Skip to main content

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...

How the Force is transmitted to the Bones

The transmission of force from muscles to bones is a crucial aspect of human movement and biomechanics. This process involves the conversion of muscle contraction forces into joint movements and ultimately the generation of mechanical loads on the skeletal system. The following points explain how force is transmitted from muscles to bones:

Transmission of Force from Muscles to Bones:

1.    Tendon Attachment:

o    Tendon Structure:

§  Tendons are dense connective tissues that connect muscles to bones, serving as the primary means of transmitting force.

§  Muscle contraction generates tension in the tendons, which is then transmitted to the bones through the tendon-bone interface.

2.    Tendon-Bone Junction:

o    Enthesis Structure:

§  The enthesis is the specialized region where tendons or ligaments attach to bone, optimizing force transmission and load distribution.

§  The enthesis structure includes fibrocartilage and mineralized fibrocartilage zones that help to anchor the tendon to the bone and withstand tensile forces.

3.    Mechanical Coupling:

o    Force Transfer:

§  The mechanical coupling between muscles, tendons, and bones allows for efficient force transmission during muscle contractions.

§  Tendons act as compliant structures that store and release elastic energy, enhancing the efficiency of force transmission to the skeletal system.

4.    Muscle-Tendon Unit:

o    Functional Unit:

§  The muscle-tendon unit functions as a coordinated system where muscle contraction generates tension in the tendon, leading to joint movement and force application on the bones.

§  The length-tension relationship of the muscle-tendon unit influences the force transmission capacity and joint stability during movement.

5.    Biomechanical Pathways:

o    Force Distribution:

§  Forces generated by muscles are transmitted through tendons to the bones along specific biomechanical pathways based on muscle architecture and joint mechanics.

§  The orientation of muscle fibers, tendon insertion angles, and joint geometry influence the direction and magnitude of force transmission.

6.    Lever Systems:

o    Mechanical Advantage:

§  Muscles and tendons act as components of lever systems within the musculoskeletal system, providing mechanical advantage for force transmission.

§  The arrangement of bones, joints, and muscle-tendon units determines the leverage and efficiency of force transmission for producing joint movements.

7.    Joint Loading:

o    Load Distribution:

§  Force transmission from muscles to bones results in joint loading, where mechanical loads are distributed across the articular surfaces of the bones.

§  Proper force transmission is essential for maintaining joint stability, preventing injury, and optimizing movement efficiency.

Understanding the mechanisms of force transmission from muscles to bones is essential for biomechanical analyses, sports performance optimization, rehabilitation strategies, and injury prevention. The coordinated interactions between muscles, tendons, and bones ensure effective force transfer, joint motion control, and overall musculoskeletal function during various activities and movements.
 

Comments

Popular posts from this blog

Cancellous Bone

Cancellous bone, also known as trabecular or spongy bone, is the other main type of bone tissue found in the human skeleton alongside cortical bone. Cancellous bone has a porous and lattice-like structure, providing flexibility, shock absorption, and a site for hematopoiesis (blood cell formation). Here are key features and characteristics of cancellous bone: 1.     Structure : o     Trabeculae : Cancellous bone is composed of a network of thin, bony trabeculae that form an interconnected lattice structure. o     Bone Marrow : The spaces between trabeculae contain red bone marrow, which is involved in the production of blood cells (hematopoiesis). o     Less Compact : Cancellous bone is less dense and compact than cortical bone, with a higher surface area-to-volume ratio. 2.     Composition : o     Trabecular Bone : The trabeculae are made up of lamellae, osteocytes, and canaliculi similar to corti...

Amphiarthrodial or Cartilaginous Joints

Amphiarthrodial joints, also known as cartilaginous joints, are joints where the adjacent bones are connected by cartilage. These joints allow for limited movement and provide both stability and flexibility to the skeletal system. Here is an overview of amphiarthrodial or cartilaginous joints: Amphiarthrodial or Cartilaginous Joints: 1.     Structure : o     Cartilage : §   Amphiarthrodial joints are characterized by the presence of cartilage between the articulating surfaces of the bones. §   The cartilage can be hyaline cartilage or fibrocartilage, depending on the specific joint and its function. o     Lack of Joint Cavity : §   Similar to fibrous joints, cartilaginous joints do not have a synovial cavity, and the bones are held together by the cartilaginous tissue. 2.     Types : o     Synchondroses : §   Synchondroses are cartilaginous joints where the connecting material is hyaline carti...

Review Settings of EEG

The review settings of an EEG recording refer to the parameters that can be adjusted to optimize the visualization and interpretation of electrical brain activity. Here is an overview of the key review settings in EEG analysis: 1.       Amplification (Gain/Sensitivity) : o Definition : Amplification, also known as gain or sensitivity, determines how much the electrical signals from the brain are amplified before being displayed on the EEG recording. o Measurement : Typically measured in microvolts per millimeter (μV/mm). o Impact : Adjusting the amplification setting can affect the visibility of high-amplitude and low-amplitude activity. High-amplitude activity may require vertical compression to fit within the display range, while low-amplitude activity may require lower sensitivity settings for better visualization. 2.      Frequency Filtering : o Bandpass : The frequency range within which EEG signals are analyzed. Common settings include ...

Cell Maturation (Dendrite and Axon Growth)

Cell maturation, encompassing dendrite and axon growth, is a crucial stage of brain development where neurons undergo structural changes to establish connections and form functional neural circuits. Here is an overview of cell maturation in the context of dendrite and axon growth: 1.      Dendrite Growth : o     Definition : Dendrites are branched extensions of a neuron that receive signals from other neurons and transmit these signals to the cell body. o     Dendritic Arborization : During maturation, neurons extend and elaborate their dendritic arbors, increasing the surface area available for synaptic connections. o     Synaptic Integration : Dendritic growth is essential for forming synapses with other neurons, allowing for the integration of incoming signals and information processing. o     Activity-Dependent Plasticity : Dendritic growth can be influenced by neural activity and sensory experiences, sh...

Distinguishing Features of Electrode Artifacts

Electrode artifacts in EEG recordings can present with distinct features that differentiate them from genuine brain activity.  1.      Types of Electrode Artifacts : o Variety : Electrode artifacts encompass several types, including electrode pop, electrode contact, electrode/lead movement, perspiration artifacts, salt bridge artifacts, and movement artifacts. o Characteristics : Each type of electrode artifact exhibits specific waveform patterns and spatial distributions that aid in their identification and differentiation from true EEG signals. 2.    Electrode Pop : o Description : Electrode pop artifacts are characterized by paroxysmal, sharply contoured transients that interrupt the background EEG activity. o Localization : These artifacts typically involve only one electrode and lack a field indicating a gradual decrease in potential amplitude across the scalp. o Waveform : Electrode pop waveforms have a rapid rise and a slower fall compared to in...