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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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Sensitive of surface morphology with respect to Growth Ratio

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Dr. Rishabh Pathak

The sensitivity of surface morphology with respect to the growth ratio between the cortex and subcortex is a critical aspect in understanding the mechanisms of cortical folding and brain development. Here are some key points regarding the sensitivity of surface morphology to the growth ratio:


1.     Secondary Folds Formation: The growth ratio between the cortex and subcortex is a key parameter controlling the formation of secondary folds in the cerebral cortex. Variations in the growth ratio can lead to changes in the complexity and distribution of cortical folds, influencing the overall surface morphology of the brain.


2.     Impact on Folding Patterns: The growth ratio influences the rate and extent of cortical growth, which in turn affects the folding patterns of the cortex. Variations in the growth ratio can result in alterations in the depth, frequency, and orientation of cortical folds, shaping the overall morphology of the brain surface.


3. Mechanotransduction Pathways: The growth ratio between the cortex and subcortex is linked to Mechanotransduction pathways that regulate cellular responses to mechanical stimuli. Changes in the growth ratio can modulate these pathways, leading to alterations in cell growth, proliferation, and tissue remodeling, which impact cortical folding patterns.


4.     Computational Modeling: Computational models can simulate the sensitivity of surface morphology to variations in the growth ratio by adjusting this parameter and observing the resulting changes in cortical folding patterns. These models provide insights into how the growth ratio influences the morphological features and structural organization of the cerebral cortex.


5.   Cellular Mechanisms: The growth ratio is closely tied to cellular mechanisms such as axon elongation, cell proliferation, and tissue growth, which collectively contribute to cortical development and folding. Understanding the interplay between the growth ratio and cellular processes is essential for unraveling the complexities of brain morphogenesis.


6.     Clinical Implications: Abnormalities in the growth ratio between cortical layers have been implicated in various neurodevelopmental disorders and brain pathologies. Investigating the sensitivity of surface morphology to the growth ratio can provide valuable insights into the underlying mechanisms of these conditions and potential therapeutic targets.


7.  Biological Significance: The growth ratio is a fundamental parameter that governs the dynamic changes in brain structure during development. It reflects the intricate balance between cortical and subcortical growth processes and their impact on cortical folding, highlighting the biological significance of the growth ratio in shaping brain morphology.


By exploring the sensitivity of surface morphology to the growth ratio, researchers can enhance their understanding of the mechanical and biological factors that drive cortical folding and brain development. This knowledge is essential for deciphering the complex interplay between growth processes, cellular mechanisms, and structural changes in the developing brain.

 

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