iiinova — where your digital self keeps evolving

Caitlin Mallory @caitlinmallory.bsky.social · 15/11/2025

Come hang out with me tomorrow afternoon at poster JJ5! I'll be sharing new work investigating how replay features like rate of occurrence, speed and self-avoidance change dynamically with learning at behaviorally relevant locations

050

Caitlin Mallory @caitlinmallory.bsky.social · 04/11/2025

My 4 year old just showed me the "book" she made at school explaining, "here's your book, I hope you like it. Don't forget to subscribe!"

010

Caitlin Mallory @caitlinmallory.bsky.social · 21/10/2025

I was in tears after a rough science day until my 4 year old hugs me and says "at least you have a great kid!"

010

Reposted by Caitlin Mallory

Angelo Forli @aforli89.bsky.social · 24/09/2025

Interested in the brain, circuits, and behavior? Enjoy tinkering and asking bold questions in neuroscience? The Forli Lab (IIT, Genova, Italy) is hiring! 🧠 🔬 🟩◻️🟥->🍕🚫🍍 Check out our website for updates: sites.google.com/view/forli-lab

33119

Reposted by Caitlin Mallory

Sam Gershman @gershbrain.bsky.social · 19/09/2025

This is one of the most outstanding examples of circuit understanding I've seen in a long time. The unification of theory and experiment is beautiful. When Malcolm presented this in my lab, the audience was cheering at the end, and one person shouted (non-ironically) "You did it!"

510621

Caitlin Mallory @caitlinmallory.bsky.social · 19/09/2025

Congratulations Malcolm!!! Can't wait to read :)

010

Reposted by Caitlin Mallory

Malcolm Campbell @malcolmgcampbell.bsky.social · 07/08/2025

Our paper on foraging is now published in Neuron! Read it here: www.cell.com/neuron/fullt... This project was co-led by Michael Bukwich (not on Bluesky) and me, with major contributions from all co-authors. Huge thanks to the whole team!

cell.com

Competitive integration of time and reward explains value-sensitive foraging decisions and frontal cortex ramping dynamics

Bukwich and Campbell et al. show that mice integrate elapsed time and reward intake, scaled by a latent patience variable, to decide when to leave virtual “patches.” Frontal cortex ramping activity ma...

28322

Reposted by Caitlin Mallory

UC Davis Physiology @ucd-physiology.bsky.social · 19/06/2025

Congratulations to all the amazing scientists named 2025 Freeman Hrabowski Scholars by HHMI. We’re immensely honored to have two #PMB faculty members, @doctheagrif.bsky.social and @elisazhang.bsky.social , among this inspiring group. An incredible and well-deserved achievement! @ucdavis.bsky.social

hhmi.org

The 2025 Freeman Hrabowski Scholars | HHMI

Freeman Hrabowski Scholars are outstanding early career faculty who have the potential to become leaders in their research fields.

1277

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

Ha, it most definitely is. When you do get a chance, let me know what you think!

010

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

19/19 And of course, a huge thank you to my postdoc mentor, David Foster, for his guidance and invaluable input along the journey! I welcome your thoughts and would love to chat with anyone about our findings!

030

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

18/19 John had conceived of similar adaptation models of replay and theta sequences before. When we teamed up to look at whether a neuronal fatigue model could explain replay's perplexing ‘past-avoidance’, everything began to click into place.

130

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

17/19 This project unfolded like a fun but super challenging puzzle. For a long time we wondered, why would replay avoid the recent past? I want to give a HUGE shout out to co-author John Widloski for his tremendous contribution in helping put the final pieces together.

120

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

16/19 When we added a source of facilitation onto cells that had been activated along the animal’s prior path, we were able to subtly increase the rate of retrospective replays overall and recapitulate the eventual emergence of a past bias.

130

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

15/19 The model produced replays that both avoided each other and the animal’s recent past (for a period of time related to time constant adaptation). Notably, without an additional input (presumably from MEC), the model did not produce the eventual bias for past-going replays.

120

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

14/19 Finally, we considered whether a recurrent network endowed with neuronal fatigue could recapitulate this counterintuitive organization of replay. We found that, in our model, adaptation not only *generates* replay, but it also organizes it.

130

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

13/19 We optogenetically (or chemogenetically) shut down MEC as rats consumed reward. We indeed found that retrospective replays became less frequent with MEC suppressed, although they were not altogether abolished.

130

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

12/19 How does the prior path eventually become preferentially replayed later in the stopping period? We wondered whether the medial entorhinal cortex, a cortical region highly interconnected with hippocampus, might play a role in biasing replay for the animal’s recent past.

120

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

11/19 This made us wonder, would *replay* of a path also fatigue the participating cells and prevent a subsequent replay of the same path? Consistent with the idea, we found that when two replays occur back-to-back (within about 1 sec), the second replay avoids the first.

150

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

10/19 We hypothesized that neuronal fatigue effectively takes recently activated place cells ‘out of commission’ for a few seconds. If replay is going to occur after the animal stops, it has to recruit different cells/represent a different path from that just taken.

250

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

9/19 So, which did we observe? Clearly, the latter- when the past and future paths overlapped, replay avoided them both for the first few seconds.

150

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

8/19 But sometimes rats turned around, retracing their steps so that the future and past paths overlapped. In this particular case, future-preferring versus past-avoiding replays would point in opposite directions.

150

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

7/19 We suspected that the primary factor influencing replay’s direction in the first few seconds after stopping is ‘past-avoidance’, rather than ‘future-preference'. This can be hard to distinguish, since rats often continue moving in the same direction after pausing.

140

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

6/19 But now you can more easily see that what changes most dramatically over the stopping period is the angle of replays relative to the animal’s past path. It starts off large and decreases with a time course that is strikingly similar across subjects…

140

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

5/19 Here’s another way of visualizing the open field data, considering ALL replays. Every replay contributes 2 points to the bottom left plot: an angle relative to the rat’s future path (green) and an angle relative to the rat’s past path (purple). This tells a similar story.

130

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

4/19 Do replays in the open arena also change over the stopping period? We classified replays strongly aligned with the rat’s future path as ‘prospective’ and those strongly aligned with his past as ‘retrospective’. Strikingly, prospective replays preceded retrospective replays.

150

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

3/19 We noticed a surprising and highly consistent organization of hippocampal replay. On the linear track, forward replays of the rat’s upcoming path preceded reverse replays of his past path.

150

Caitlin Mallory @caitlinmallory.bsky.social · 31/01/2025

2/19 We discovered a strict organization to awake hippocampal replay that we believe provides key evidence that replay is generated through a mechanism involving neuronal fatigue. This organization also has implications for replay's role in memory and behavior.

150

Reposted by Caitlin Mallory

Hongyu_Chang @hongyuchang.bsky.social · 02/01/2025

SEEING THROUGH YOUR EYES 👁️: Excited to share our new paper (which is out now @nature.com !!) with Wenbo Tang, Antonio Fernandez-Ruiz✉️, and Azahara Oliva✉️: we discovered a novel sleep microstructure that promotes memory replay! #Neuroscience #hippocampus nature.com/articles/s41... 🧵 1/12👇

nature.com

Sleep microstructure organizes memory replay - Nature

The temporal microstructure of the brain can multiplex distinct cognitive processes during sleep to support continuous learning.

410431

Caitlin Mallory @caitlinmallory.bsky.social · 28/12/2024

I showed my 3 year old The Lion King once and now she's using "Hakuna Matata" as though it means "YOLO". I'm like, Sadie, don't jump off that ledge, you could really hurt yourself!" and she's like "Mama (sigh) Hakuna Matata".

160