When the brain stem , trunk cerebri or truncus encephali ( latin truncus "trunk, trunk") of the below are diencephalon (diencephalon) localized areas of the brain , excluding the cerebellum (cerebellum), respectively.
The brain stem thus includes:
- Midbrain (mesencephalon)
- Bridge ( pons ) as part of the hind brain ( metencephalon )
- elongated medulla ( medulla oblongata ) or medullary brain ( myelencephalon )
The term brain stem is not synonymous with brain stem . The term brain stem stands for a term that includes not only the brain stem but also the diencephalon, and occasionally also the cerebellum and parts of the terminal brain (as basal ganglia ). However, it is not particularly useful from a developmental perspective or from a functional perspective to summarize the diencephalon with the midbrain, bridge and elongated medulla, and less so with the cerebellum and parts of the hindbrain.
The basic anatomical structures of the brain stem changed relatively little in the course of evolution compared to the phylogenetic development of the forebrain . The subdivision of the brainstem into mesencephalic, metencephalic and myelencephalic parts is most clearly recognizable on its ( ventral ) surface facing the front of the body , where the bridge is noticeable as a transverse bulge.
The brain stem controls the vital functions. For example breathing, blood pressure, reflexes etc.