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Thalamocortical Radiations
In neuroanatomy, thalamocortical radiations are the fibers between the thalamus and the cerebral cortex. Structure Thalamocortical (TC) fibers have been referred to as one of the two constituents of the isothalamus, the other being micro neurons. Thalamocortical fibers have a bush or tree-like appearance as they extend into the internal capsule and project to the layers of the cortex. The main thalamocortical fibers extend from different nuclei of the thalamus and project to the visual cortex, somatosensory (and associated sensori-motor) cortex, and the auditory cortex in the brain. Thalamocortical radiations also innervate gustatory and olfactory pathways, as well as pre-frontal motor areas. Visual input from the optic tract is processed by the lateral geniculate nucleus of the thalamus, auditory input in the medial geniculate nucleus, and somatosensory input in the ventral posterior nucleus of the thalamus. Thalamic nuclei project to cortical areas of distinct architectural or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalamus
The thalamus (from Greek θάλαμος, "chamber") is a large mass of gray matter located in the dorsal part of the diencephalon (a division of the forebrain). Nerve fibers project out of the thalamus to the cerebral cortex in all directions, allowing hub-like exchanges of information. It has several functions, such as the relaying of sensory signals, including motor signals to the cerebral cortex and the regulation of consciousness, sleep, and alertness. Anatomically, it is a paramedian symmetrical structure of two halves (left and right), within the vertebrate brain, situated between the cerebral cortex and the midbrain. It forms during embryonic development as the main product of the diencephalon, as first recognized by the Swiss embryologist and anatomist Wilhelm His Sr. in 1893. Anatomy The thalamus is a paired structure of gray matter located in the forebrain which is superior to the midbrain, near the center of the brain, with nerve fibers projecting out to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glutamate
Glutamic acid (symbol Glu or E; the ionic form is known as glutamate) is an α-amino acid that is used by almost all living beings in the biosynthesis of proteins. It is a non-essential nutrient for humans, meaning that the human body can synthesize enough for its use. It is also the most abundant excitatory neurotransmitter in the vertebrate nervous system. It serves as the precursor for the synthesis of the inhibitory gamma-aminobutyric acid (GABA) in GABA-ergic neurons. Its molecular formula is . Glutamic acid exists in three optically isomeric forms; the dextrorotatory -form is usually obtained by hydrolysis of gluten or from the waste waters of beet-sugar manufacture or by fermentation.Webster's Third New International Dictionary of the English Language Unabridged, Third Edition, 1971. Its molecular structure could be idealized as HOOC−CH()−()2−COOH, with two carboxyl groups −COOH and one amino group −. However, in the solid state and mildly acidic water solu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcarine Fissure
The calcarine sulcus (or calcarine fissure) is an anatomical landmark located at the caudal end of the medial surface of the brain of humans and other primates. Its name comes from the Latin "calcar" meaning "spur". It is very deep, and known as a complete sulcus. Structure The calcarine sulcus begins near the occipital pole in two converging rami. It runs forward to a point a little below the splenium of the corpus callosum. Here, it is joined at an acute angle by the medial part of the parieto-occipital sulcus. The anterior part of this sulcus gives rise to the prominence of the calcar avis in the posterior cornu of the lateral ventricle. The cuneus is above the calcarine sulcus, while the lingual gyrus is below it. Development In humans, the calcarine sulcus usually becomes visible between 20 weeks and 28 weeks of gestation. Function The calcarine sulcus is associated with visual cortex. It is where the primary visual cortex (V1) is concentrated. The central visual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superior Colliculus
In neuroanatomy, the superior colliculus () is a structure lying on the roof of the mammalian midbrain. In non-mammalian vertebrates, the homologous structure is known as the optic tectum, or optic lobe. The adjective form ''tectal'' is commonly used for both structures. In mammals, the superior colliculus forms a major component of the midbrain. It is a paired structure and together with the paired inferior colliculi forms the corpora quadrigemina. The superior colliculus is a layered structure, with a pattern that is similar to all mammals. The layers can be grouped into the superficial layers ( stratum opticum and above) and the deeper remaining layers. Neurons in the superficial layers receive direct input from the retina and respond almost exclusively to visual stimuli. Many neurons in the deeper layers also respond to other modalities, and some respond to stimuli in multiple modalities. The deeper layers also contain a population of motor-related neurons, capable of activat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiple Sclerosis
Multiple (cerebral) sclerosis (MS), also known as encephalomyelitis disseminata or disseminated sclerosis, is the most common demyelinating disease, in which the insulating covers of nerve cells in the brain and spinal cord are damaged. This damage disrupts the ability of parts of the nervous system to transmit signals, resulting in a range of signs and symptoms, including physical, mental, and sometimes psychiatric problems. Specific symptoms can include double vision, blindness in one eye, muscle weakness, and trouble with sensation or coordination. MS takes several forms, with new symptoms either occurring in isolated attacks (relapsing forms) or building up over time (progressive forms). In the relapsing forms of MS, between attacks, symptoms may disappear completely, although some permanent neurological problems often remain, especially as the disease advances. While the cause is unclear, the underlying mechanism is thought to be either destruction by the immune system ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nociception
