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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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General Principles of Plasticity and Behavior in the Development of Brain

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Dr. Rishabh Pathak

"Brain Plasticity and Behaviour in the Developing Brain" discusses general principles of plasticity and behavior in brain development. Here are some key points regarding this topic:


1.     Complex Interplay of Genetic and Experiential Factors: Brain development is not solely determined by genetic factors but also involves a complex interaction with environmental experiences. This interplay shapes the emerging brain and influences its development and function.


2.     Brain Development Progresses Through Stages: Brain development involves a series of stages, including neurogenesis, cell migration, maturation, synaptogenesis, synaptic pruning, and myelination. Each stage plays a crucial role in shaping the structure and function of the brain.


3.     Dendritic and Axonal Growth: The formation of dendrites and axons is essential for establishing neural connections and synaptic networks in the brain. Dendritic growth is slower than axonal growth, but both processes are crucial for proper brain development.


4.     Synapse Formation and Pruning: The brain forms a vast number of synapses, guided by environmental cues and signals. Synaptic pruning eliminates unnecessary connections, refining neural circuits and optimizing brain function. The manipulation of environmental cues can lead to significant changes in cerebral circuitry.


5.     Plasticity Throughout Life: Plastic changes in the brain support improved motor and cognitive functions. However, not all plasticity is beneficial, and maladaptive changes can occur in response to factors like psychoactive drugs, stress, and pathological conditions.


6. Impact of Environmental Events: Environmental factors such as sensory stimuli, psychoactive drugs, and parental-child relationships can influence brain development and function. Positive experiences can promote healthy brain development, while adverse events can lead to detrimental effects on the brain.


Understanding the general principles of plasticity and behavior in brain development provides insights into the dynamic processes that shape the developing brain. The intricate interplay between genetic predispositions and environmental influences highlights the complexity of brain plasticity and its impact on behavior throughout the lifespan.

 

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