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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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Progressive Supranuclear Palsy (PSP)

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Dr. Rishabh Pathak

Progressive Supranuclear Palsy (PSP) is a rare neurodegenerative disorder that affects movement, balance, vision, speech, and cognition. Here is an overview of Progressive Supranuclear Palsy:


1.      Clinical Features:

oPSP is characterized by the progressive deterioration of brain cells in certain areas of the brain, leading to motor and cognitive impairments.

oCommon symptoms include difficulties with balance and walking (resulting in frequent falls), stiffness and slowness of movement, changes in eye movements (such as difficulty looking up and down), speech difficulties, and cognitive impairment.

oPSP is often misdiagnosed initially as Parkinson's disease due to overlapping symptoms, but it has distinct features such as early postural instability and vertical gaze palsy.

2.     Pathology:

oThe hallmark pathological feature of PSP is the accumulation of abnormal tau protein in nerve cells in specific brain regions, leading to cell dysfunction and death.

oThe affected brain areas in PSP include the basal ganglia, brainstem, and regions of the cerebral cortex involved in motor control and cognition.

3.     Diagnosis:

oDiagnosis of PSP is challenging and often requires a comprehensive evaluation by a neurologist specializing in movement disorders.

oClinical criteria, neuroimaging studies (such as MRI), and sometimes cerebrospinal fluid analysis may be used to support the diagnosis.

4.    Treatment:

oThere is no cure for PSP, and treatment focuses on managing symptoms and improving quality of life.

oMedications may be prescribed to address specific symptoms such as movement difficulties, depression, and sleep disturbances.

oPhysical therapy, occupational therapy, speech therapy, and assistive devices can help maintain function and independence.

5.     Research and Future Directions:

oOngoing research aims to better understand the underlying mechanisms of PSP, develop biomarkers for early diagnosis, and explore potential disease-modifying treatments.

oClinical trials investigating novel therapies, including tau-targeting drugs and symptomatic treatments, are underway to address the unmet medical needs of PSP patients.

In summary, Progressive Supranuclear Palsy (PSP) is a complex neurodegenerative disorder characterized by motor impairments, cognitive changes, and visual disturbances. While there is currently no cure for PSP, ongoing research offers hope for improved diagnostic tools and therapeutic interventions to enhance the quality of life for individuals affected by this condition.

 

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