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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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De Constructing Smell

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Dr. Rishabh Pathak

Deconstructing smell involves understanding the complex process by which our olfactory system detects and interprets different odors. Here is a breakdown of the key components involved in the sense of smell:


1.    Odorants: Smell begins with the detection of odorants, which are volatile chemical compounds that emanate from substances in the environment. These odorants can be derived from a wide range of sources, such as food, flowers, or chemicals.


2. Olfactory Receptors: Olfactory receptors are specialized proteins located in the olfactory epithelium of the nasal cavity. These receptors are sensitive to specific odorant molecules and can detect a diverse array of smells. When an odorant binds to its corresponding olfactory receptor, it initiates a series of biochemical signals.


3.  Olfactory Bulb: The olfactory receptors send signals to the olfactory bulb, which is a structure located at the base of the brain. The olfactory bulb processes the incoming olfactory signals and helps to differentiate between different odors.


4.    Olfactory Cortex: From the olfactory bulb, the signals are relayed to the olfactory cortex, which is part of the brain's limbic system. The limbic system is involved in emotions, memory, and behavior, which is why smells can evoke strong emotional responses and trigger memories.


5. Perception: The brain integrates the information from the olfactory receptors, olfactory bulb, and olfactory cortex to create the perception of smell. Different odors activate specific patterns of neural activity in the brain, allowing us to distinguish between various smells and associate them with memories or emotions.


6. Behavioral Responses: Smell plays a crucial role in guiding behavior, such as identifying food, detecting danger, or recognizing familiar scents. The sense of smell can influence our preferences, mood, and even social interactions.


By deconstructing smell into its fundamental components and understanding how these components interact, researchers can gain insights into the mechanisms underlying olfaction and how the brain processes and interprets different odors. This knowledge can have implications for various fields, including neuroscience, psychology, and even product development (e.g., in the fragrance industry).

 

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