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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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Distal Segments

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Dr. Rishabh Pathak

In biomechanics, distal segments refer to the anatomical regions or structures that are located further away from the center of the body or further away from the point of attachment to the trunk. These distal segments play a crucial role in fine motor control, precision movements, and endpoint coordination during various activities. Understanding the characteristics and functions of distal segments is essential for analyzing biomechanical interactions, joint mechanics, and muscle actions in human movement. Key points related to distal segments in biomechanics include:


1.     Distal Muscles: Distal muscles are those located further away from the trunk or core of the body and often contribute to movements involving fine motor control, dexterity, and precision. Examples of distal muscles include the intrinsic hand muscles, which are responsible for finger movements and grip strength, and the tibialis anterior, which controls dorsiflexion of the foot during activities like walking and running.


2.     Distal Joint Mobility: Distal segments, such as the wrist and ankle joints, are essential for providing mobility and flexibility in movements that require intricate coordination and endpoint control. Structures like the wrist ligaments and the ankle joint articulations allow for precise movements, adjustments, and adaptations in tasks that involve manipulation, grasping, and foot placement.


3.     Distal Endpoint Coordination: Distal segments play a key role in coordinating endpoint movements and fine adjustments during tasks that require accuracy and precision. Structures like the hand digits and the foot arches contribute to endpoint control, tactile feedback, and sensory integration, enabling individuals to perform tasks that involve manipulation, tool use, and balance maintenance.


4.     Distal Force Application: Distal segments are responsible for applying forces and pressures to external objects or surfaces, allowing for interaction with the environment and object manipulation. The distal segments, including the hands and feet, act as contact points for force transmission, grip strength, and tactile feedback, facilitating tasks like grasping, pushing, and balancing.


5.     Distal Kinematics: Distal segments influence the kinematics of proximal joints and body segments by providing feedback and control during movement execution. Analyzing the kinematics of distal segments, such as the hand and foot, helps researchers understand how endpoint movements affect overall limb motion, joint angles, and task performance in activities that require precision and coordination.


6.     Distal Sensory Integration: Distal segments are rich in sensory receptors and feedback mechanisms that contribute to proprioception, touch sensitivity, and spatial awareness during movement execution. Sensory integration from distal segments informs motor control, grip force modulation, and endpoint accuracy in tasks that involve object manipulation, tool use, and fine motor skills.

By examining the characteristics and functions of distal segments in biomechanics, researchers can gain insights into the role of distal structures in movement precision, endpoint control, and sensory-motor integration. Analyzing the biomechanical properties of distal muscles, joints, and sensory feedback mechanisms contributes to a comprehensive understanding of movement mechanics, skill acquisition, and performance optimization strategies in sports, rehabilitation, and occupational tasks that require fine motor control and endpoint coordination.

 

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