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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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Stability Vs Mobility

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Dr. Rishabh Pathak

Stability and mobility are two essential components of human movement that work together to support optimal performance, prevent injuries, and maintain functional abilities. Understanding the differences and relationship between stability and mobility is crucial in biomechanics and movement science. Here is a comparison of stability vs. mobility:

Stability:

1.    Definition:

o    Stability refers to the ability of a system, such as the human body or a joint, to maintain or return to a balanced and controlled position after being disturbed.

2.    Key Points:

o    Stability provides support, control, and resistance to external forces during movement.

o    It involves maintaining equilibrium, preventing falls, and resisting excessive motion or displacement.

o    Factors influencing stability include base of support, center of gravity, joint congruency, and neuromuscular control.

3.    Importance:

o  Stability is crucial for maintaining posture, balance, and joint integrity.

o  It plays a key role in injury prevention, efficient movement patterns, and functional performance.

4.    Training Focus:

o    Stability training focuses on improving neuromuscular control, core strength, and joint stability through exercises that challenge balance and proprioception.

Mobility:

1.    Definition:

o    Mobility refers to the ability of a joint or the body to move through a full range of motion efficiently and effectively.

2.    Key Points:

o    Mobility involves flexibility, muscle length, and joint range of motion.

o   It allows for smooth and unrestricted movement patterns, enhancing functional activities and sports performance.

3.    Importance:

o    Mobility is essential for performing daily tasks, sports-specific movements, and exercises with proper technique and reduced risk of injury.

o    It supports joint health, movement efficiency, and overall functional abilities.

4.    Training Focus:

o    Mobility training focuses on improving joint range of motion, muscle flexibility, and movement quality through stretching, mobility drills, and corrective exercises.

Relationship between Stability and Mobility:

  • Balance: Optimal movement patterns require a balance between stability and mobility at each joint. While stability provides support and control, mobility allows for fluid and unrestricted movement.
  • Integration: Stability and mobility are interconnected concepts in biomechanics. Improving stability can enhance mobility by providing a solid foundation for movement, while enhancing mobility can support stability by allowing for proper joint function.

Conclusion:

Stability and mobility are complementary aspects of human movement that work together to ensure efficient, safe, and effective performance. By addressing both stability and mobility through targeted training, individuals can optimize movement quality, prevent injuries, and enhance overall functional abilities in various activities and sports.

 

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