PFC inputs to reuniens contact only neurons projecting back to PFC, not ones projecting to HPC. 🧪🧠📈
Nucleus reuniens is organised as parallel circuits rather than a prefrontal-hippocampal relay
Interactions between the prefrontal cortex (PFC) and hippocampus (HPC) are crucial for flexible and memory guided behaviour. Because there are no direct projections from PFC to HPC, it is widely presu...
biorxiv.org
Nucleus reuniens is organised as parallel circuits rather than a prefrontal-hippocampal relay https://www.biorxiv.org/content/10.64898/2026.08.11.744129v1
Now in Science: How does the brain’s navigation system allocate its limited representational resources during behavior? We found that grid cells sweep toward locations of interest, providing a potential mechanism for allocating spatial attention in the cognitive map.🧵 science.org/doi/10.1126/...
Kevin Mitchell @wiringthebrain.bsky.social talks to Timothy Behrens @behrenstimb.bsky.social about which neural systems the field has genuinely cracked. #neuroskyence www.thetransmitter.org/computationa...
Success stories from computational neuroscience
Kevin Mitchell talks with Timothy Behrens about ring attractors, the role of innate structure, and an expanded view of cognitive maps.
thetransmitter.org
For 30 years, neuroscientists have argued about whether theta sweeps are just passive sensing, or something closer to planning. So which is it? #neuroskyence By @natmesanash.bsky.social www.thetransmitter.org/memory/new-f...
New findings begin to resolve theta sweep debate
Theta sweeps have been mired in controversy for decades, but the emerging consensus view suggests that they function in attention and goal direction.
thetransmitter.org
New preprint! www.biorxiv.org/content/10.6... Nearly a decade after starting the project, the first major results from our comparative connectomics work is online! Comparing the head direction circuits of the central complex in bees, ants and flies, recapitulating >300million years of evolution.
***New preprint from the lab*** showing “Generative replay across hippocampal-neocortical circuits”. In sleep we show spiking sequences in V1 (sensory neocortex!) that represent information that has not been directly experienced www.biorxiv.org/content/10.6... @bndu.ox.ac.uk @ndcnoxford.bsky.social
Generative replay across hippocampal-neocortical circuits
To make flexible decisions, the brain needs to make inferences between events that were not directly experienced together. In sharp-wave ripple (SWR) events, during periods of rest and sleep, spiking ...
biorxiv.org
📜 Project Showcase 🛠️ pyControl: Open source, Python-based, behavioural experiment control. 👩💻 🧑💻 Developed by Thomas Akam 👀 To learn more about it: open-neuroscience.com/en/post/pyco... #OpenSoftware #OpenScience #OpenSource
Our work on goal-directed theta sweeps is out! We found two different types of theta sweeps in the rat hippocampus. During random foraging, left-right alternating sweeps dominated (Vollan, 25). However, during memory-guided navigation sweeps pointing to hidden goal locations emerged with learning.
Beautiful! Hippocampal theta sweeps are biased towards sampling more promising futures 🧹📍
Neil Burgess@neilburgess10.bsky.social · 3mo agoEver wondered how the hippocampal cognitive map is read-out? @changmin-yu.bsky.social @zilong-ji.bsky.social with Jake & John, show that, during navigation, theta sweeps indicate remembered goal-directions (cf. current/next movements or perceptual targets) 1/2 www.nature.com/articles/s41...
How does the human brain extract abstract structure from experience? We show that sensory-independent relational representations emerge in mPFC over several days. Work with @mgarvert.bsky.social and @behrenstimb.bsky.social now out in @currentbiology.bsky.social: www.cell.com/current-biol...
Good scientist, terrible designer? We feel you. Inspired by MetBrewer, the palette chooser for the connoisseurs, @sandra-neuro.bsky.social and I present EraBrewer: great looking colours for us Swifties! github.com/mathias-sm/E... cran.r-project.org/web/packages...
This makes some fun experimental predictions ... 👀📈 @lpriestley.bsky.social
Thomas Akam@thomasakam.bsky.social · 3mo agoWhy does dopamine ramp up during approach to predictable rewards? In this preprint with Luke Priestley, we explore the idea that dopamine ramps occur when reward predictions inferred using a world-model are used to train striatal cached values.
This is one of the coolest things I have been involved with. Truly flexible navigation in mice. Real insight into how mPFC computes the plans. Great fun to see what PFC is doing with those hippocampal theta sweeps. From the awesome @peterdoohan.bsky.social and (now on bsky) @thomasakam.bsky.social
@peterdoohan.bsky.social · 3mo agoHow do brains plan actions towards goals? To get at this question we studied mice navigating complex mazes as goals changed on every trial 🧵 Work with @thomasakam.bsky.social @behrenstimb.bsky.social @kristorpjensen.bsky.social now on BioRxiv: www.biorxiv.org/content/10.6...
