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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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Quantitative Problems in Biomechanics

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Dr. Rishabh Pathak


Quantitative problems in biomechanics involve the application of mathematical and computational  methods to analyze and quantify the mechanical aspects of human movement. These quantitative approaches provide numerical data and measurements to assess forces, torques, velocities, accelerations, and other biomechanical parameters. Some common quantitative problems in biomechanics include:

1.    Force Analysis: Quantitatively measuring and analyzing forces acting on the human body during movement, such as ground reaction forces, muscle forces, joint reaction forces, and external loads. Force platforms, pressure sensors, and electromyography (EMG) are used to quantify forces and moments in various activities.

2.     Kinematic Analysis: Quantitatively assessing the motion and position of body segments, joints, and limbs using motion capture systems, inertial sensors, and imaging techniques. Kinematic data provide information on joint angles, angular velocities, linear displacements, and movement trajectories.

3.     Kinetic Analysis: Quantitatively studying the forces and torques that cause or result from motion, including joint moments, muscle forces, and segmental interactions. Kinetic analysis helps understand the internal and external forces involved in movement and their impact on performance and injury risk.

4.     Energy Analysis: Quantitatively evaluating energy expenditure, work done, and power generation during physical activities using metabolic measurements, energy calculations, and mechanical work analyses. Energy analysis provides insights into the efficiency and metabolic demands of movement.

5.  Biomechanical Modeling: Quantitatively developing mathematical models and simulations to predict and analyze human movement mechanics, muscle activations, joint forces, and performance outcomes. Computational modeling allows for virtual testing of hypotheses, optimization of movement strategies, and design of interventions.

6.  Gait Analysis: Quantitatively assessing walking and running patterns through spatiotemporal parameters, kinematics, kinetics, and muscle activations. Gait analysis helps diagnose gait abnormalities, monitor rehabilitation progress, and optimize orthotic interventions.

7.     Sports Performance Analysis: Quantitatively evaluating sports techniques, athletic movements, and performance metrics to enhance training programs, optimize skill development, and improve competitive outcomes. Performance analysis in sports biomechanics involves quantifying key performance indicators and identifying areas for improvement.

8.     Injury Biomechanics: Quantitatively investigating the biomechanical mechanisms of injuries, such as impact forces, tissue loading, and injury risk factors. Biomechanical analyses of injury mechanisms help design injury prevention strategies, protective equipment, and rehabilitation protocols.

9. Rehabilitation Biomechanics: Quantitatively assessing movement impairments, functional limitations, and treatment outcomes in rehabilitation settings. Biomechanical evaluations guide the development of personalized rehabilitation plans, monitor progress, and optimize recovery strategies.



By addressing these quantitative problems in biomechanics, researchers, clinicians, coaches, and practitioners can obtain objective data, quantify biomechanical parameters, analyze movement mechanics, and make evidence-based decisions to enhance performance, prevent injuries, optimize rehabilitation, and improve overall understanding of human movement. Quantitative biomechanical analyses play a crucial role in advancing research, sports science, clinical practice, and biomechanical engineering.

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