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...

Theta Burst Stimulation (TBS)

Theta Burst Stimulation (TBS) is a form of repetitive transcranial magnetic stimulation (rTMS) that has gained attention in neuroscience and clinical research for its ability to modulate cortical excitability and induce lasting effects on brain function. Here is an overview of Theta Burst Stimulation (TBS):


1.      Definition:

oTheta Burst Stimulation (TBS) is a patterned form of repetitive transcranial magnetic stimulation (rTMS) that involves delivering bursts of magnetic pulses at a specific frequency (typically theta frequency, around 5 Hz) to targeted regions of the brain.

2.     Types of TBS:

o    There are two main types of Theta Burst Stimulation:

§ Continuous Theta Burst Stimulation (cTBS): Involves continuous bursts of stimulation over a period of time, typically leading to inhibitory effects on cortical excitability.

§Intermittent Theta Burst Stimulation (iTBS): Involves intermittent bursts of stimulation with short breaks in between, often resulting in facilitatory effects on cortical excitability.

3.     Effects on Cortical Excitability:

oTBS protocols have been shown to induce changes in cortical excitability that outlast the stimulation period. Inhibitory TBS can lead to long-term depression (LTD) of synaptic activity, while facilitatory TBS can induce long-term potentiation (LTP), resembling mechanisms of synaptic plasticity.

4.    Research and Therapeutic Applications:

oTBS has been widely used in research settings to investigate neural plasticity, motor learning, and cognitive functions. It is also being explored as a potential therapeutic tool for various neurological and psychiatric conditions.

5.     Clinical Applications:

oTBS has shown promise in the treatment of neurological and psychiatric disorders, including depression, schizophrenia, chronic pain, stroke rehabilitation, and movement disorders like Parkinson's disease. It is being studied as a non-invasive neuromodulation technique with potential therapeutic benefits.

6.    Targeted Brain Regions:

oTBS can be applied to specific brain regions based on the research or clinical objectives. Common targets include the primary motor cortex (M1), dorsolateral prefrontal cortex (DLPFC), cerebellum, and other areas implicated in motor control, mood regulation, and cognitive functions.

7.     Safety and Efficacy:

oTBS is generally considered safe when administered by trained professionals following established protocols. It is non-invasive and well-tolerated by most individuals. However, individual responses to TBS may vary, and its long-term effects are still being studied.

In summary, Theta Burst Stimulation (TBS) is a specialized form of repetitive transcranial magnetic stimulation that can modulate cortical excitability and induce lasting changes in brain function. Its potential applications in research and clinical settings make it a valuable tool for studying neural plasticity and exploring therapeutic interventions for various neurological and psychiatric conditions.

 

Comments

Popular posts from this blog

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...

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...

Unrestricted Sampling

Unrestricted sampling, also known as simple random sampling, is a fundamental sampling technique where each element in the population has an equal and independent chance of being selected for the sample. In unrestricted sampling: 1.     Equal Probability of Selection : §   In simple random sampling, every element in the population has an equal probability of being chosen for the sample. This ensures that each unit is selected independently of other units, without any bias towards specific elements. 2.     Random Selection : §   The selection of sample elements is done randomly, without any systematic pattern or predetermined order. This randomness is essential to ensure that the sample is representative of the population and to minimize selection bias. 3.     Independence of Selection : §   Each selection is made independently of previous selections, meaning that the inclusion or exclusion of one element does not influence the ...

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...

What is anthropometric system in biomechanics?

  In biomechanics, the anthropometric system refers to the measurement and analysis of the physical dimensions, proportions, and characteristics of the human body. Anthropometry plays a crucial role in understanding human movement, ergonomics, sports performance, and injury prevention by providing valuable data on body segment lengths, joint centers, muscle attachment points, and other anatomical parameters. The anthropometric system involves the following key components: 1.      Body Segment Lengths : Anthropometric measurements are used to determine the lengths of various body segments such as the arms, legs, trunk, and head. These segment lengths are essential for calculating joint angles, lever arms, and moment arms during movement analysis. 2.     Joint Centers : By identifying the locations of joint centers (e.g., hip, knee, ankle), researchers and practitioners can accurately assess joint kinematics and kinetics during activities like w...