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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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Development of Prefrontal Cortex: Regions of PFC

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Dr. Rishabh Pathak


The prefrontal cortex (PFC) is a critical brain region associated with higher-order cognitive functions, including executive function, decision-making, social behavior, and emotional regulation. The PFC undergoes significant development across the lifespan, with distinct regions contributing to various aspects of cognitive control and behavior. Here are the key regions of the prefrontal cortex and their functions:

1.     Orbitofrontal Cortex (BA 11):

o    Location: Located in the ventromedial part of the PFC.

o  Function: The orbitofrontal cortex is involved in decision-making, reward processing, emotional regulation, and social behavior. It plays a role in evaluating the emotional and motivational significance of stimuli and guiding adaptive behavior based on reward outcomes.

2.     Ventrolateral PFC (BA 44, 45, 47):

o    Location: Situated in the lower lateral aspects of the PFC.

o Function: The ventrolateral PFC is associated with cognitive control, working memory, language processing, and response inhibition. It plays a role in maintaining task-relevant information, manipulating information, and regulating attention during complex cognitive tasks.

3.     Dorsolateral PFC (BA 9, 46):

o    Location: Located in the upper lateral aspects of the PFC.

o   Function: The dorsolateral PFC is involved in executive functions such as planning, problem-solving, cognitive flexibility, and goal-directed behavior. It plays a crucial role in working memory, mental manipulation of information, and strategic decision-making.

4.     Rostrolateral PFC (BA 10):

o    Location: Situated in the rostral part of the lateral PFC.

o Function: The rostrolateral PFC is associated with cognitive control, attentional processes, and multitasking. It plays a role in monitoring and coordinating complex cognitive operations, integrating information from multiple sources, and maintaining task sets for goal-directed behavior.

These regions of the prefrontal cortex work in concert to support various aspects of executive function and cognitive control. The hierarchical organization of the PFC allows for the integration of information, the regulation of behavior, and the coordination of complex cognitive processes. Understanding the functions of different regions within the prefrontal cortex provides insights into the neural basis of higher cognitive functions and the role of the PFC in adaptive behavior and decision-making processes.

 

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