It is a part of hippocampus and sometimes it also another name for hippocampus. It is named after a Egyptian deity(God) Amun. It is also known as Ram’s horn. Belongs to Limbic system of brain. It form longitudinal elevation in the floor of inferior horn of lateral ventricle.
It is part of cerebral cortex. In primitive animals it part of medial temporal gyrus.
Input(Afferents): From area 28(entorhinal area)
- Fornix(Main efferent tract)
- Commissure of fornix / Hippocampal commissure to opposite side hippocampus.
- Septal and anterior hypothalamic regions.
- To mammillary body.
- It plays important role in recent memory.
- It also helps in formation of short term memory to long term memory.
- It acts as a integrative centre by influencing endocrine and visceral functions and also emotional states. This due to its connections with anterior hypothalamus, septal nuclei and cingulate gyrus(through mammillary body).
Lesion/Damage: Damage to ammon’s horn results in:
- Loss of formation of new memories
- Retrograde amnesia
- Severe depression.