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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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What are the different perspectives on how functional specialization of regions of the cerebral cortex arises in the human brain?

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Dr. Rishabh Pathak

The different perspectives on how functional specialization of regions of the cerebral cortex arises in the human brain are: 

1.     Intrinsic Genetic and Molecular Mechanisms Perspective:

  • One perspective posits that the functional specialization of regions of the cerebral cortex arises primarily through intrinsic genetic and molecular mechanisms.
  • According to this view, genetic factors play a significant role in determining the initial organization and specialization of different brain regions.
  • Experience is considered to have a role in fine-tuning the functional properties of these specialized regions rather than being the primary driver of their development.

2.     Experience-Dependent Specialization Perspective:

  • An alternative perspective suggests that some aspects of human functional brain development involve a prolonged process of specialization that is shaped by postnatal experience.
  • This view emphasizes the influence of environmental stimuli and experiences in sculpting the functional organization of the cerebral cortex.
  • It proposes that the interactions between the developing brain and the external environment play a crucial role in determining how specific regions of the cortex become specialized for different functions.

3.     Interaction Between Genetic Factors and Postnatal Experience Perspective:

  • A more integrated perspective acknowledges the interplay between intrinsic genetic factors and postnatal experiences in shaping the functional specialization of cortical regions.
  • This viewpoint suggests that while genetic predispositions establish a foundation for brain development, experiences during infancy and childhood contribute to the refinement and adaptation of neural circuits.
  • It highlights the dynamic and interactive nature of brain development, where genetic predispositions and environmental influences work together to shape the functional organization of the cerebral cortex.

Overall,  a nuanced understanding of how the functional specialization of regions of the cerebral cortex arises in the human brain, considering the complex interplay between genetic factors, postnatal experiences, and environmental influences. These perspectives underscore the intricate processes involved in the development of specialized brain functions and highlight the importance of both intrinsic and extrinsic factors in shaping the functional organization of the human cortex.

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