In the rodent, the parasubiculum is a retrohippocampal isocortical structure, and a major component of the subicular complex. It receives numerous subcortical and cortical inputs, and sends major projections to the superficial layers of the entorhinal cortex (Amaral & Witter, 1995).

The parasubicular area is a transitional zone between the presubiculum and the entorhinal area in the mouse

Mouse

A mouse is a small mammal belonging to the order of rodents. The best known mouse species is the common house mouse . It is also a popular pet. In some places, certain kinds of field mice are also common. This rodent is eaten by large birds such as hawks and eagles...

 (Paxinos-2001), the rat

Rat

Rats are various medium-sized, long-tailed rodents of the superfamily Muroidea. "True rats" are members of the genus Rattus, the most important of which to humans are the black rat, Rattus rattus, and the brown rat, Rattus norvegicus...

 (Swanson, 1998) and the primate

Primate

A primate is a mammal of the order Primates , which contains prosimians and simians. Primates arose from ancestors that lived in the trees of tropical forests; many primate characteristics represent adaptations to life in this challenging three-dimensional environment...

 (Zilles, 1990). Defined on the basis of cytoarchitecture, it is more similar to the presubiculum than to the entorhinal area (Zilles, 1990), however electrophysiological evidence suggests a similarity with the entorhinal cortex (Funahashi and Stewart, 1997; Glasgow & Chapman, 2007). To be specific, cells in this area are modulated by local theta rhythm

Theta rhythm

A theta rhythm is an oscillatory pattern in EEG signals recorded either from inside the brain or from electrodes glued to the scalp. Two types of theta rhythm have been described...

, and display theta-frequency membrane potential oscillations (Glasgow & Chapman, 2007; Taube, 1995). Furthermore, cells in the parasubiculum, and neighboring presubiculum, fire in relation to the animal's location in space, suggesting properties similar to place cell

Place cell

Place cells are neurons in the hippocampus that exhibit a high rate of firing whenever an animal is in a specific location in an environment corresponding to the cell's "place field". These neurons are distinct from other neurons with spatial firing properties, such as grid cells, border cells,...

s. It is postulated that this area may play an integral role in spatial navigation and the integration of head-directional information (Chrobak & Buzsáki, 1994; Taube, 1995).

External links

• For Neuroanatomy of this area visit BrainInfo