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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 genetic patterning and neurogenesis play a role in brain maturation?

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Dr. Rishabh Pathak

Genetic patterning and neurogenesis are fundamental processes that play crucial roles in brain maturation, as outlined in the PDF file on brain development.


1.     Genetic Patterning: Genetic patterning refers to the intricate process by which genes regulate the development of the brain. Genes play a significant role in orchestrating the formation of various brain structures and functions. During the embryonic period, genetic signaling is essential for initiating and guiding the development of the brain. Specific genes are expressed in different populations of cells, generating molecular signals that influence the developmental trajectory of other cell populations. This genetic interplay is vital for establishing the initial framework of the brain's structure and function.


2.     Neurogenesis: Neurogenesis is the process by which new neurons are generated from neural stem cells and progenitor cells. This process is particularly active during prenatal and early postnatal periods, contributing to the expansion of the brain's neuronal population. The document highlights that structural changes in both gray and white matter compartments continue through childhood and adolescence, paralleling changes in functional organization and behavior.


During early brain development, neurogenesis is essential for the formation of neural circuits and the establishment of neuronal connections. The exuberant connectivity observed in the developing brain is a result of neurogenesis, creating a foundation for subsequent pruning and refinement of neural networks based on experience. Additionally, genetic interplay between transcription factors, such as Sp8 and Emx2, influences the patterning of the forebrain, further shaping the developing brain.


In conclusion, genetic patterning and neurogenesis are integral processes in brain maturation. Genetic factors guide the initial development of the brain, while neurogenesis contributes to the generation of neurons and the establishment of neural circuits critical for brain function. These processes work in concert to shape the complex and dynamic maturation of the brain throughout development.

 

Stiles, J. (2008). The fundamentals of brain development: Integrating nature and nurture. Cambridge, MA: Harvard University Press.

 

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