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

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...

What is fMRI ?

  Functional Magnetic Resonance Imaging (fMRI) is a non-invasive neuroimaging technique that measures brain activity by detecting changes in blood flow and oxygen levels in response to neural activity. fMRI is widely used in neuroscience and cognitive psychology to study brain function and connectivity during various tasks, behaviors, and resting states. Key features of fMRI include: 1.      Principle of fMRI : o     fMRI is based on the principle that changes in neural activity are accompanied by changes in blood flow and oxygenation levels in the brain. o     When a specific brain region becomes active, it requires more oxygenated blood to support the increased metabolic demands of neural activity. o     The fMRI scanner detects these changes in blood oxygen level-dependent (BOLD) signals, providing a measure of brain activity in different regions. 2.      Task-Based fMRI : o  ...

What is EEG?

  Electroencephalography (EEG) is a technique used to record the electrical activity of the brain. It involves placing electrodes on the scalp to detect and measure the electrical signals produced by brain cells, known as neurons. These electrodes pick up the electrical impulses generated by the brain's neurons, which communicate with each other through electrical activity. The EEG signals are then amplified and recorded, allowing researchers and clinicians to analyze the brain's electrical patterns. EEG is a non-invasive method that provides real-time information about brain activity. It is commonly used in various fields, including neuroscience, clinical neurology, psychology, and cognitive science. By studying EEG signals, researchers can investigate brain function, cognitive processes, and neurological disorders. Different brain wave patterns, such as alpha, beta, delta, and theta waves, are associated with different states of consciousness, cognitive tasks, and brain f...

Basic Model of Human Connectome Project

  The Human Connectome Project (HCP) employs a comprehensive and multi-modal approach to map the structural and functional connectivity of the human brain. The basic model of the HCP involves the following key components: Data Acquisition : The HCP collects neuroimaging data from a large cohort of healthy individuals using state-of-the-art imaging techniques. Structural MRI: High-resolution structural MRI scans are acquired to visualize the anatomical features of the brain, such as gray matter, white matter, and cortical thickness. Diffusion MRI: Diffusion MRI is used to map the white matter pathways in the brain by tracking the diffusion of water molecules along axonal fibers. Functional MRI: Resting-state fMRI and task-based fMRI are employed to study the functional connectivity and activity patterns of the brain at rest and during specific cognitive tasks. Data Processing and Analysis : The ...

Human Connectome Project

The Human Connectome Project (HCP) is a large-scale research initiative that aims to map the structural and functional connectivity of the human brain. Launched in 2009, the HCP utilizes advanced neuroimaging techniques to create detailed maps of the brain's neural pathways and networks in healthy individuals. The project focuses on understanding how different regions of the brain communicate and interact with each other, providing valuable insights into brain function and organization. 1.      Structural Connectivity : The HCP uses diffusion MRI to map the white matter pathways in the brain, revealing the structural connections between different brain regions. This information helps researchers understand the physical wiring of the brain and how information is transmitted between regions. 2.      Functional Connectivity : Functional MRI (fMRI) is employed to study the patterns of brain activity and connectivity while individuals are at rest (...

Brain Mapping

  Brain mapping refers to the process of creating detailed representations or maps of the structure, function, and connectivity of the human brain. Various techniques and approaches are used in brain mapping to study different aspects of brain organization and activity. Here are some key methods and concepts related to brain mapping: 1.      Structural Brain Mapping : §   MRI-based Structural Imaging : Techniques like structural MRI (sMRI) provide high-resolution images of the brain's anatomy, allowing researchers to visualize and study brain structures such as gray matter, white matter, and cortical regions. §   Diffusion Tensor Imaging (DTI) : DTI is used to map the brain's white matter tracts and study the connectivity between different brain regions based on the diffusion of water molecules along axonal pathways. 2.      Functional Brain Mapping : §   Functional MRI (fMRI) : fMRI measures changes in blood flow and oxygenati...

What is Brain Stimulation and its applications in research world?

  Brain Stimulation is a field of neuroscience that involves the use of various techniques to modulate brain activity non-invasively. This can include methods such as transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), and deep brain stimulation (DBS). These techniques are used to study brain function, investigate neurological disorders, and potentially treat conditions such as depression, chronic pain, and movement disorders. Brain stimulation has shown promise in enhancing cognitive abilities, promoting neuroplasticity, and modulating neural circuits.  Here are some applications of brain stimulation in the research world: 1.      Neuroscientific Research : Brain stimulation techniques are widely used in neuroscience research to investigate brain function, neural circuits, and the underlying mechanisms of various cognitive processes. Researchers can manipulate brain activity in specific regions to study their role i...

How the Neural network circuits works in Parkinson's Disease?

  In Parkinson's disease, the neural network circuits involved in motor control are disrupted, leading to characteristic motor symptoms such as tremor, bradykinesia, and rigidity. The primary brain regions affected in Parkinson's disease include the basal ganglia and the cortex. Here is an overview of how neural network circuits work in Parkinson's disease: 1.      Basal Ganglia Dysfunction: The basal ganglia are a group of subcortical nuclei involved in motor control. In Parkinson's disease, there is a loss of dopamine-producing neurons in the substantia nigra, leading to decreased dopamine levels in the basal ganglia. This dopamine depletion results in abnormal signaling within the basal ganglia circuitry, leading to motor symptoms. 2.      Cortical Involvement: The cortex, particularly the motor cortex, plays a crucial role in initiating and coordinating voluntary movements. In Parkinson's disease, abnormal activity in the cortex, especial...