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Postsubiculum
The subiculum (Latin for "support") also known as the subicular complex, or subicular cortex, is the most inferior component of the hippocampal formation. It lies between the entorhinal cortex and the CA1 hippocampal subfield. The subicular complex comprises a set of four related structures including the prosubiculum, presubiculum, postsubiculum and parasubiculum. Name The subiculum got its name from Karl Friedrich Burdach in his three-volume work ''Vom Bau und Leben des Gehirns'' (Vol. 2, §199). He originally named it subiculum cornu ammonis and so associated it with the rest of the hippocampal subfields. Structure The subicular complex receives input from CA1 and entorhinal cortical layer III pyramidal neurons and is the main output of the hippocampus proper. The pyramidal neurons send projections to the nucleus accumbens, septal nuclei, prefrontal cortex, lateral hypothalamus, nucleus reuniens, mammillary nuclei, entorhinal cortex and amygdala. The pyramidal neurons in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Head Direction Cells
Head direction (HD) cells are neurons found in a number of brain regions that increase their firing rates above baseline levels only when the animal's head points in a specific direction. They have been reported in rats, monkeys, mice, chinchillas and bats, but are thought to be common to all mammals, perhaps all vertebrates and perhaps even some invertebrates, and to underlie the "sense of direction". When the animal's head is facing in the cell's "preferred firing direction" these neurons fire at a steady rate (i.e., they do not show adaptation), but firing decreases back to baseline rates as the animal's head turns away from the preferred direction (usually about 45° away from this direction). HD cells are found in many brain areas, including the cortical regions of postsubiculum (also known as the dorsal presubiculum), retrosplenial cortex, and entorhinal cortex, and subcortical regions including the thalamus (the anterior dorsal and the lateral dorsal thalamic nuclei), latera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brodmann Area 27
Brodmann area 27 is a cytoarchitecturally defined cortical area that is a rostral part of the parahippocampal gyrus. It is commonly regarded as a synonym of presubiculum. The dorsal part of the presubiculum is more commonly known as the postsubiculum, and is of interest because it contains head direction cells, which are responsive to the facing direction of the head. See also * Brodmann area * List of regions in the human brain The human brain anatomical regions are ordered following standard neuroanatomy hierarchies. Functional, connective, and developmental regions are listed in parentheses where appropriate. Hindbrain (rhombencephalon) Myelencephalon * M ... References External links * For Neuroanatomy of this area visiBrainInfo 27 Medial surface of cerebral hemisphere {{neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cornu Ammonis Area 1
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 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 fibers of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleus Reuniens
The nucleus reuniens is a region of the thalamic midline nuclear group. In the human brain, it is located in the interthalamic adhesion (''massa intermedia''). It is also known as the medioventral nucleus. The nucleus reuniens receives afferent input from a large number of structures, mainly from limbic and limbic-associated structures. It sends projections to the medial prefrontal cortex, the hippocampus, perirhinal cortex, and entorhinal cortex The entorhinal cortex (EC) is an area of the brain's allocortex, located in the medial temporal lobe, whose functions include being a widespread network hub for memory, navigation, and the perception of time.Integrating time from experience in t ..., although there exist sparse connections to many other afferent structures as well. The unique medial prefrontal cortex and hippocampal connectivity allows reuniens to regulate neural traffic in this cortical network related to changes in an organism's attentiveness, making reuniens c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epilepsy
Epilepsy is a group of Non-communicable disease, non-communicable Neurological disorder, neurological disorders characterized by a tendency for recurrent, unprovoked Seizure, seizures. A seizure is a sudden burst of abnormal electrical activity in the brain that can cause a variety of symptoms, ranging from brief lapses of awareness or muscle jerks to prolonged convulsions. These episodes can result in physical injuries, either directly, such as broken bones, or through causing accidents. The diagnosis of epilepsy typically requires at least two unprovoked seizures occurring more than 24 hours apart. In some cases, however, it may be diagnosed after a single unprovoked seizure if clinical evidence suggests a high risk of recurrence. Isolated seizures that occur without recurrence risk or are provoked by identifiable causes are not considered indicative of epilepsy. The underlying cause is often unknown, but epilepsy can result from brain injury, stroke, infections, Brain tumor, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hippocampus Anatomy
