Finally, big shout out to all the hard-working individuals who contributed to this project. Grateful for all your effort and rigor! And the Kheirbek lab in general…GREAT place to do science.

Yet, it’s undeniable that vhpc plays a prominent role in emotional processing. So, then, how does it contribute to inferring the meaning/value/valence of events? A work in progress.

The more we probe this region, the more it keeps telling us that it is recruited by salient, behaviorally relevant stimuli, with its neurons encoding “objective” properties of these stimuli, and not their subjective meaning.

But at the level of real-time stimulus responding, at least, our extensive search turned up next to nothing. And while we DID expect to find valence encoding going into this project, the results are actually quite consistent with our 2023 report….

Does this mean valence is def. not represented in vCA1? Not necessarily. Perhaps it’s just too weak to detect with the many methods & paradigms we threw at it. And others show co-expression of IEGs in vCA1 is greater for neurons exposed to stimuli of similar vs dissimilar valence.

All together then, we show that vCA1 neurons strongly encode stimulus identity, modality, and intensity. But, try as we might, we did not detect any appreciable valence encoding.

And they are…at first. But following repeated exposure and cue-outcome learning, low and high shock representations become highly distinct.

Well then, what about representations not of the cues, but of the low and high shock stimuli themselves (the USs)? Same qualitative stimulus, just different intensities. Surely those representations will be more similar to one another than, say, sucrose representations….

Ok then, vCA1 doesn’t encode the valence of unconditioned stimuli! .But perhaps valence info is present in conditioned stimuli? Two neutral odor cues that both predict negative outcomes (low or high shock), will those show greater similarity after cue-outcome learning? .Still no

Hmmmm! What if we take a stimulus and manipulate its valence from positive to negative (via conditioned taste aversion)? Will the representation come to more closely resemble that of a negative stimulus (of the same modality)? No!

Hmmm. Maybe we don’t see it because our stimuli have been from different sensory modalities. Maybe valence encoding will present itself if we only use stimuli of the same modality. Nope

That was unexpected. Alright then, we’ll do it again. Using different stimuli. And more stimuli…. Same result

Because the ventral hippocampus definitely encodes stimulus valence, right? Of course. So it began with a quick study to confirm this and move on….Only, we found no strong evidence in of support valence coding

but that paper primarily focused on how learning is encoded within vhpc, using few stimuli. Here, we used a wide range of stimuli to analyze what info vhpc is extracting and broadcasting. Valence encoding, recently reported in several limbic regions, seemed a good place to start.

For the past few years we’ve been pursuing a very simple question: what indeed does the vhpc care about? For this, we eavesdrop on cells to understand what info about the world they see fit to encode. Our previous paper gave us some interesting clues.

The vhpc is a central limbic hub, interfacing learning, cognition & emotion. It is believed to integrate external stimuli with internal drives, imparting meaning to these stimuli in the process; eg, encoding the + or - quality (valence) of stimuli to support adaptive behavior.

New preprint is up examining what information is encoded by the ventral hippocampus (vhpc).Gotta love those studies where your initial hypothesis is thoroughly destroyed by the data. This one reframed how I think about the vhpc. 🧵.

Hey #NeuroTwitter #SciTwitter:.Anyone know of a good IHC antibody for tdTomato?.Mouse brain sections. Not really concerned about mono/poly, what animal raised in, or cross-reaction with similar fluorophores (including GFP).

Great design, clean results, insightful conclusions. Nice.

RT @denisejcai: 📢 The Cai Lab is recruiting technicians! Neuroscience, computational, or psychology related experience is preferred. If yo….