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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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Finite Growth Theory

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Dr. Rishabh Pathak

Finite growth theory is a mathematical framework used to describe the growth and deformation of biological tissues over time. In the context of brain development and cortical folding, finite growth theory plays a crucial role in understanding how the brain tissue evolves and changes shape during development. Here are key points related to finite growth theory:


1. Definition: Finite growth theory considers biological tissues as deformable continua that undergo growth and remodeling processes. It accounts for changes in tissue shape, size, and structure over time due to cellular activities such as proliferation, differentiation, and migration.


2. Continuum Mechanics: Finite growth theory is often formulated within the framework of continuum mechanics, which describes the behavior of continuous media subject to external forces and deformations. By applying principles of continuum mechanics, researchers can model the growth and deformation of tissues at different length scales.


3.  Growth Kinematics: In finite growth theory, growth kinematics describe how tissue elements deform and change size as a result of growth processes. This includes defining how growth rates vary spatially and temporally within the tissue, influencing its overall morphology.


4.   Material Growth: The concept of material growth in finite growth theory refers to the changes in tissue properties such as stiffness, density, and composition as the tissue grows. Material growth is essential for capturing the evolving mechanical behavior of tissues undergoing growth and remodeling.


5.  Growth Laws: Finite growth theory often incorporates growth laws that govern how tissue properties evolve in response to growth stimuli. These growth laws can be based on experimental observations or biological principles, providing a mathematical framework for simulating tissue growth and deformation.


6.   Computational Modeling: Finite growth theory is frequently implemented using computational models, such as finite element analysis, to simulate the growth and deformation of tissues. Computational simulations allow researchers to predict how tissues will deform under different growth conditions and study the underlying mechanisms driving tissue morphogenesis.


7.  Biological Applications: In the context of brain development, finite growth theory helps researchers understand the mechanisms underlying cortical folding, gyrification, and brain morphogenesis. By incorporating growth dynamics into mathematical models, researchers can simulate the complex processes that shape the structure of the developing brain.


In summary, finite growth theory provides a mathematical framework for studying the growth and deformation of biological tissues, including the brain, and plays a key role in elucidating the mechanisms driving tissue morphogenesis during development.

 

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