Midbrain

The midbrain or the mesencephalon goes from the pons to the diencephalon. The cerebral aqueduct passes through the midbrain, if you remember; this connects the third and fourth ventricle together. The midbrain also contains tracts of gray and white matter, just like the medulla oblongata. The midbrain contains a number of nuclei, including the substantia nigra; these nuclei control subconscious muscle movements.