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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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Brain Development in the embryonic and early fetal periods

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Dr. Rishabh Pathak

During the embryonic and early fetal periods, significant developmental processes shape the formation of the human brain. Here are some key points regarding brain development during these stages:


1.     Embryonic Period:

o    The embryonic period extends through the eighth week post-conception (gestational week eight, or GW8) in humans.

o    By the end of the embryonic period, rudimentary structures of the brain and central nervous system are established, defining major compartments of the central and peripheral nervous systems.

o    Interactions between genetic signaling and environmental factors are crucial during this period, influencing the development of the embryonic brain.

o    Genetic patterning and neurogenesis play essential roles in guiding the initial stages of brain development, setting the foundation for subsequent growth and maturation.

2.     Early Fetal Period:

o    The early fetal period, extending to approximately midgestation, is critical for neocortical development.

o    Most cortical neurons are generated during this period, migrating to their positions in the neocortex and forming essential brain networks for information processing.

o    Rapid growth and elaboration of both cortical and subcortical structures occur during the fetal period, including the development of major fiber pathways.

o    Experience-dependent processes during the early postnatal period shape connectivity and neural competition, influencing the organization and function of the developing brain.

In summary, the embryonic and early fetal periods are foundational stages in brain development, marked by the establishment of basic brain structures, genetic influences, neurogenesis, and the beginning of essential brain networks. These early stages set the stage for further maturation and refinement of the intricate neural architecture that underlies human brain function.

 

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