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High Frequency Oscillations
High-frequency oscillations (HFO) are brain waves of the frequency faster than ~80 Hz, generated by neuronal cell population. High-frequency oscillations can be recorded during an electroencephalagram (EEG), local field potential (LFP) or electrocorticogram (ECoG) electrophysiology recordings. They are present in physiological state during sharp waves and ripples - oscillatory patterns involved in memory consolidation processes. HFOs are associated with pathophysiology of the brain like epileptic seizure and are often recorded during seizure onset. It makes a promising biomarker for the identification of the epileptogenic zone. Other studies points to the HFO role in psychiatric disorders and possible implications to psychotic episodes in schizophrenia. Background and history Traditional classification of the frequency bands, that are associated to different functions/states of the brain and consist of delta, theta, alpha, beta and gamma bands. Due to the limited capabiliti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HFO Wiki
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HFO may refer to: * HealthForceOntario * Heavy fuel oil * Hybrid fibre-optic * Hydrofluoroolefin, a refrigerant * Hydrous ferric oxides * Hypofluorous acid * Halbleiterwerk Frankfurt (Oder) * High-frequency oscillations * Hardy Family Office, a professional wrestling stable led by Matt Hardy Matthew Moore Hardy (born September 23, 1974) is an American Professional wrestling, professional wrestler and actor. He is signed to Total Nonstop Action Wrestling (TNA), where he a former List of TNA World Tag Team Champions, three time TNA Wor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electric Potential
Electric potential (also called the ''electric field potential'', potential drop, the electrostatic potential) is defined as electric potential energy per unit of electric charge. More precisely, electric potential is the amount of work (physics), work needed to move a test charge from a reference point to a specific point in a static electric field. The test charge used is small enough that disturbance to the field is unnoticeable, and its motion across the field is supposed to proceed with negligible acceleration, so as to avoid the test charge acquiring kinetic energy or producing radiation. By definition, the electric potential at the reference point is zero units. Typically, the reference point is Earth (electricity), earth or a point at infinity, although any point can be used. In classical electrostatics, the electrostatic field is a vector quantity expressed as the gradient of the electrostatic potential, which is a scalar (physics), scalar quantity denoted by or occasi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parkinson's Disease
Parkinson's disease (PD), or simply Parkinson's, is a neurodegenerative disease primarily of the central nervous system, affecting both motor system, motor and non-motor systems. Symptoms typically develop gradually and non-motor issues become more prevalent as the disease progresses. The motor symptoms are collectively called parkinsonism and include tremors, bradykinesia, spasticity, rigidity as well as postural instability (i.e., difficulty maintaining balance). Non-motor symptoms develop later in the disease and include behavior change (individual), behavioral changes or mental disorder, neuropsychiatric problems such as sleep abnormalities, psychosis, anosmia, and mood swings. Most Parkinson's disease cases are idiopathic disease, idiopathic, though contributing factors have been identified. Pathophysiology involves progressive nerve cell death, degeneration of nerve cells in the substantia nigra, a midbrain region that provides dopamine to the basal ganglia, a system invo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Brain Stimulation
Deep brain stimulation (DBS) is a type of neurostimulation therapy in which an implantable pulse generator is stereotactic surgery, surgically implanted subcutaneous tissue, below the skin of the chest and connected by Lead (electronics), leads to the brain to deliver controlled electrical charge, electrical impulses. These charges therapeutically disrupt and promote dysfunctional nervous system circuits bidirectionally in both ante- and retrograde signaling, retrograde directions. Though first developed for Parkinsonian tremor, the technology has since been adapted to a wide variety of chronic neurologic disorders. The usage of electrical stimulation to treat neurologic disorders dates back thousands of years to ancient Greece and Early Dynastic Period (Egypt), dynastic Egypt. The distinguishing feature of DBS, however, is that by taking advantage of the portability of lithium-ion battery technology, it is able to be used long term without the patient having to be Electrical wir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerebral Cortex
The cerebral cortex, also known as the cerebral mantle, is the outer layer of neural tissue of the cerebrum of the brain in humans and other mammals. It is the largest site of Neuron, neural integration in the central nervous system, and plays a key role in attention, perception, awareness, thought, memory, language, and consciousness. The six-layered neocortex makes up approximately 90% of the Cortex (anatomy), cortex, with the allocortex making up the remainder. The cortex is divided into left and right parts by the longitudinal fissure, which separates the two cerebral hemispheres that are joined beneath the cortex by the corpus callosum and other commissural fibers. In most mammals, apart from small mammals that have small brains, the cerebral cortex is folded, providing a greater surface area in the confined volume of the neurocranium, cranium. Apart from minimising brain and cranial volume, gyrification, cortical folding is crucial for the Neural circuit, brain circuitry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limbic System
