Cantin Ortiz

Our findings suggest a hierarchical model of sensory processing, where sensory cortices act as continuous input providers while the entry stage of the hippocampus, the dentate gyrus, acts as an on-off-switch for task relevance.

Alt: Two panels showing the decoder performance. On the top, during active navigation, the decoder performs significantly better with real than shuffled data, in V1 and DG, and in the A-B and A-A’ pair of environments. On the bottom, during passive exposure, the decoder performs above chance in V1 in both A-B and A-A’, but there is no statistical difference between real and shuffled data in the dentate gyrus.

We computed decoding chance level by randomly shuffling laps labels. This revealed that the visual cortex maintained a high sensory discrimination regardless of behavioural engagement, whereas the dentate gyrus required active navigation for effective discrimination.

Alt: A panel illustrating the principle of the decoder. Top left: 3D projection with CEBRA, each sample colour-coded based on environment. Top right: 3D projection with CEBRA, each sample colour-coded based on cluster assignment from k-means. Bottom: As a function of time: position, running speed and prediction from the ensemble decoder obtained.

We employed the CEBRA method for latent embeddings, and built a binary decoder trained to predict which environment was being explored based solely on neuronal activity.

Alt: Illustration of the virtual-reality system. Top left: setup used, with a spherical mirror and a projector. Top right: a view from environment A, as well as the reward zone located at the end of the corridor. Bottom: Same for environment A’ (left) and B (right), with reward zone in the middle of the corridor.

During each session, either two very distinct environments were alternating at random (A-B) or two more similar corridors (A-A’). Animal received a reward when stopping long enough within an uncued location. This location was different in environment A and A’/B, forcing the animal to discriminate.

Alt: A panel illustrating the principle of active navigation, when position is derived from the running speed, and passive exposure, when position is decoupled from running speed.

We used 2-photon imaging to record mice navigating in virtual-reality.
🎮 During active navigation, their position along the track was controlled by the distance run on the wheel.
📺 In passive exposure, instead of converting speed into a position, we broadcasted a replay from another session.

Task engagement differentially drives hippocampal and neocortical neural codes Sensory inputs are progressively transformed into internal representations of the environment along the cortical hierarchy. How does the behavioral relevance of these inputs affect this encoding? Usin...

The main project from my PhD, in collaboration with Manuela Allegra and @schlab.bsky.social is now available as a preprint! We wondered how the hippocampus and the visual cortex may differ in the way they refine sensory inputs into internal representations

Well deserved! Congrats!

sleep workshop

🌍🧠 💤Join us on June 20th, 2025, in Oslo for a workshop that bridges System Neuroscience and Sleep Research in partnership with @esrs.bsky.social @ncmbm.bsky.social @sainsburywellcome.bsky.social @uio.no @KU
A satellite of the FENS regional meeting, register here:
frm2025oslo.no/basic-sleep-...

The scenes in the Oval Office today will shame the US for decades. They’ll never be forgotten.

A world leader, fighting for his country against the 21st century’s Nazis, came to the US and was attacked & abused by a gangster regime siding with the fascist invaders.

A historic disgrace.

I completely forgot to mention it here, but I actually defended my PhD last fall! And I recently started as a postdoctoral fellow in Oslo, in @charlotteboccara.bsky.social group. Back to the Scandinavian weather ☃️.

A Prefrontal Cortex Map based on Single Neuron Activity The intrinsic organization underlying the central cognitive role of the prefrontal cortex (PFC) is poorly understood. The work to date has been dominated by cytoarchitecture as a canvas for studies on...

Our new study is out on BioRXiv!

tinyurl.com/pfcmap

We (@carlenlab.bsky.social lab) mapped the mouse PFC using single-unit activity! We recorded ~23,000 neurons across cortical/subcortical regions and profiled spont. firing patterns to reveal what separates the PFC from other brain regions.

1/n

After a few days on Bluesky, I'm not sure what I miss most about Twitter. Weird Ai-generated ads? Sex bots offering nudes? The app not working while my phone is charging? The imbecile owner being praised as a genius? Anyway, hello everyone! I'll try to be slightly more active here, hopefully.

Having such a cute doggo to showcase feels like cheating!