AI can learn to navigate like animals by using place cells, a type of brain cell that encodes spatial information. This mimics the way that mammals learn to navigate their environment. The research could lead to better AI systems and a deeper understanding of animal cognition.

#AI #navigation #placecells

https://neurosciencenews.com/place-cell-ai-learning-23202/

Spike-sorting, before /after

This uses the automated method Klustakwick and then some manual refinement

#PlaceCells #SpikeSorting #Tetrodes #Neuroscience

New review on the “spatial cells” across different species! Looks very interesting:
Neural mechanisms for spatial cognition across vertebrates
Vinepinsky & Segev 2023

Small but important comment: it is perfectly normal for place cells to have multiple #PlaceFields ! Only in very small environments (<80cm diameter) will you mostly see single-field place cells. The single field is probably more the exception than the rule in the natural world.

#NeuroPaper #Review #Neuroscience #PlaceCells #HeadDirectionCells #GridCells #BVCs #CrossSpecies

So... what are the differences between #ThetaSequences and #Replay (in the rodent #Hippocampus ?

Here is an illustration from real data!

Fig 1 shows ~70 #PlaceCells firing while a rat runs on a maze to reach a reward. See how the activity is different between running and pausing?
Fig 2 shows possible theta sequences.
Fig 3 shows possible replay.

Spot the differences & check alt text for more info!

PS: (very simple) #Matlab code to plot this is available here !

1/2

⤵️​3/5 Why P1 (‘Place cells in the 4-room’):

• Has #Rat SaloonDoors & bells
• Rats rapidly learn to avoid uncued locked doors
• Rats do flexible detours (most of the time) -> #CognitiveMap use?
• #PlaceCells do not remap to changes in connectivity: spatial, but not topological?
• They also do not over-represent doors!
• Place cells can represent space globally (individually and as a population) even when geometry repeats

🔗​https://www.sciencedirect.com/science/article/pii/S0960982221000385

@biorxivpreprint
⬆️ Check this new preprint from the Rondi-Reig team! Looks pretty interesting 👀​

#Hippocampus #Cerebellum #Foraging #PlaceCells #Mice #NeuroPaper

https://www.biorxiv.org/content/10.1101/2023.02.04.526971v1

@biorxivpreprint@qoto.#PlaceCells #Hippocampus

The latest episode of Hippocampal History Tour (by @nadel ) is such a treat!! It really makes you live the period of the discovery of #PlaceCells, as if you were there... the incredulity, even amusement at first.. and then the realization, by experience, that it is a thing, and the ensuing fascination 🤯​

Also John Kubie & Bob Muller are always getting so much praise, they must have been such great colleagues to work along! I wish John joined us on Mastodon!

https://neuromatch.social/@nadel/109711180400409516 (in 3 parts)

@dlevenstein Sounds like Overdispersion (used mostly for #PlaceCells as far as I know)!
See for example:
Fenton et al., 1998: https://pubmed.ncbi.nlm.nih.gov/9501237/
Olypher et al., 2002: https://pubmed.ncbi.nlm.nih.gov/12031343/
Fenton et al., 2010: https://www.jneurosci.org/content/30/13/4613

RT @rmgrieves
Really cool review paper on "splitter cells" in the hippocampus with @ElDuvelle and @mattmizumi out now!

Temporal context and latent state inference in the hippocampal splitter signal: https://doi.org/10.7554/eLife.82357

#hippocampus #brain #PlaceCells

@nadel Another amazing episode! So clearly written and interesting. Thank you so much again for sharing.
Adding some hashtags to help this gem being discovered:

#HippocampusGurus #HippocampusHistory #hippocampus #PlaceCells #EntorhinalCortex #GridCells

RT @rmgrieves
Really cool review paper on "splitter cells" in the hippocampus with @ElDuvelle and @mattmizumi out now!

Temporal context and latent state inference in the hippocampal splitter signal: https://doi.org/10.7554/eLife.82357

#hippocampus #brain #PlaceCells

Hi all 😃​
Our latest #Review on #SplitterCells is now published in @eLife !!
I will probably write a real thread on it when I get a chance... for now:

link: https://elifesciences.org/articles/82357

why: some neurons in the #Hippocampus (and other brain regions) of #Rats (and other mammals) have the fascinating ability to discriminate not just different presents, but different past or future states or trajectories in the same current situation. They could be related to #EpisodicMemory or #DecisionMaking 🤔​They are called 'trajectory-dependent cells' or Splitter Cells. 🔀​ We tried to make sense of them!

what: Hippocampal Splitter cells do a lot of puzzling stuff. For example there's a lot of them even in tasks that do not require the Hippocampus to be solved. They spread asymmetrically on a linear track leading to a choice point - 'past' splitters around the start and 'future' splitters towards the choice point. #TimeCells cells can be splitter cells (but they're usually #PlaceCells). Splitter cells evolve with experience, or maybe it is performance, nobody really knows. ​⁉️​ ... and a lot more weird stuff

conclusion: Two different computational models, the temporal context model and the latent state model, each explain a subset of the properties of splitter cells... so perhaps the Hippocampus implements both! But more experiments are needed to disentangle them 😄​

now what: questions or comments? Please let us know!! ✍️​

#Neuroscience #Cognition #NeuroPaper

Check this new #Preprint in #Chickadees:
“An entorhinal-like region in food-caching birds”

https://www.biorxiv.org/content/10.1101/2023.01.05.522940v1

“We found a well-delineated structure in these birds that is topologically similar to the entorhinal cortex and interfaces between the hippocampus and other pallial regions. Recordings of this structure revealed entorhinal-like activity, including border and multi-field grid-like cells.”

(I didn’t see any grid-like cells but it looks very interesting nonetheless!!)

#Hippocampus #EntorhinalCortex #PlaceCells #BorderCells

Does anyone remember that #Neuroscience #Paper in #Rats where they had a choice between several maze arms with different reward values? And sometimes the arm positions changed?
There was a version with #PlaceCells (I think) about 5 years ago and a newer version with replay (?) maybe last year… 🙏

New paper possibly demonstrating time encoding for another bat... Could be my first #MastoJC (journal club) if I get some time to read it!
If you've read it: what do you think??

https://www.nature.com/articles/s41593-022-01226-y

#PlaceCells #TimeCells #Hippocampus #Bats

#Introduction
Hi all, I'm a spatial cognition postdoctoral researcher and will post about rats (like these), #PlaceCells (yes it's a new hashtag) and other cool things that the #Hippocampus does, as well as random stuff.

If I have bad habits from "that other site", please help me correct them, and as a Mastodon newbie, do send me your tips or tutorials!

PS: do rats need content warning?

Joining the #chatGPT party asking it to explain #placecells like #taylorswift would