Entorhinal cortex

From Psy3241

Current revision as of 17:36, 27 April 2008

The entorhinal cortex: a subregion of the parahippocampal gyrus of the temporal lobe.

The entorhinal cortex (EC) is located in the inferior medial temporal lobe and is adjacent to the hippocampus. Because the hippocampus does not receive neocortical input directly, the function of the EC is to transmit and relay information to and from the hippocampus.

Through the EC, the hippocampus can maintain connections with the temporal, frontal, parietal lobes and their surrounding structures (which include the parahippocampal gyrus, and allocortical tissues, the perirhinal cortex, septal nuclei and amygdale) through the EC.

As an integral part of the hippocampal system, the EC plays a major role in memory and cognitive processing. The EC contains between seven and eight layers: the superficial layers project to the dentate gyrus and hippocampus and receive input mainly from the prefrontal cortex and other cortical areas, such as the perirhinal, and parahippocampal cortices; the deeper layers receive outputs of the hippocampus and reciprocate connections from other cortical areas that project to superficial layers of the EC.

The specific function of the EC in regards to memory is unknown because it is extremely difficult to isolate it from the hippocampus without severely damaging both areas of the brain. It is known, however, that damage to the EC is associated with Alzheimer’s Disease and impaired sense of direction, which is supported by the notion that the EC contains a map of the spatial environment. The EC, as well as the rest of the hippocampal system, is also indicated in memory consolidation and optimization during sleep.

See also: Brodmann area 28, and Brodmann area 34.

References:

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