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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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Neural Pattering in the Embryonic Period

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Dr. Rishabh Pathak


Neural patterning in the embryonic period is a complex process that involves the establishment of regional identities and the differentiation of neural progenitor cells into specific cell types. Here are key points regarding neural patterning in the embryonic period:


1.     Regional Specification:

o    During the embryonic period, regional specification of the neural tube occurs, leading to the formation of distinct brain regions with unique identities.

o    The neural tube gives rise to the forebrain (prosencephalon), midbrain (mesencephalon), and hindbrain (rhombencephalon), which further differentiate into specific structures within each region.

o    Graded patterns of molecular signaling in the neocortical proliferative zone contribute to the regional elaboration of the brain, establishing primitive patterning of sensorimotor regions by the end of the embryonic period.

2.     Genetic Patterning:

o    Genetic signaling pathways play a crucial role in neural patterning during the embryonic period, guiding the differentiation of neural progenitor cells and the formation of distinct brain regions.

o    Interactions between genetic factors and environmental cues influence the regional specification of the developing brain, shaping the overall organization and function of neural circuits.

o    The establishment of regional identities within the embryonic brain sets the stage for later developmental processes and the refinement of neural connections in specific brain regions.

3.     Neurogenesis and Differentiation:

o    Neurogenesis, the process of generating neurons from neural progenitor cells, is tightly regulated during the embryonic period to ensure the proper formation of neural structures.

o    Differentiation of neural progenitor cells into specific cell types is guided by molecular cues and genetic patterning, leading to the development of diverse neuronal populations within the embryonic brain.

o    The differentiation of neural progenitor cells into region-specific cell types contributes to the establishment of functional brain areas and the early organization of neural circuits critical for brain function.

In summary, neural patterning in the embryonic period involves the regional specification of the developing brain, guided by genetic signaling pathways and molecular interactions. This process sets the foundation for the differentiation of neural progenitor cells, neurogenesis, and the establishment of distinct brain regions essential for the maturation and functionality of the central nervous system.

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