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Information about Entorhinal Cortex

Brain: Entorhinal cortex
Medial surface. (Entorhinal cortex approximately maps to areas 28 and 34, at lower left.)
Part ofTemporal lobe
ArteryPosterior cerebral
Choroid
VeinInferior striate
NeuroNameshier-150
MeSH Entorhinal+Cortex
The entorhinal cortex (EC) is an important memory center in the brain. The EC forms the main input to the hippocampus and is responsible for the pre-processing (familiarity) of the input signals. In the reflex nictitating membrane response of classical trace conditioning, the association of impulses from the eye and the ear occurs in the entorhinal cortex. The EC-hippocampus system plays an important role in memory consolidation and memory optimization in sleep.

Entorhinal cortex is one of the first areas to be affected in Alzheimer's Disease, and one of the first symptoms is impaired sense of direction. In 2005, it was discovered that entorhinal cortex contains a neural map of the spatial environment.[1]

The entorhinal cortex show a modular organization, with different properties and connections in different areas. Neurons in the lateral entorhinal cortex exhibit little spatial selectivity[2], whereas neurons of the medial entorhinal (MEA) cortex exhibit multiple "place fields" that are arranged in an hexagonal pattern, and are therefore called "grid cells." These fields and spacing between fields increase from the dorso-lateral MEA to the ventro-medial MEA.[3][1]

Anatomy

In rodents, EC is located at the caudal end of the temporal lobe and is usually divided into medial and lateral regions (with three bands with distinct properties and connectivity running perpendicular across the whole area). A distinguishing characteristic of EC is the lack of cell bodies where layer IV should be; this layer is called the lamina dissecans.

Inputs and outputs

The superficial layers - layers II and III - of EC project to the dentate gyrus and hippocampus: Layer II projects primarily to dentate gyrus and hippocampal region CA3; layer III projects primarily to hippocampal region CA1 and the subiculum. These layers receive input from other cortical areas, especially associational, perirhinal, and parahippocampal cortices, as well as prefrontal cortex. EC as a whole, therefore, receives highly-processed input from every sensory modality, as well as input relating to ongoing cognitive processes, though it should be stressed that, within EC, this information remains at least partially segregated.

The deep layers, especially layer V, receive one of the three main outputs of the hippocampus and, in turn, reciprocate connections from other cortical areas that project to superficial EC.

Brodmann's areas

References

1. ^ Hafting T, Fyhn M, Molden S, Moser M, Moser E (2005). "Microstructure of a spatial map in the entorhinal cortex". Nature 436 (7052): 801-6. PMID 15965463. 
2. ^ Hargreaves E, Rao G, Lee I, Knierim J (2005). "Major dissociation between medial and lateral entorhinal input to dorsal hippocampus". Science 308 (5729): 1792-4. PMID 15961670. 
3. ^ Fyhn M, Molden S, Witter M, Moser E, Moser M (2004). "Spatial representation in the entorhinal cortex". Science 305 (5688): 1258-64. PMID 15333832. 
4. ^

External links

The temporal lobes are part of the cerebrum. They lie at the sides of the brain, beneath the lateral or Sylvian fissure. Seen in profile, the human brain looks something like a boxing glove. The temporal lobes are where the thumbs would be.
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In human anatomy, the posterior cerebral artery is the blood vessel that supplies oxygenated blood to the posterior aspect of the brain (occipital lobe). It arises from the basilar artery and connects with the ipsilateral middle cerebral artery and internal carotid artery via the
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The anterior choroidal artery originates from the internal carotid artery, though it will rarely arise from the middle cerebral artery.

Structures supplied

The anterior choroidal artery serves many structures in the cerebrum:

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The basal vein is formed at the anterior perforated substance by the union of
  • (a) a small anterior cerebral vein which accompanies the anterior cerebral artery,
  • (b) the deep middle cerebral vein (deep Sylvian vein

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NeuroNames is a system of nomenclature for the human and/or macaque brain.

