The hippocampus is a major component of the brains of humans and other mammals. It belongs to the limbic system and plays important roles in long term memory and spatial navigation. Like the cerebral cortex, with which it is closely associated, it is a paired structure, with mirror-image halves in the left and right sides of the brain. In humans and other primates, the hippocampus is located inside the medial temporal lobe, beneath the cortical surface. In rodents, the hippocampus has been studied extensively as part of the brain system responsible for spatial memory and navigation. Many neurons in the rat and mouse hippocampus respond as place cells: that is, they fire bursts of action potentials when the animal passes through a specific part of its environment. Because of its densely packed layers of neurons, the hippocampus has frequently been used as a model system for studying neurophysiology. The form of neural plasticity known as long term potentiation (LTP) was first discovered to occur in the hippocampus and has often been studied in this structure. LTP is widely believed to be one of the main neural mechanisms by which memory is stored in the brain.

Read the rest of this article: http://en.wikipedia.org/wiki/Hippocampus

_______________________________ Today's selected anniversaries:

1809:

Peninsular War: French forces under Joseph Bonaparte suffered 7,270 casualties while Sir Arthur Wellesley's Anglo-Spanish army had 6,700 at an inconclusive battle in Talavera, Spain. http://en.wikipedia.org/wiki/Battle_of_Talavera

1942:

World War II: Intending to increase Soviet morale and patriotism, Joseph Stalin issued Order No. 227, ordering troops "Not a step back!" (not to retreat) without an order or be subject to a military tribunal. http://en.wikipedia.org/wiki/Order_No._227

1976:

An earthquake measuring at least 8.2 on the Richter magnitude scale, one of the deadliest in history, flattened Tangshan, China, killing at least 240,000 people. http://en.wikipedia.org/wiki/1976_Tangshan_earthquake

1990:

Alberto Fujimori took office as President of Peru, becoming the first person of Japanese descent to be the head of government of a Latin American nation. http://en.wikipedia.org/wiki/Alberto_Fujimori

2005:

The Provisional Irish Republican Army announced an end to its armed campaign to overthrow British rule in Northern Ireland to create a United Ireland. http://en.wikipedia.org/wiki/Provisional_Irish_Republican_Army

_____________________________ Wiktionary's word of the day:

nostrify (v): 1. To nostrificate; to grant recognition to a degree from a foreign university. 2. To adopt, accept, or include as part of one's own culture http://en.wiktionary.org/wiki/nostrify

___________________________ Wikiquote quote of the day:

If I could only give three words of advice, they would be, "Tell the Truth." If I got three more words, I'd add, "All the time." --Randy Pausch http://en.wikiquote.org/wiki/Randy_Pausch