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Unveiling Hidden Neural Codes: SIMPL – A Scalable and Fast Approach for Optimizing Latent Variables and Tuning Curves in Neural Population Data

Dr. Rishabh Pathak
This research paper presents SIMPL (Scalable Iterative Maximization of Population-coded Latents), a novel, computationally efficient algorithm designed to refine the estimation of latent variables and tuning curves from neural population activity. Latent variables in neural data represent essential low-dimensional quantities encoding behavioral or cognitive states, which neuroscientists seek to identify to understand brain computations better. Background and Motivation Traditional approaches commonly assume the observed behavioral variable as the latent neural code. However, this assumption can lead to inaccuracies because neural activity sometimes encodes internal cognitive states differing subtly from observable behavior (e.g., anticipation, mental simulation). Existing latent variable models face challenges such as high computational cost, poor scalability to large datasets, limited expressiveness of tuning models, or difficulties interpreting complex neural network-based functio...
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How do pharmacological interventions targeting NMDA glutamate receptors and PKCc affect alcohol drinking behavior in mice?

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Dr. Rishabh Pathak

Pharmacological interventions targeting NMDA glutamate receptors and PKCc can have significant effects on alcohol drinking behavior in mice. In the context of the study discussed in the PDF file, the researchers investigated the impact of these interventions on ethanol-preferring behavior in mice lacking type 1 equilibrative nucleoside transporter (ENT1).


1.  NMDA Glutamate Receptor Inhibition: Inhibition of NMDA glutamate receptors can reduce ethanol drinking behavior in mice. This suggests that NMDA receptor-mediated signaling plays a role in regulating alcohol consumption. By blocking NMDA receptors, the researchers were able to observe a decrease in ethanol intake in ENT1 null mice, indicating that NMDA receptor activity is involved in the modulation of alcohol preference.


2.  PKCc Inhibition: Down-regulation of intracellular PKCc-neurogranin (Ng)-Ca2+-calmodulin dependent protein kinase type II (CaMKII) signaling through PKCc inhibition is correlated with reduced CREB activity in ENT1 null mice. CREB activity is associated with the regulation of gene expression related to neuronal plasticity and behavior. In this context, reduced CREB activity may impact the neural mechanisms underlying alcohol drinking behavior.


Overall, these findings suggest that the genetic deletion or pharmacological inhibition of ENT1 can modulate NMDA glutamate receptor-mediated signaling pathways, leading to alterations in CREB activity and ultimately influencing ethanol-preferring behavior in mice. This highlights the intricate interplay between glutamatergic signaling, PKCc activity, and alcohol consumption behavior in the context of ENT1 deficiency.

 

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