Nociception (also nocioception, from Latin ''nocere'' 'to harm or hurt') is the sensory nervous system's process of encoding noxious stimuli. It deals with a series of events and processes required for an organism to receive a painful stimulus, convert it to a molecular signal, and recognize and characterize the signal in order to trigger an appropriate defense response. In nociception, intense chemical (e.g., capsaicin present in Chili pepper or Cayenne pepper), mechanical (e.g., cutting, crushing), or thermal (heat and cold) stimulation of sensory neurons called nociceptors produces a signal that travels along a chain of nerve fibers via the spinal cord to the brain. Nociception triggers a variety of physiological and behavioral responses to protect the organism against an aggression and usually results in a subjective experience, or perception, of pain in sentient beings. Detection of noxious stimuli Potentially damaging mechanical, thermal, and chemical stimuli are detected ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Postcentral Gyrus
In neuroanatomy, the postcentral gyrus is a prominent gyrus in the lateral parietal lobe of the human brain. It is the location of the primary somatosensory cortex, the main sensory receptive area for the somatosensory system, sense of touch. Like other sensory areas, there is a map of sensory space in this location, called the ''sensory homunculus''. The primary somatosensory cortex was initially defined from surface stimulation studies of Wilder Penfield, and parallel surface potential studies of Bard, Woolsey, and Marshall. Although initially defined to be roughly the same as Brodmann areas Brodmann area 3, 3, Brodmann area 1, 1 and Brodmann area 2, 2, more recent work by Jon Kaas, Kaas has suggested that for homogeny with other sensory fields only area 3 should be referred to as "primary somatosensory cortex", as it receives the bulk of the Thalamocortical radiations, thalamocortical projections from the sensory input fields. Structure The lateral postcentral gyrus is bounded ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lateral Posterior Nucleus Of Thalamus
The lateral posterior nucleus is a nucleus of the thalamus The thalamus (from Greek θάλαμος, "chamber") is a large mass of gray matter located in the dorsal part of the diencephalon (a division of the forebrain). Nerve fibers project out of the thalamus to the cerebral cortex in all directions, .... It acts in concert with the pulvinar. In rodents, the lateral posterior nucleus is considered the homologue of the primate pulvinar. References External links * http://brainmaps.org/index.php?y=lateral+posterior+nucleus+of+thalamus {{Authority control Pulvinar nuclei Lateral nuclei of the thalamus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ventral Posteromedial Nucleus
The ventral posteromedial nucleus (VPM) is a nucleus of the thalamus. Inputs and outputs The VPM contains synapses between second and third order neurons from the anterior (ventral) trigeminothalamic tract and posterior (dorsal) trigeminothalamic tract. These neurons convey sensory information from the face and oral cavity. Third order neurons in the trigeminothalamic systems project to the postcentral gyrus. The VPM also receives taste afferent information from the solitary tract The solitary tract (tractus solitarius, or fasciculus solitarius), is a compact fiber bundle that extends longitudinally through the posterolateral region of the medulla oblongata. The solitary tract is surrounded by the solitary nucleus, and des ... and projects to the cortical gustatory area. Subareas VPMpc The parvicellular part of the ventroposterior medial nucleus (VPMpc) is argued by some as not an actually part of the VPM, because it does not project to the somatosensory cortex as the r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ventral Posterolateral Nucleus
The ventral posterolateral nucleus (VPL) is a nucleus of the thalamus. Together with the ventral posteromedial nucleus (VPM), ventral posterior inferior nucleus (VPI) and ventromedial posterior nucleus (VMpo), it constitutes the ventral posterior nucleus. There is uncertainty in the location of VMpo, as determined by spinothalamic tract (STT) terminations and staining for calcium-binding proteins, and several authorities do not consider its existence as being proved. The nucleus ventralis posterior lateralis pars oralis (VPLo) is a subdivision of the ventral posterolateral thalamus which has substantial projections to the motor cortex. Input and output The VPL receives information from the neospinothalamic tract and the medial lemniscus of the posterior column-medial lemniscus pathway. It then projects this sensory information to Brodmann's Areas 3, 1 and 2 in the postcentral gyrus. Collectively, Brodmann areas 3, 1 and 2 make up the primary somatosensory In physiology, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
European Journal Of Neuroscience
The ''European Journal of Neuroscience'' is a biweekly peer-reviewed scientific journal covering all aspects of neuroscience. It was established in 1989 with Ray Guillery (then at the University of Oxford) as the founding editor-in-chief. The editor-in-chief is John J. Foxe (University of Rochester) The journal is published by Wiley-Blackwell on behalf of the Federation of European Neuroscience Societies. According to the ''Journal Citation Reports'', the journal has a 2020 impact factor of 3.386. Authors can elect to have accepted articles published as open access. EJN adopted transparent peer-review in January 2017. Sections Articles will appear within one of the five sections of the journal: * Molecular and Synaptic Mechanisms * Systems Neuroscience * Behavioural Neuroscience * Cognitive Neuroscience * Clinical and Translational Neuroscience Features EJN also publishespecialanissues related to topical issue in neuroscience. Editors-in-chief The following persons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 capabilities ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