It is maintained by the University of Washington and is a part of a tool called "BrainInfo". BrainInfo helps one identify structures in the brain.
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Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. Created and updated by the United States National Library of Medicine (NLM), it is used by the MEDLINE/PubMed
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In psychology, memory is an organism's ability to store, retain, and subsequently retrieve information. Traditional studies of memory began in the realms of philosophy, including techniques of artificially enhancing the memory.
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In animals, the brain or encephalon (Greek for "in the skull"), is the control center of the central nervous system, responsible for behavior. The brain is located in the head, protected by the skull and close to the primary sensory apparatus of vision, hearing,
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The hippocampus is a part of the forebrain, located in the medial temporal lobe. It forms a part of the limbic system and plays a part in memory and spatial navigation. Humans and other mammals have two hippocampi, one in each side of the brain.
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The Nictitating membrane is a transparent or translucent third eyelid present in some animals that can be drawn across the eye for protection and to moisten the eye while also keeping visibility.
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Eyes are organs of vision that detect light. Different kinds of light-sensitive organs are found in a variety of organisms. The simplest eyes do nothing but detect whether the surroundings are light or dark, while more complex eyes can distinguish shapes and colors.
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outer ear is the most external portion of the ear. The outer ear includes the pinnae (also called auricle), the ear canal, and the very most superficial layer of the ear drum (also called the tympanic membrane).
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The Entorhinal Cortex (EC) is a major part of the hippocampal formation of the human brain, and is reciprocally connected with the hippocampus.

The hippocampal formation, which consists of the hippocampus, perirhinal cortex, the dentate gyrus, the subicular areas and
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The broad definition of memory consolidation is the process by which recent memories are crystallised into long-term memory. The word "consolidation" is used to refer to different levels:
  1. Molecular consolidation

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In computing, optimization is the process of modifying a system to make some aspect of it work more efficiently or use fewer resources. For instance, a computer program may be optimized so that it executes more rapidly, or is capable of operating within a reduced amount of memory
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Sleep is the state of natural rest observed throughout the animal kingdom, in all mammals and birds, and in many reptiles, amphibians, and fish.

In humans, other mammals, and many other animals that have been studied — such as fish, birds, ants, and fruit-flies —
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grid cell is a type of neuron found in the entorhinal cortex (EC) that fires strongly when an animal is in specific locations in an environment. Grid cells were discovered in 2005 and it is hypothesized that a network of these cells constitute a mental map of the spatial
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In sciences dealing with the anatomy of animals, precise anatomical terms of location are necessary for a variety of reasons. Non-scientists often wonder why zoological and human anatomists use complex terminology to describe locations on a body, when common terms like "up",
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The temporal lobes are part of the cerebrum. They lie at the sides of the brain, beneath the lateral or Sylvian fissure. Seen in profile, the human brain looks something like a boxing glove. The temporal lobes are where the thumbs would be.
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medial magma (or medial groupoid) is a set with a binary operation which satisfies the identity

, or more simply,


using the convention that juxtaposition has higher precedence.
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The dentate gyrus is part of the hippocampal formation. It contains granule cells, which project to the pyramidal cells, but mostly to the interneurons of the CA3 subfield of the hippocampus. The granule cells are the principal excitatory neurons of the dentate gyrus.
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The hippocampus is a part of the forebrain, located in the medial temporal lobe. It forms a part of the limbic system and plays a part in memory and spatial navigation. Humans and other mammals have two hippocampi, one in each side of the brain.
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The dentate gyrus is part of the hippocampal formation. It contains granule cells, which project to the pyramidal cells, but mostly to the interneurons of the CA3 subfield of the hippocampus. The granule cells are the principal excitatory neurons of the dentate gyrus.
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The subiculum (Latin for "support") is the most inferior component of the hippocampal formation. It lies between the entorhinal cortex and the CA1 subfield of the hippocampus proper.
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prefrontal cortex is the anterior part of the frontal lobes of the brain, lying in front of the motor and premotor areas. Cytoarchitectonically, it is defined by the presence of an internal granular layer IV (in contrast to the agranular premotor cortex).
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The hippocampus is a part of the forebrain, located in the medial temporal lobe. It forms a part of the limbic system and plays a part in memory and spatial navigation. Humans and other mammals have two hippocampi, one in each side of the brain.
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Guenon

Brodmann area 28 is a subdivision of the cerebral cortex of the guenon defined on the basis of cytoarchitecture. Brodmann regarded its location adjacent to the hippocampus as imprecisely represented in the illustration of the cortex of the guenon brain in
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This area is known as dorsal entorhinal area 34. It is a subdivision of the cytoarchitecturally defined hippocampal region of the human cerebral cortex. It is located in the entorhinal area on the medial aspect of the temporal lobe.
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BrainMaps is an NIH-funded interactive zoomable high-resolution digital brain atlas and virtual microscope that is based on more than 20 million megapixels (50 terabytes) of scanned images of serial sections of both primate and non-primate brains and that is integrated with a
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