Hippocampus anatomy describes the physical aspects and properties of the hippocampus, a neural structure in the medial temporal lobe of each cerebral hemisphere of the brain. It has a distinctive, curved shape that has been likened to the hippocampus (mythology), sea-horse creature of Greek mythology, and the Sheep, ram's horns of Amun#New Kingdom, Amun in Egyptian mythology. The general layout holds across the full range of mammals, although the details vary. For example, in the rat, the two hippocampi look similar to a pair of bananas, joined at the stems. In humans and other primates, the portion of the hippocampus near the base of the temporal lobe is much broader than the part at the top. Due to the three-dimensional curvature of the hippocampus, two-dimensional sections are commonly presented. Neuroimaging can show a number of different shapes, depending on the angle and location of the cut. Cerebral cortex, Cortical parts from the temporal lobe, parietal lobe, and th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posterior Cortex
Posterior cortex usually means the posterior (back) part of the complete cerebral cortex and includes the occipital, parietal, and temporal cortices. In other words, the posterior cortex includes all the cerebral cortex without the frontal cortex. In combination with specific cortical areas, 'posterior cortex' usually refers to the posterior (back) part of that cortical area. For example: the posterior parietal cortex is the posterior part of the parietal cortex and the posterior cingulate cortex is the posterior part of the cingulate cortex. Function of the posterior cortex The posterior cortex is the “sensory” cortex, much as the frontal cortex is the “action” cortex. The posterior cortex is responsible for encoding the sensory content (visual, auditory, and tactile) of any experience (both real and imaginary experience). The posterior cortex with the exception of the primary sensory areas ( Primary visual cortex (V1), primary auditory cortex, and somatosensory cort ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grid Cells
A grid cell is a type of neuron within the entorhinal cortex that fires at regular intervals as an animal navigates an open area, allowing it to understand its position in space by storing and integrating information about location, distance, and direction. Grid cells have been found in many animals, including rats, mice, bats, monkeys, and humans. Grid cells were discovered in 2005 by Edvard Moser, May-Britt Moser, and their students Torkel Hafting, Marianne Fyhn, and Sturla Molden at the Centre for the Biology of Memory (CBM) in Norway. They were awarded the 2014 Nobel Prize in Physiology or Medicine together with John O'Keefe for their discoveries of cells that constitute a positioning system in the brain. The arrangement of spatial firing fields, all at equal distances from their neighbors, led to a hypothesis that these cells encode a neural representation of Euclidean space. The discovery also suggested a mechanism for dynamic computation of self-position based on continu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasubiculum
In the rodent, the parasubiculum is a retrohippocampal isocortical structure, and a major component of the subicular complex. It receives numerous subcortical and cortical inputs, and sends major projections to the superficial layers of the entorhinal cortex (Amaral & Witter, 1995). The parasubicular area is a transitional zone between the presubiculum and the entorhinal area in the mouse (Paxinos-2001), the rat (Swanson, 1998) and the primate (Zilles, 1990). Defined on the basis of cytoarchitecture, it is more similar to the presubiculum than to the entorhinal area (Zilles, 1990), however electrophysiological evidence suggests a similarity with the entorhinal cortex (Funahashi and Stewart, 1997; Glasgow & Chapman, 2007). To be specific, cells in this area are modulated by local theta rhythm, and display theta-frequency membrane potential oscillations (Glasgow & Chapman, 2007; Taube, 1995). Furthermore, cells in the parasubiculum, and neighboring presubiculum, fire in relat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PLoS Biology
''PLOS Biology'' is a monthly peer-reviewed scientific journal covering all aspects of biology. Publication began on October 13, 2003. It is the first journal published by the Public Library of Science. The editor-in-chief is Nonia Pariente. In addition to research articles, the journal publishes magazine content aimed to be accessible to a broad audience. Article types in this section are essays, "unsolved mysteries", editorials, and synopses. Abstracting and indexing The journal is abstracted and indexed in: * Biological Abstracts * BIOSIS Previews *''Current Contents''/Agriculture, Biology & Environmental Sciences *''Current Contents''/Life Sciences *Chemical Abstracts Service * Embase *''Index Medicus''/MEDLINE/PubMed *Science Citation Index *Scopus *'' The Zoological Record'' According to ''Journal Citation Reports'', the journal had a 2023 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a type of journal ranking. Journals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bursting
Bursting, or burst firing, is an extremely diverse general phenomenon of the activation patterns of neurons in the central nervous system where periods of rapid action potential spiking are followed by quiescent periods much longer than typical inter-spike intervals. Bursting is thought to be important in the operation of robust central pattern generators, the transmission of neural codes, and some neuropathologies such as epilepsy. The study of bursting both directly and in how it takes part in other neural phenomena has been very popular since the beginnings of cellular neuroscience and is closely tied to the fields of neural synchronization, neural coding, plasticity, and attention. Observed bursts are named by the number of discrete action potentials they are composed of: a ''doublet'' is a two-spike burst, a ''triplet'' three and a ''quadruplet'' four. Neurons that are intrinsically prone to bursting behavior are referred to as ''bursters'' and this tendency to burst may ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