The limbic system, also known as the paleomammalian cortex, is a set of brain structures located on both sides of the thalamus, immediately beneath the medial temporal lobe of the cerebrum primarily in the forebrain.Schacter, Daniel L. 2012. ''Psychology''.sec. 3.20 Its various components support a variety of functions including emotion, behavior, long-term memory, and olfaction. The limbic system is involved in lower order emotional processing of input from sensory systems and consists of the amygdala, mammillary bodies, stria medullaris, central gray and dorsal and ventral nuclei of Gudden. This processed information is often relayed to a collection of structures from the telencephalon, diencephalon, and mesencephalon, including the prefrontal cortex, cingulate gyrus, limbic thalamus, hippocampus including the parahippocampal gyrus and subiculum, nucleus accumbens (limbic striatum), anterior hypothalamus, ventral tegmental area, midbrain raphe nuclei, habenular commi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primary Visual Cortex
The visual cortex of the brain is the area of the cerebral cortex that processes visual information. It is located in the occipital lobe. Sensory input originating from the eyes travels through the lateral geniculate nucleus in the thalamus and then reaches the visual cortex. The area of the visual cortex that receives the sensory input from the lateral geniculate nucleus is the primary visual cortex, also known as visual area 1 ( V1), Brodmann area 17, or the striate cortex. The extrastriate areas consist of visual areas 2, 3, 4, and 5 (also known as V2, V3, V4, and V5, or Brodmann area 18 and all Brodmann area 19). Both hemispheres of the brain include a visual cortex; the visual cortex in the left hemisphere receives signals from the right visual field, and the visual cortex in the right hemisphere receives signals from the left visual field. Introduction The primary visual cortex (V1) is located in and around the calcarine fissure in the occipital lobe. Each hemi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dendrite
A dendrite (from Ancient Greek language, Greek δένδρον ''déndron'', "tree") or dendron is a branched cytoplasmic process that extends from a nerve cell that propagates the neurotransmission, electrochemical stimulation received from other neural cells to the cell body, or soma (biology), soma, of the neuron from which the dendrites project. Electrical stimulation is transmitted onto dendrites by upstream neurons (usually via their axons) via synapses which are located at various points throughout the dendritic tree. Dendrites play a critical role in integrating these synaptic inputs and in determining the extent to which action potentials are produced by the neuron. Structure and function Dendrites are one of two types of cytoplasmic processes that extrude from the cell body of a neuron, the other type being an axon. Axons can be distinguished from dendrites by several features including shape, length, and function. Dendrites often taper off in shape and are shorter, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hippocampus Proper
The hippocampal subfields are four subfields CA1, CA2, CA3, and CA4 that make up the structure of the hippocampus. Regions described in the hippocampus are the head, body, and tail, and other hippocampal subfields include the dentate gyrus, the presubiculum, and the subiculum. The CA subfields use the initials of Hippocampus#Name, cornu ammonis, an earlier name of the hippocampus. Structure There are four hippocampal subfields, in the hippocampus proper which form a neural circuit called the trisynaptic circuit. CA1 CA1 is the first region in the hippocampal circuit, from which a significant output pathway goes to layer V of the entorhinal cortex. The main output of CA1 is to the subiculum. CA2 CA2 is a small region located between CA1 and CA3. It receives some input from layer II of the entorhinal cortex via the perforant path. Its pyramidal cells are more like those in CA3 than those in CA1. It is often ignored due to its small size. CA3 CA3 receives input from the mossy fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyramidal Cells
Pyramidal cells, or pyramidal neurons, are a type of multipolar neuron found in areas of the brain including the cerebral cortex, the hippocampus, and the amygdala. Pyramidal cells are the primary excitation units of the mammalian prefrontal cortex and the corticospinal tract. One of the main structural features of the pyramidal neuron is the conic shaped soma, or cell body, after which the neuron is named. Other key structural features of the pyramidal cell are a single axon, a large apical dendrite, multiple basal dendrites, and the presence of dendritic spines. Pyramidal neurons are also one of two cell types where the characteristic sign, Negri bodies, are found in post-mortem rabies infection. Pyramidal neurons were first discovered and studied by Santiago Ramón y Cajal. Since then, studies on pyramidal neurons have focused on topics ranging from neuroplasticity to cognition. Structure One of the main structural features of the pyramidal neuron is the conic shape ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biological Neuron Model
Biological neuron models, also known as spiking neuron models, are mathematical descriptions of the conduction of electrical signals in neurons. Neurons (or nerve cells) are electrically excitable cells within the nervous system, able to fire electric signals, called action potentials, across a neural network. These mathematical models describe the role of the biophysical and geometrical characteristics of neurons on the conduction of electrical activity. Central to these models is the description of how the membrane potential (that is, the difference in electric potential between the interior and the exterior of a biological cell) across the cell membrane changes over time. In an experimental setting, stimulating neurons with an electrical current generates an action potential (or spike), that propagates down the neuron's axon. This axon can branch out and connect to a large number of downstream neurons at sites called synapses. At these synapses, the spike can cause the re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
