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

(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

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.

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]
References in periodicals archive ?
The researchers mapped out which cells in the hippocampus were being activated when male mice made new memories of positive, neutral, and negative experiences.
Their studies reveal just how different the roles of the top and bottom parts of the hippocampus are.
'These findings suggest that the 'place' part of the hippocampus is not just involved in navigating the physical landscape," concludes Ulanovsky "It plays an important role in navigating the social landscape as well."
In the first part of our study, we observed that the excitability of the hippocampus in the SA group was significantly elevated 1.5 h after SA injection, as compared with the saline group.
"Based on the representative images they present, the cells they call new neurons in the adult hippocampus are very different in shape and appearance from what would be considered a young neuron in other species, or what we have observed in humans in young children," they said in an email to AFP.
the changes of AMPA receptors subunits GluA1-3 in the hippocampus following chronic stress.
We therefore predicted that older adults who trained on platform games such as Super Mario 64 would display increased grey matter in the hippocampus," say the researchers.
The more depleted the hippocampus becomes, the more a person is at risk of developing brain illnesses ranging from depression to Post Traumatic Stress Disorder (PTSD) and Alzheimer's disease, said the researchers.
The associated memory cells that fired at the time - in three different parts of the brain, the hippocampus, the prefrontal cortex and the basolateral amygdala, which stores emotional associations of memories -  were labeled.
zosterae (con alrededor de 3,8 cm de alto maximo), se encuentra unicamente en el Golfo de Mexico y de Bahamas a Bermuda (Masonjones & Lewis, 2000; Lourie et al, 2004; Rose et al, 2014), mientras que el recientemente descrito Hippocampus patagonicus (Piacentino & Luzzatto, 2004) (con tamano maximo de 10,3 cm) tiene la distribucion mas austral y restringida a la costa atlantica argentina (Piacentino & Luzzatto, 2004; Luzzatto et al, 2012; Gonzalez et al, 2014).
Brain free-floating sections (20 [micro]m thick) encompassing the hippocampus were prepared using a freezing microtome (Microm, Germany).
However, accurate and reliable automatic segmentation of medial temporal lobe structures, such as the hippocampus, is still a challenging.