Corpus: Mammillary body

The corpus mamillare is a paired elevation on the underside of the brain between the crura cerebri. It is located at the front end of the fornix and is part of the limbic system and thus of the diencephalon.

The corpus mamillare is described as a marrow-rich part of the hypothalamus, but has no connections to the other, marrow-poor regions of the hypothalamus. Via its connections to the fornix and the fasciculus mamillothalamicus, it is involved in the Papez circle.

In the Papez circuit, the first functional concept of the limbic system, the corpus mamillare was still a central element. Today, it is assumed that the amygdala is the relevant core area for emotions. The corpus mamillare, on the other hand, is thought to be significantly involved in memory processes.

The mamillothalamic tract, which runs to the anterior thalamic nuclei, and the mamillotegmental tract, which sends its fibres to the mesencephalic tegmentum, originate in the lateral and medial nucleus mamillaris. Fibres from the subiculum reach the corpus mamillare through the fornix. Some neurones of the corpus mamillare are histaminergic.

Blood supply[Bearbeiten]

The corpora mamillaria are supplied by perforating vascular branches that originate from the P1 segment of the posterior cerebral artery (PCA), mostly from the posteromedial central arteries. Branches of the posterior communicating artery (PCom) can also be considered as a source of supply.

Alcoholism can lead to toxic lesions and thus to degeneration of the corpus mamillare and the medial thalamus, which is clinically referred to as Wernicke-Korsakow syndrome. Vascular and glial proliferations cause haemorrhages and tissue loosening. Brain incisions with corresponding haemorrhages in the corpora mamillaria are therefore also pejoratively referred to as boozer incisions. Memory disorders and confabulation occur.