from Greek: δίς ("dis") - twofold, double
The diencephalon is a part of the brain stem, which follows the mesencephalon on the cranial side. It encloses the 3rd ventricle (Ventriculus tertius cerebri).
Due to functional differences, the diencephalon can be divided into the following structures:
The diencephalon and the telencephalon belong to the secondary brain vesicles that develop from the prosencephalon.
The diencephalon contains centers for the olfactory, optical and auditive tract, the haptic perception and the emotional sensation.