Hippocampus

hippocampus-thumb.jpg

The hippocampus is a horseshoe shaped structure, with one hippocampus located on the right hempisphere of the brain and the other hippocampus on the left hemisphere. The volume of hippocampus is around 3 to 3.5 cm3 in adult humans.The hippocampus is the part of the brain inv olved in memory forming, organizing, and sto ring. As part of the limbic structure, the hippocampus is especially important for forming new memories and associating memories with emotions and sound. The hippocampus acts as a memory organizer by sending memories out to the appropriate part of the cerebral hemisphere for long-term storage and retrieving them when necessary.

Damage to the hippocampus does not affect some types of memory, such as the ability to learn new motor or cognitive skills. For example, playing a musical instrument or solving certain types of puzzels. This fact suggests that such abilities depend on different types of memory and different brain regions. Some researchers distinguish between conscious ''recollection'', which depends on the hippocampus, and ''familiarity'', which depends on portions of the medial temporal cortex. In case of Alzheimer's disease, the hippocampus is one of the brain parts that is primarily affected. This causes memory loss and disorientation. In general, damage to hippocampus can cause oxygen starvation, encephalitis, and medial temporal lobe epilepsy.

Navigation is another area, where hippocampus is involved. Hippocampus has 'place cells', that are responsible for this function. According to one theory, the hippocampus may act as a cognitive map, that helps in navigation. This is explains how people with weak hippocampus lack spatial memory and may forget about where they have been or where to go. This is why, it is said that a strong and intact hippocampus is required for spatial navigation tasks.

View Hippocampus and over 3,000,000 other topics on Qwiki.