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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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NCAM - A Common Regulator of Growth Factors in Brain

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Dr. Rishabh Pathak

Neural Cell Adhesion Molecule (NCAM) is known to interact with and modulate the activity of various growth factors in the brain. Here are some key points highlighting NCAM's role as a common regulator of growth factors in the brain:


1.      Interaction with Growth Factors:

o   NCAM interacts with a variety of growth factors, including but not limited to nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), fibroblast growth factor (FGF), and insulin-like growth factor (IGF).

o    These interactions can occur through direct binding between NCAM and growth factors or through indirect mechanisms involving signaling pathways and downstream effectors.

2.     Modulation of Signaling Pathways:

o  NCAM can modulate the signaling pathways activated by growth factors, influencing processes such as cell survival, proliferation, differentiation, and synaptic plasticity.

o    By interacting with growth factor receptors or downstream signaling molecules, NCAM can regulate the intensity and duration of growth factor signaling in neural cells.

3.     Neurotrophic Effects:

o    NCAM's interactions with growth factors contribute to neurotrophic effects in the brain, promoting neuronal survival, neurite outgrowth, synaptogenesis, and synaptic connectivity.

o    Through its ability to enhance the effects of growth factors, NCAM plays a crucial role in supporting the development, maintenance, and plasticity of the nervous system.

4.    Regulation of Neurogenesis:

o NCAM's involvement in regulating growth factors is linked to processes of neurogenesis, including the proliferation, migration, and differentiation of neural stem cells into mature neurons.

o    By coordinating the actions of growth factors, NCAM contributes to the generation of new neurons and the formation of functional neural circuits in the developing and adult brain.

5.     Implications for Brain Function:

o    The coordinated regulation of growth factors by NCAM is essential for normal brain function, including learning, memory, cognitive processes, and adaptive responses to environmental stimuli.

o    Dysregulation of NCAM-mediated growth factor signaling can impact neuronal development, synaptic plasticity, and the pathophysiology of neurological disorders.

In summary, NCAM serves as a common regulator of growth factors in the brain by interacting with and modulating the activity of various growth factors involved in neurotrophic effects, signaling pathways, neurogenesis, and brain function. This multifaceted role of NCAM highlights its significance in orchestrating growth factor-mediated processes critical for neural development, plasticity, and function in the central nervous system.

 

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