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Energy Manifold Natural Gradient Descent: From Riemannian Optimization to Modern Neuroscience, NeuroAI and Quantum Physics

Dr. Rishabh Pathak
When Geometry, Energy, Artificial Intelligence and Neuroscience Converge Modern Artificial Intelligence is rapidly moving beyond the idea that learning simply means minimizing an error function. Increasingly, researchers are asking a deeper question: what is the structure of the space in which learning takes place? This question becomes particularly important when the system being modelled is constrained, nonlinear, dynamic, or governed by physical principles. A recent work titled “Energy Manifold Natural Gradient Descent: Riemannian Optimization for Neural PDE Solvers” , by Zhangyong Liang and Huanhuan Gao, introduces Energy Manifold Natural Gradient Descent (EMNGD) , a mathematical framework that extends energy-based natural-gradient optimization from unconstrained Euclidean parameter spaces to constrained Riemannian parameter manifolds . At its core, the framework proposes a simple but powerful principle: An optimization algorithm should not only determine how to reduce error; it sh...
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Lateral Gaze Artifact

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Dr. Rishabh Pathak

Lateral gaze artifacts in EEG recordings occur during eye movements towards the sides.

Nature of Lateral Gaze Artifacts:

o  Lateral gaze artifacts are produced by eye movements towards the sides, resulting in specific patterns in the EEG.

o  These artifacts are dependent on conjugate gaze, where each eye's dipole contributes to the artifact.

2.     Characteristics:

o  Lateral gaze artifacts typically exhibit positive and negative phase reversals at specific electrodes corresponding to the direction of gaze.

o    The field of lateral gaze artifacts is maximum across the temples and frontal poles, with a frequency usually less than 1 Hz.

o    The amplitude of lateral gaze artifacts is low, resembling an unstable baseline for the superimposed EEG activity.

3.     Differentiation:

o Lateral gaze artifacts can be distinguished by their waveform characteristics, which have a more abrupt transition between positive and negative slopes compared to blinks and eyelid flutter artifacts.

o Specific movement features, such as the direction of gaze and the resulting phase reversals at electrodes, help differentiate lateral gaze artifacts from other ocular artifacts and EEG patterns.

Understanding the characteristics and differentiation of lateral gaze artifacts is essential for accurate EEG interpretation, as these artifacts can mimic abnormal brain activity if not properly identified and distinguished from genuine EEG patterns.

 

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