hippocampus


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Related to hippocampus: amygdala, hypothalamus, limbic system

hippocampus

 [hip″o-kam´pus] (L.)
a curved elevation of gray matter on the floor of the inferior horn of the lateral ventricle; it is an important functional component of the limbic system.

hip·po·cam·pus

(hip'ō-kam'pŭs), [TA]
The complex, internally convoluted structure that forms the medial margin ("hem") of the cortical mantle of the cerebral hemisphere, bordering the choroid fissure of the lateral ventricle, and composed of two gyri (Ammon horn and the dentate gyrus), together with their white matter, the alveus and fimbria hippocampi. In monkeys, apes, and humans, the hippocampus is confined to the temporal lobe by the massive development of the corpus callosum. Cytoarchitecturally a unique form of allocortex (archicortex), the hippocampus forms part of the limbic system (formerly rhinencephalon). Its major afferent connections are with the entorhinal area of the parahippocampal gyrus and with the transparent septum; by way of the fornix, it projects to the septum, anterior nucleus of the thalamus, and mammillary body.
[G. hippocampos, seahorse]

hippocampus

/hip·po·cam·pus/ (hip″o-kam´pus) [L.] a curved elevation in the floor of the inferior horn of the lateral ventricle; a functional component of the limbic system, its efferent projections form the fornix.hippocam´pal

hippocampus

(hĭp′ə-kăm′pəs)
n. pl. hippocam·pi (-pī′)
1. A ridge in the floor of each lateral ventricle of the brain that consists mainly of gray matter and has a central role in memory processes.
2. Variant of hippocamp.

hip′po·cam′pal (-pəl) adj.

hippocampus

[hip′ōkam′pəs] pl. hippocampi
Etymology: Gk, hippokampos, seahorse
a curved convoluted elevation of the floor of the inferior horn of the lateral ventricle of the brain. It is composed of gray substance covered by a layer of white fibers, the alveus, and functions as an important component of the limbic system and of memory processing. Its efferent projections form the fornix of the cerebrum. Also called Ammon's horn, hippocampus major.

hippocampus

A limbic system structure located in the temporal lobe of the cerebral cortex.
 
Function
Processing short-term memory, encoding explicit memories for long-term storage, controlling autonomic functions, emotional expression, subjective experience, behavioural expression of affect.

Affected in
Anxiety, bipolarity, depression, panic, post-traumatic stress disorder.

hip·po·cam·pus

, pl. hippocampi (hip'ō-kam'pŭs, -pī) [TA]
The complex, internally convoluted structure that forms the medial margin of the cerebral hemisphere, bordering the choroid fissure of the lateral ventricle, and composed of two gyri (Ammon horn and the dentate gyrus), together with their white matter, the alveus, and fimbria hippocampi. In humans the hippocampus is confined to the temporal lobe by the massive development of the corpus callosum. The hippocampus forms part of the limbic system. Its major afferent connections are with the entorhinal area of the parahippocampal gyrus, and transparent septum; by way of the fornix it projects to the septum, anterior nucleus of the thalamus, and mammillary body.
[G. hippocampos, seahorse]

hippocampus

An infolded ridge of the surface of the brain (cerebral cortex) on either side. Each hippocampus forms a ridge on the floor of the LATERAL VENTRICLE. Disease or injury to the hippocampus causes memory defects. PET scanning in young subjects shows that the act of memorization is associated with a 5 per cent increase in blood flow to the hippocampus. From the Greek hippos , a horse, and kampos , a sea monster.

hippocampus

part of the limbic system of the central nervous system

hippocampus (hip·pō·kamˑ·ps),

n a part of the brain in the lateral ventricle that is important in learning and memory.

hip·po·cam·pus

, pl. hippocampi (hip'ō-kam'pŭs, -pī) [TA]
The complex, internally convoluted structure that forms the medial margin of the cerebral hemisphere, bordering the choroid fissure of the lateral ventricle, and composed of two gyri (Ammon's horn and the dentate gyrus), together with their white matter, the alveus, and fimbria hippocampi.
[G. hippocampos, seahorse]

hippocampus (hip´ōkam´pəs),

n a curved convoluted elevation of the floor of the inferior horn of the lateral ventricle of the brain. It is composed of gray substance covered by a layer of white fibers, or the alveus, and functions as an important component of the limbic system.

Hippocampus

see sea horse.

hippocampus

pl. hippocampi [L.] in evolutionary terms, an old part of the cerebral cortex that forms part of the floor of the lateral ventricle; identified by its white surface and convoluted appearance on section. It is examined for Negri bodies in suspected cases of rabies.

hippocampus major
hippocampus.
hippocampus minor
the lower of two medial elevations in the lateral cerebral ventricle.
References in periodicals archive ?
An inflammatory reaction might cause cells in the hippocampus to rev into an excited state and eventually die.
Abuse, depression, borderline personality disorder, and dissociative identity disorder also can decrease the volume of the hippocampus, according to a review of the literature.
Niemi WD, Audi J, Bush B, Carpenter DO, PCBs reduce long-term potentiation in the CA1 region of rat hippocampus.
They were also able to show that turning off other cells in the hippocampus did not affect retrieval of that memory, and to follow fibers from the hippocampus to specific cells in the cortex.
This association of two sensory inputs involves the cerebellum which coordinates the necessary movements, as well as the hippocampus and the cerebral cortex, which are important learning and memory centres.
For this study, the researchers modified a set of neurons in the basolateral amygdala (BLA); these neurons send long projections to cells of the ventral hippocampus.
Kaoru Inokuchi of the University of Toyama in Japan and his colleagues show something different: Newborn neurons weaken or disrupt connections encoding old memories in the hippocampus.
Fifteen or more studies have shown a reduction in volume of the hippocampus in patients with chronic PTSD," Dr.
In the first study, Chen's team learned that stem cells existed everywhere in the brain by testing tissue from different parts of adult mice brains in cultures containing support cells (known as astrocytes) from the hippocampus, where stem cells do regenerate.
Marijuana changes the brain's hippocampus, the seat of short-term-- []
Further investigation showed that a specific component of the local environment, the regional astrocytes from the hippocampus were capable of instructing these stem cells to adopt a neuronal fate in vitro.
It is usually caused by damage to the hippocampus, the seahorse-shaped region of the brain, located at the front of the temporal lobes, reponsible for recording memories.