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Mamillary Bodies
The mammillary bodies also mamillary bodies, are a pair of small round brainstem nuclei. They are located on the undersurface of the brain that, as part of the diencephalon, form part of the limbic system. They are located at the ends of the anterior arches of the fornix. They consist of two groups of nuclei, the medial mammillary nuclei and the lateral mammillary nuclei. Neuroanatomists have often categorized the mammillary bodies as part of the posterior part of hypothalamus. Structure Connections They are connected to other parts of the brain (as shown in the schematic, below left), and act as a relay for impulses coming from the amygdalae and hippocampi, via the mamillothalamic tract to the thalamus. The lateral mammillary nucleus has bidirectional connections with the dorsal tegmental nucleus. The medial mammillary nucleus connects with the ventral tegmental nucleus. Function File:Slide5dd.JPG, Mammillary body Mammillary bodies, and their projections to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
:en:Henry Gray
Henry Gray (1827 – 13 June 1861) was a British anatomist and surgeon most notable for publishing the book ''Gray's Anatomy''. He was elected a Fellow of the Royal Society (FRS) at the age of 25. Biography Gray was born in Belgravia, London, in 1827 and lived most of his life in London. In 1842, he entered as a student at St. George's Hospital, London (then situated in Belgravia, now moved to Tooting), and he is described by those who knew him as a most painstaking and methodical worker, and one who learned his anatomy by the slow but invaluable method of making dissections for himself. While still a student, Gray secured the triennial prize of Royal College of Surgeons in 1848 for an essay entitled ''The Origin, Connexions and Distribution of nerves to the human eye and its appendages, illustrated by comparative dissections of the eye in other vertebrate animals.'' In 1852, at the early age of 25, he was elected a Fellow of the Royal Society, and in the followin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mamillothalamic Tract
The mammillothalamic tract (MMT) (also mammillary fasciculus, mammillothalamic fasciculus, thalamomammillary fasciculus, bundle of Vicq d'Azyr) is an efferent pathway of the mammillary bodies which project to the anterior nuclei of the thalamus. The mammillothalamic tract is part of the Papez circuit (involved in spatial memory), starting and finishing in the hippocampus.Shah, A., Jhawar, S. S., & Goel, A. (2012). Analysis of the anatomy of the Papez circuit and adjoining limbic system by fiber dissection techniques. rticle Journal of Clinical Neuroscience, 19(2), 289-298. . The fibers of the MMT are heavily myelinated. It arises from the medial and lateral nuclei of the mammillary bodies, and from fibers that are directly continued from the fornix of the hippocampus. It connects the mammillary bodies to the dorsal tegmental nuclei, the ventral tegmental nuclei, and the anterior thalamic nuclei. Structure Axons divide within the gray matter; the thicker fibres form the MTT ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colloid Cysts
A colloid cyst is a non-malignant neoplasm, tumor in the brain. It consists of a gelatinous material contained within a membrane of epithelial tissue. It is almost always found just posterior to the foramen of Monro in the anterior aspect of the third ventricle, originating from the roof of the ventricle. Because of its location, it can cause obstructive hydrocephalus and increased intracranial pressure. Colloid cysts represent 0.5–1.0% of intracranial tumors. Symptoms can include headache, Vertigo (medical), vertigo, memory deficits, diplopia, behavioral disturbances, and in extreme cases, sudden death. Intermittency of symptoms is characteristic of this lesion. Untreated pressure caused by these cysts can result in brain herniation. Colloid cyst symptoms have been associated with four variables: cyst size, cyst imaging characteristics, ventricular size, and patient age. Their developmental origin is unclear, though they may be of endodermal origin, which would explain the muc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amnesia
Amnesia is a deficit in memory caused by brain damage or brain diseases,Gazzaniga, M., Ivry, R., & Mangun, G. (2009) Cognitive Neuroscience: The biology of the mind. New York: W.W. Norton & Company. but it can also be temporarily caused by the use of various sedative and hypnotic drugs. The memory can be either wholly or partially lost due to the extent of damage that is caused. There are two main types of amnesia: * Retrograde amnesia is the inability to remember information that was acquired before a particular date, usually the date of an accident or operation. In some cases, the memory loss can extend back decades, while in other cases, people may lose only a few months of memory. * Anterograde amnesia is the inability to transfer new information from the short-term store into the long-term store. People with anterograde amnesia cannot remember things for long periods of time. These two types are not mutually exclusive; both can also occur simultaneously. Case stud ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anterograde Amnesia
In neurology, anterograde amnesia is the inability to create new memories after an event that caused amnesia, leading to a partial or complete inability to recall the recent past, while long-term memories from before the event remain intact. This is in contrast to retrograde amnesia, where memories created prior to the event are lost while new memories can still be created. Both can occur together in the same patient. To a large degree, anterograde amnesia remains a mysterious ailment because the precise mechanism of storing memories is not yet well understood, although it is known that the regions of the brain involved are certain sites in the temporal cortex, especially in the hippocampus and nearby subcortical regions. Signs and symptoms People with anterograde amnesic syndromes may present widely varying degrees of forgetfulness. Some with severe cases have a combined form of anterograde and retrograde amnesia, sometimes called global amnesia. In the case of drug-induce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Memory