This paper is so cool that it’s finally convinced @thomasakam.bsky.social to join Bluesky
@peterdoohan.bsky.social · 3mo agoHow do brains plan actions towards goals? To get at this question we studied mice navigating complex mazes as goals changed on every trial 🧵 Work with @thomasakam.bsky.social @behrenstimb.bsky.social @kristorpjensen.bsky.social now on BioRxiv: www.biorxiv.org/content/10.6...
This project builds on work establishing the behaviour done at Champalimaud in Lisbon with @michaelfsp.bsky.social, Beatriz Godinho, Christian Machens, and @ruimcosta.bsky.social : www.biorxiv.org/content/10.6...
Flexible route planning and rapid structure learning by mice in complex environments
Action selection using predictive models of the environment plays a fundamental role in human and animal behaviour, yet is poorly understood at circuit and algorithmic levels. Spatial navigation is an...
biorxiv.org
It has been super fun to work on this, where we learned that: 1) Mouse PFC is needed for model-based override of habits. 2) Separate PFC populations encode a 'policy' and the current 'value'. 3) The policy and value codes alternate theta sweeps towards the goal. ...and much much more!
@peterdoohan.bsky.social · 3mo agoHow do brains plan actions towards goals? To get at this question we studied mice navigating complex mazes as goals changed on every trial 🧵 Work with @thomasakam.bsky.social @behrenstimb.bsky.social @kristorpjensen.bsky.social now on BioRxiv: www.biorxiv.org/content/10.6...
How do brains plan actions towards goals? To get at this question we studied mice navigating complex mazes as goals changed on every trial 🧵 Work with @thomasakam.bsky.social @behrenstimb.bsky.social @kristorpjensen.bsky.social now on BioRxiv: www.biorxiv.org/content/10.6...
Come see what grid cells do on complex mazes tonight at #cosyne2026 :) @charlesdgburns.bsky.social
Tim Behrens@behrenstimb.bsky.social · 6mo agoSession Title: [1-036] Regular Hexagonal Grid Cell Maps in Complex Environments. Thursday -> Tonight!! @peterdoohan.bsky.social, Charles Burns If you change the transistion statistics of the world, do the grid cells represent the new transitions (like eigen-SR), or do they stay as hexagons?
Excited to see this Version Of Record of my work out in @elife.bsky.social! elifesciences.org/articles/106... We investigate the mental representation of geometric shapes in adults and children using fMRI and MEG. Each figure has a video of me explaining the figure: go and read it, or read below.
Out today in Neurophotonics, we show that cross-talk between the imaging laser and opsin in all-optical experiments can affect response dynamics beyond what has been accounted for. Imaging conditions subthreshold for evoking spikes can accelerate opsin desensitization: doi.org/10.1117/1.NP...
doi.org
1/n: A new collaborative preprint from the lab to start the year: "A multi-ring shifter network computes head direction in zebrafish" together with Siyuan Mei, Martin Stemmler and Andreas Herz from the LMU, Munich.
1/ Excited to share that our symposium review covering cognitive mapping in the PFC just came out in the Journal of Neuroscience: www.jneurosci.org/content/45/4...
Cognitive Maps in the Prefrontal Cortex
The prefrontal cortex (PFC) is critical for our ability to rapidly and flexibly adapt our behavior in new environments based on our previous experience. Despite its importance, the neural substrates a...
jneurosci.org
Come join us at #SfN25 for the minisymposium "Cognitive Maps in the Prefrontal Cortex"! Saturday, Nov 15, 2:00-4:30pm, Room SDCC 6CF www.abstractsonline.com/pp8/#!/21171... We will explore how the PFC represents structured relationships across species and how this supports flexible behavior.
🚨New pre-print!🚨 Can we truly independently read and write neuronal activity at the same time using all-optical techniques? Here we show that even two-photon imaging over large fields of view with low dwell time per cell can bias neural dynamics! Read on for some potential fixes: (1/5)
Desensitization of opsin responses during all-optical interrogation depends on imaging parameters
Significance The combination of two-photon calcium imaging and two-photon optogenetic stimulation, termed all-optical interrogation, provides spatial and temporal precision when recording and manipula...
biorxiv.org
** We have up to TWO funded PhD positions available in our lab!! Apply below to find new ways to enhance memory👇 Pls retweet ** Deadline: 2nd December 1. Cross-species closed-loopTMR: tinyurl.com/bddu4tp6 2. TUS and TMR in humans: tinyurl.com/jjws5ctj Happy to chat to interested applicants.
Enhancing memory using cross-species closed-loop Targeted Memory Reactivation | mrcbndu
tinyurl.com
Twenty-four years ago today, our paper “A forkhead-domain gene is mutated in a severe speech and language disorder” was published: www.nature.com/articles/350.... A personal thread about the ups & downs of the journey we took to get to that point....1/n 🗣️🧬🧪
