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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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Explain the functions of the anterior cingulate cortex and lateral prefrontal cortex in relation to brain development?

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Dr. Rishabh Pathak

The anterior cingulate cortex (ACC) and lateral prefrontal cortex (LPFC) are two key regions of the brain that play critical roles in various cognitive functions and are integral to brain development. Here is an overview of their functions in relation to brain development:


1.     Anterior Cingulate Cortex (ACC):

o    Emotional Regulation: The ACC is involved in emotional regulation and processing. It plays a role in monitoring emotional responses, detecting errors, and regulating emotional reactions to stimuli.

o    Cognitive Control: The ACC is crucial for cognitive control processes such as attention, decision-making, conflict monitoring, and response inhibition. It helps in coordinating cognitive functions and adjusting behavior based on task demands.

o    Social Cognition: The ACC is implicated in social cognition, empathy, and theory of mind. It contributes to understanding others' emotions, intentions, and mental states.

o    Brain Development: The ACC undergoes developmental changes across the lifespan, with significant maturation during adolescence and into adulthood. Its structural and functional development is linked to improvements in cognitive control and emotional regulation.

2.     Lateral Prefrontal Cortex (LPFC):

o    Executive Functions: The LPFC is associated with higher-order cognitive functions known as executive functions. These include working memory, cognitive flexibility, planning, decision-making, and goal-directed behavior.

o    Inhibition and Control: The LPFC plays a crucial role in inhibitory control, allowing individuals to suppress irrelevant information, resist impulses, and focus on task-relevant stimuli. It is essential for self-regulation and goal-directed behavior.

o    Working Memory: The LPFC is involved in working memory processes, which enable the temporary storage and manipulation of information for cognitive tasks. It supports the maintenance and updating of information in the mind.

o    Brain Development: The LPFC undergoes protracted development, with structural and functional changes occurring throughout childhood, adolescence, and into adulthood. Maturation of the LPFC is associated with improvements in executive functions and cognitive control.

Both the ACC and LPFC are critical for cognitive, emotional, and social functioning, and their development is closely linked to the maturation of higher-order cognitive processes. Understanding the roles of these brain regions in brain development provides insights into how cognitive abilities evolve across different stages of life.

 

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