Memory is the faculty of the mind by which data or information is encoded, stored, and retrieved when needed. It is the retention of information over time for the purpose of influencing future action. If past events could not be remembered, it would be impossible for language, relationships, or personal identity to develop. Memory loss is usually described as forgetfulness or amnesia. Memory is often understood as an informational processing system with explicit and implicit functioning that is made up of a sensory processor, short-term (or working) memory, and long-term memory. This can be related to the neuron. The sensory processor allows information from the outside world to be sensed in the form of chemical and physical stimuli and attended to various levels of focus and intent. Working memory serves as an encoding and retrieval processor. Information in the form of stimuli is encoded in accordance with explicit or implicit functions by the working memory p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wernicke–Korsakoff Syndrome
Wernicke-Korsakoff syndrome (WKS), colloquially referred to as wet brain syndrome, is the combined presence of Wernicke encephalopathy (WE) and Korsakoff syndrome. Due to the close relationship between these two disorders, people with either are usually diagnosed with WKS as a single syndrome. It mainly causes vision changes, ataxia and impaired memory. The cause of the disorder is thiamine deficiency, thiamine (vitamin B1) deficiency. This can occur due to eating disorders, malnutrition, and alcohol abuse. These disorders may manifest together or separately. WKS is usually secondary to prolonged alcohol abuse. Wernicke encephalopathy and WKS are most commonly seen in people with an alcohol use disorder. Failure in diagnosis of WE and thus treatment of the disease leads to death in approximately 20% of cases, while 75% are left with permanent brain damage associated with WKS. Of those affected, 25% require long-term institutionalization in order to receive effective care. S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiamine
Thiamine, also known as thiamin and vitamin B1, is a vitamin – an Nutrient#Micronutrients, essential micronutrient for humans and animals. It is found in food and commercially synthesized to be a dietary supplement or medication. Phosphorylated forms of thiamine are required for some Metabolism, metabolic reactions, including the breakdown of Carbohydrate metabolism, glucose and amino acids. Food sources of thiamine include whole grains, legumes, and some meats and fish. Refined grain, Grain processing removes much of the vitamin content, so in many countries cereals and flours are food fortification, enriched with thiamine. Supplements and medications are available to treat and prevent thiamine deficiency and the disorders that result from it such as Thiamine deficiency#Dry beriberi, beriberi and Wernicke encephalopathy. They are also used to treat maple syrup urine disease and Leigh syndrome. Supplements and medications are typically taken Route of administration#Oral ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Episodic Memory
Episodic memory is the memory of everyday events (such as times, location geography, associated emotions, and other contextual information) that can be explicitly stated or conjured. It is the collection of past personal experiences that occurred at particular times and places; for example, the party on one's 7th birthday. Along with semantic memory, it comprises the category of explicit memory, one of the two major divisions of long-term memory (the other being implicit memory). The term "episodic memory" was coined by Endel Tulving in 1972, referring to the distinction between knowing and remembering: ''knowing'' is factual recollection (semantic) whereas ''remembering'' is a feeling that is located in the past (episodic). One of the main components of episodic memory is the process of recollection, which elicits the retrieval of contextual information pertaining to a specific event or experience that has occurred. Tulving seminally defined three key properties of episodi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorsal Tegmental Nucleus
The dorsal tegmental nucleus (DTN), also known as dorsal tegmental nucleus of Gudden, is a group of neurons located in the brainstem, which are involved in spatial navigation and orientation. Anatomy The dorsal tegmental nucleus is located in the brain stem near the midline. Two nuclei exist in both hemispheres. The DTN is generally subdivided into four parts called partes centralis, ventromedialis, anterior, and posterior. DTN contains a dense population of GABAergic cells. In the rat, few also express calbindin (CB) or calretinin (CR). Many of the DTN GABAergic cells do express parvalbumin (PV) with the densest expression in the pars ventralis portion. DTN neurons in rats contain small number of neuropeptide Y positive (NPY) neurons implicating a role in hunger and feeding. In rats, the DTN contains a small number of enkephalin, substance p, and glutamatergic neurons which project to mammillary. Circuitry As part of the Papez circuit The Papez circuit ,Livingston, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalamus
The thalamus (: thalami; from Greek language, Greek Wikt:θάλαμος, θάλαμος, "chamber") is a large mass of gray matter on the lateral wall of the third ventricle forming the wikt:dorsal, dorsal part of the diencephalon (a division of the forebrain). Nerve fibers project out of the thalamus to the cerebral cortex in all directions, known as the thalamocortical radiations, allowing hub (network science), hub-like exchanges of information. It has several functions, such as the relaying of sensory neuron, sensory and motor neuron, motor signals to the cerebral cortex and the regulation of consciousness, sleep, and alertness. Anatomically, the thalami are paramedian symmetrical structures (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 thalami ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hippocampus
The hippocampus (: hippocampi; via Latin from Ancient Greek, Greek , 'seahorse'), also hippocampus proper, is a major component of the brain of humans and many other vertebrates. In the human brain the hippocampus, the dentate gyrus, and the subiculum are components of the hippocampal formation located in the limbic system. The hippocampus plays important roles in the Memory consolidation, consolidation of information from short-term memory to long-term memory, and in spatial memory that enables Navigation#Navigation in spatial cognition, navigation. In humans, and other primates the hippocampus is located in the archicortex, one of the three regions of allocortex, in each cerebral hemisphere, hemisphere with direct neural projections to, and reciprocal indirect projections from the neocortex. The hippocampus, as the medial pallium, is a structure found in all vertebrates. In Alzheimer's disease (and other forms of dementia), the hippocampus is one of the first regions of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
