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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 the Neural network circuits works in Parkinson's Disease?

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Dr. Rishabh Pathak

 


In Parkinson's disease, the neural network circuits involved in motor control are disrupted, leading to characteristic motor symptoms such as tremor, bradykinesia, and rigidity. The primary brain regions affected in Parkinson's disease include the basal ganglia and the cortex. Here is an overview of how neural network circuits work in Parkinson's disease:

1.     Basal Ganglia Dysfunction: The basal ganglia are a group of subcortical nuclei involved in motor control. In Parkinson's disease, there is a loss of dopamine-producing neurons in the substantia nigra, leading to decreased dopamine levels in the basal ganglia. This dopamine depletion results in abnormal signaling within the basal ganglia circuitry, leading to motor symptoms.

2.     Cortical Involvement: The cortex, particularly the motor cortex, plays a crucial role in initiating and coordinating voluntary movements. In Parkinson's disease, abnormal activity in the cortex, especially in the beta and gamma frequency bands, is observed and is associated with motor symptoms.

3.     Disrupted Neural Circuits: The communication between the basal ganglia, cortex, and other brain regions is disrupted in Parkinson's disease. This disruption leads to difficulties in initiating and controlling movements, resulting in the characteristic motor symptoms of the disease.

4.     Deep Brain Stimulation (DBS): Deep brain stimulation is a therapeutic approach that involves the implantation of electrodes in specific brain regions, such as the subthalamic nucleus (STN) or globus pallidus, to modulate neural activity and alleviate motor symptoms in Parkinson's disease. DBS works by delivering electrical impulses to targeted brain regions to normalize neural activity and improve motor function.

5.     Research Advances: Recent research has focused on decoding neural activity patterns associated with specific motor symptoms in Parkinson's disease. By understanding the neurophysiological fingerprints of tremor and bradykinesia, researchers aim to develop more targeted and personalized treatment strategies, such as closed-loop DBS paradigms that can adapt stimulation parameters based on real-time neural signals.

By studying the neural network circuits involved in Parkinson's disease and developing innovative treatment approaches, researchers aim to improve the management of motor symptoms and enhance the quality of life for individuals living with Parkinson's disease.

 

Lauro, P. M., Lee, S., Amaya, D. E., Liu, D. D., Akbar, U., & Asaad, W. F. (2023). Concurrent decoding of distinct neurophysiological fingerprints of tremor and bradykinesia in Parkinson’s disease. eLife, 12, e84135. https://doi.org/10.7554/eLife.84135

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