Lucie Descamps

Fantastic opportunity to do pioneering single-unit recordings from the HUMAN hippocampus and other parts of the brain, with @jorgen-sugar.bsky.social at @uio.no, Norway.

Happy belated publication of some of my PhD work!

Building on our findings that grid field firing rate changes can cause hippocampal remapping and memory impairment, here we show that this effect has a fixed input-output relationship, and we can even predict how place cells will remap!

I’m grateful to all the co-authors that helped this paper see the light of day! Thank you for your support throughout the years ❤️ 10/10

We’re still quite curious about the physics behind the coarse-graining and cell assemblies so @wesleyclawson.bsky.social and I are cooking up a little follow-up paper! 9/10

And surprisingly, assemblies with the most weight in the decoding of position are driven by single-cells displaying a stable object code, suggesting a predictability to which cells would become stable object cells as well as hierarchical coding in the ACC 8/10

Combined with a decoder of neural activity, we demonstrate that both position and behaviour are more linearly separable at a coarser scale, but with similar ensemble sizes, suggesting a generalised coding regime in the ACC 7/10

Some of these population activity maps look pretty cool! Here, using assemblies of 64 neurons 6/10

At the population level, we build cell assemblies at different scales using coarse-graining and show that the representation of the environment, the objects, and behaviour is constant despite dynamic single-cell coding 5/10

Exploratory behaviour of individual mice seem to influence the long-term stability of single-cells: we saw a positive correlation between the overall time spent investigating the objects over 7 days, and the spatial correlation of object cells on Day 1 with their spatial field on Day 7 4/10

We show that whilst there is always a steady proportion of our recorded population coding for objects, very few cells do so reliably, and there is a big day-to-day turnover in this “object cell ensemble”

We used miniscopes and 1P calcium-imaging to record and track over 7 days the activity of excitatory neurons in the ACC while mice were free to explore an environment containing 2 objects 2/10

My first first-author paper is on bioRxiv! Here we ask whether the same subset of neurons in ACC always display object correlates during extensive familiarisation to 2 objects. A short 🧵1/10