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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, environmental, biochemical, and physical events interact to influence neurodevelopment?

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Dr. Rishabh Pathak

Genetic, environmental, biochemical, and physical events interact in a complex manner to influence neurodevelopment. Here is an explanation of how each of these factors plays a role:


1.     Genetic Factors: Genetic factors provide the blueprint for neurodevelopment by determining the initial structure and function of the brain. Genes regulate processes such as neuronal differentiation, migration, and connectivity, which are essential for the formation of neural circuits. Variations in genes can impact the development of the brain and contribute to neurodevelopmental disorders.


2.     Environmental Factors: Environmental factors, including prenatal and postnatal experiences, exposure to toxins, nutrition, and social interactions, can significantly influence neurodevelopment. Environmental stimuli can shape neuronal connections, synaptic plasticity, and brain structure. Adverse environmental conditions, such as stress or malnutrition, can disrupt normal neurodevelopment and lead to cognitive and behavioral impairments.


3.     Biochemical Factors: Biochemical processes, such as neurotransmitter signaling, neurotrophic factors, and gene expression, play a crucial role in neurodevelopment. These factors regulate neuronal growth, survival, and synaptic plasticity. Imbalances in biochemical signaling pathways can disrupt normal brain development and contribute to neurological disorders.


4. Physical Factors: Physical forces, such as mechanical stress, tension, and differential growth, also impact neurodevelopment. These forces influence the folding of the cerebral cortex, a critical process in brain development. Mechanical forces generated by neuronal migration, axon guidance, and synaptogenesis contribute to the formation of neural circuits and the overall structure of the brain.


Overall, the interaction of genetic, environmental, biochemical, and physical factors is essential for the intricate process of neurodevelopment. Understanding how these factors influence brain development can provide insights into normal brain function and the pathogenesis of neurological disorders.

 

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