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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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Translation Dysregulation in Autism Spectrum Disorders

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Dr. Rishabh Pathak

Translation dysregulation, a phenomenon characterized by abnormalities in protein synthesis processes, has been implicated in Autism Spectrum Disorders (ASD) and may contribute to the pathophysiology of the condition. Here is an overview of translation dysregulation in ASD:


1.      Dysregulation of Protein Synthesis:

o   mTOR Signaling Pathway: Dysregulation of the mammalian target of rapamycin (mTOR) signaling pathway, a key regulator of protein synthesis, has been observed in individuals with ASD. Abnormal activation of mTOR can lead to excessive protein synthesis, altered synaptic plasticity, and disrupted neuronal connectivity in the brain [T19].

o Fragile X Syndrome: Fragile X syndrome, a genetic disorder associated with intellectual disability and ASD features, is characterized by dysregulation of protein synthesis due to mutations in the FMR1 gene. The absence of the FMRP protein leads to aberrant translation of synaptic proteins, contributing to cognitive impairments and behavioral symptoms in individuals with Fragile X syndrome and ASD [T20].

o RNA Binding Proteins: Dysfunctions in RNA binding proteins, such as FMRP, TSC2, and CYFIP1, have been linked to translation dysregulation in ASD. These proteins play crucial roles in regulating mRNA translation, synaptic protein synthesis, and neuronal function, and their dysregulation can disrupt protein homeostasis in individuals with ASD [T21].

2.     Impact on Synaptic Function:

o Synaptic Protein Expression: Abnormalities in translation regulation can affect the expression of synaptic proteins critical for synaptic transmission, plasticity, and connectivity. Dysregulated protein synthesis at synapses can lead to altered synaptic function, impaired neural circuitry, and cognitive deficits in individuals with ASD [T22].

o Long-Term Synaptic Plasticity: Dysregulation of translation processes can impact long-term synaptic plasticity mechanisms, such as long-term potentiation (LTP) and long-term depression (LTD), which are essential for learning and memory. Altered protein synthesis at synapses may disrupt synaptic plasticity and neural network formation in individuals with ASD [T23].

3.     Therapeutic Strategies:

o mTOR Inhibitors: Targeting the mTOR signaling pathway with mTOR inhibitors, such as rapamycin, has been proposed as a potential therapeutic strategy to modulate protein synthesis and restore synaptic homeostasis in individuals with ASD. By regulating mTOR activity, these inhibitors may help normalize translation dysregulation and improve neuronal function [T24].

oRNA-Based Therapies: Approaches aimed at correcting RNA dysregulation and restoring normal mRNA translation, such as RNA-targeted therapies and RNA editing technologies, hold promise for addressing translation abnormalities in ASD. By targeting specific RNA molecules involved in protein synthesis, these therapies may mitigate synaptic dysfunction and cognitive deficits in individuals with ASD [T25].

In summary, translation dysregulation in Autism Spectrum Disorders can disrupt protein synthesis processes, impact synaptic function, and contribute to the neurobiological underpinnings of the condition. Understanding the molecular mechanisms underlying translation abnormalities in ASD is essential for developing targeted interventions that can restore protein homeostasis, normalize synaptic function, and improve cognitive outcomes in individuals affected by ASD.

 

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